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Added in API level 1

public abstract class

ViewGroup

extends View
implements ViewManager ViewParent

java.lang.Object
↳	android.view.View
	↳	android.view.ViewGroup

Known Direct Subclasses

AbsoluteLayout, AdapterView<T extends Adapter>, DrawerLayout, FragmentBreadCrumbs, FrameLayout, GridLayout, LinearLayout, PagerTitleStrip, RelativeLayout, SlidingDrawer, SlidingPaneLayout, ViewPager

AbsoluteLayout	This class was deprecated in API level 3. Use `FrameLayout`, `RelativeLayout` or a custom layout instead.
AdapterView<T extends Adapter>	An AdapterView is a view whose children are determined by an `Adapter`.
DrawerLayout	DrawerLayout acts as a top-level container for window content that allows for interactive "drawer" views to be pulled out from the edge of the window.
FragmentBreadCrumbs	Helper class for showing "bread crumbs" representing the fragment stack in an activity.
FrameLayout	FrameLayout is designed to block out an area on the screen to display a single item.
GridLayout	A layout that places its children in a rectangular grid.
LinearLayout	A Layout that arranges its children in a single column or a single row.
PagerTitleStrip	PagerTitleStrip is a non-interactive indicator of the current, next, and previous pages of a `ViewPager`.
RelativeLayout	A Layout where the positions of the children can be described in relation to each other or to the parent.
SlidingDrawer	This class was deprecated in API level 17. This class is not supported anymore. It is recommended you base your own implementation on the source code for the Android Open Source Project if you must use it in your application.
SlidingPaneLayout	SlidingPaneLayout provides a horizontal, multi-pane layout for use at the top level of a UI.
ViewPager	Layout manager that allows the user to flip left and right through pages of data.

Known Indirect Subclasses

AbsListView, AbsSpinner, AdapterViewAnimator, AdapterViewFlipper, AppWidgetHostView, CalendarView, DatePicker, DialerFilter, ExpandableListView, and 21 others.

AbsListView	Base class that can be used to implement virtualized lists of items.
AbsSpinner	An abstract base class for spinner widgets.
AdapterViewAnimator	Base class for a `AdapterView` that will perform animations when switching between its views.
AdapterViewFlipper	Simple `ViewAnimator` that will animate between two or more views that have been added to it.
AppWidgetHostView	Provides the glue to show AppWidget views.
CalendarView	This class is a calendar widget for displaying and selecting dates.
DatePicker	This class is a widget for selecting a date.
DialerFilter
ExpandableListView	A view that shows items in a vertically scrolling two-level list.
FragmentTabHost	Special TabHost that allows the use of `Fragment` objects for its tab content.
Gallery	This class was deprecated in API level 16. This widget is no longer supported. Other horizontally scrolling widgets include `HorizontalScrollView` and `ViewPager` from the support library.
GestureOverlayView	A transparent overlay for gesture input that can be placed on top of other widgets or contain other widgets.
GridView	A view that shows items in two-dimensional scrolling grid.
HorizontalScrollView	Layout container for a view hierarchy that can be scrolled by the user, allowing it to be larger than the physical display.
ImageSwitcher
ListView	A view that shows items in a vertically scrolling list.
MediaController	A view containing controls for a MediaPlayer.
NumberPicker	A widget that enables the user to select a number form a predefined range.
PagerTabStrip	PagerTabStrip is an interactive indicator of the current, next, and previous pages of a `ViewPager`.
RadioGroup	This class is used to create a multiple-exclusion scope for a set of radio buttons.
ScrollView	Layout container for a view hierarchy that can be scrolled by the user, allowing it to be larger than the physical display.
SearchView	A widget that provides a user interface for the user to enter a search query and submit a request to a search provider.
Spinner	A view that displays one child at a time and lets the user pick among them.
StackView
TabHost	Container for a tabbed window view.
TabWidget	Displays a list of tab labels representing each page in the parent's tab collection.
TableLayout	A layout that arranges its children into rows and columns.
TableRow	A layout that arranges its children horizontally.
TextSwitcher	Specialized `ViewSwitcher` that contains only children of type `TextView`.
TimePicker	A view for selecting the time of day, in either 24 hour or AM/PM mode.
TwoLineListItem	This class was deprecated in API level 17. This class can be implemented easily by apps using a `RelativeLayout` or a `LinearLayout`.
ViewAnimator	Base class for a `FrameLayout` container that will perform animations when switching between its views.
ViewFlipper	Simple `ViewAnimator` that will animate between two or more views that have been added to it.
ViewSwitcher	`ViewAnimator` that switches between two views, and has a factory from which these views are created.
WebView	A View that displays web pages.
ZoomControls	The `ZoomControls` class displays a simple set of controls used for zooming and provides callbacks to register for events.

Class Overview

A ViewGroup is a special view that can contain other views (called children.) The view group is the base class for layouts and views containers. This class also defines the ViewGroup.LayoutParams class which serves as the base class for layouts parameters.

Also see ViewGroup.LayoutParams for layout attributes.

Developer Guides

For more information about creating user interface layouts, read the XML Layouts developer guide.

Here is a complete implementation of a custom ViewGroup that implements a simple FrameLayout along with the ability to stack children in left and right gutters.

import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.RemoteViews;

/**
 * Example of writing a custom layout manager.  This is a fairly full-featured
 * layout manager that is relatively general, handling all layout cases.  You
 * can simplify it for more specific cases.
 */
@RemoteViews.RemoteView
public class CustomLayout extends ViewGroup {
    /** The amount of space used by children in the left gutter. */
    private int mLeftWidth;

    /** The amount of space used by children in the right gutter. */
    private int mRightWidth;

    /** These are used for computing child frames based on their gravity. */
    private final Rect mTmpContainerRect = new Rect();
    private final Rect mTmpChildRect = new Rect();

    public CustomLayout(Context context) {
        super(context);
    }

    public CustomLayout(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public CustomLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    /**
     * Any layout manager that doesn't scroll will want this.
     */
    @Override
    public boolean shouldDelayChildPressedState() {
        return false;
    }

    /**
     * Ask all children to measure themselves and compute the measurement of this
     * layout based on the children.
     */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int count = getChildCount();

        // These keep track of the space we are using on the left and right for
        // views positioned there; we need member variables so we can also use
        // these for layout later.
        mLeftWidth = 0;
        mRightWidth = 0;

        // Measurement will ultimately be computing these values.
        int maxHeight = 0;
        int maxWidth = 0;
        int childState = 0;

        // Iterate through all children, measuring them and computing our dimensions
        // from their size.
        for (int i = 0; i < count; i++) {
            final View child = getChildAt(i);
            if (child.getVisibility() != GONE) {
                // Measure the child.
                measureChildWithMargins(child, widthMeasureSpec, 0, heightMeasureSpec, 0);

                // Update our size information based on the layout params.  Children
                // that asked to be positioned on the left or right go in those gutters.
                final LayoutParams lp = (LayoutParams) child.getLayoutParams();
                if (lp.position == LayoutParams.POSITION_LEFT) {
                    mLeftWidth += Math.max(maxWidth,
                            child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin);
                } else if (lp.position == LayoutParams.POSITION_RIGHT) {
                    mRightWidth += Math.max(maxWidth,
                            child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin);
                } else {
                    maxWidth = Math.max(maxWidth,
                            child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin);
                }
                maxHeight = Math.max(maxHeight,
                        child.getMeasuredHeight() + lp.topMargin + lp.bottomMargin);
                childState = combineMeasuredStates(childState, child.getMeasuredState());
            }
        }

        // Total width is the maximum width of all inner children plus the gutters.
        maxWidth += mLeftWidth + mRightWidth;

        // Check against our minimum height and width
        maxHeight = Math.max(maxHeight, getSuggestedMinimumHeight());
        maxWidth = Math.max(maxWidth, getSuggestedMinimumWidth());

        // Report our final dimensions.
        setMeasuredDimension(resolveSizeAndState(maxWidth, widthMeasureSpec, childState),
                resolveSizeAndState(maxHeight, heightMeasureSpec,
                        childState << MEASURED_HEIGHT_STATE_SHIFT));
    }

    /**
     * Position all children within this layout.
     */
    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        final int count = getChildCount();

        // These are the far left and right edges in which we are performing layout.
        int leftPos = getPaddingLeft();
        int rightPos = right - left - getPaddingRight();

        // This is the middle region inside of the gutter.
        final int middleLeft = leftPos + mLeftWidth;
        final int middleRight = rightPos - mRightWidth;

        // These are the top and bottom edges in which we are performing layout.
        final int parentTop = getPaddingTop();
        final int parentBottom = bottom - top - getPaddingBottom();

        for (int i = 0; i < count; i++) {
            final View child = getChildAt(i);
            if (child.getVisibility() != GONE) {
                final LayoutParams lp = (LayoutParams) child.getLayoutParams();

                final int width = child.getMeasuredWidth();
                final int height = child.getMeasuredHeight();

                // Compute the frame in which we are placing this child.
                if (lp.position == LayoutParams.POSITION_LEFT) {
                    mTmpContainerRect.left = leftPos + lp.leftMargin;
                    mTmpContainerRect.right = leftPos + width + lp.rightMargin;
                    leftPos = mTmpContainerRect.right;
                } else if (lp.position == LayoutParams.POSITION_RIGHT) {
                    mTmpContainerRect.right = rightPos - lp.rightMargin;
                    mTmpContainerRect.left = rightPos - width - lp.leftMargin;
                    rightPos = mTmpContainerRect.left;
                } else {
                    mTmpContainerRect.left = middleLeft + lp.leftMargin;
                    mTmpContainerRect.right = middleRight - lp.rightMargin;
                }
                mTmpContainerRect.top = parentTop + lp.topMargin;
                mTmpContainerRect.bottom = parentBottom - lp.bottomMargin;

                // Use the child's gravity and size to determine its final
                // frame within its container.
                Gravity.apply(lp.gravity, width, height, mTmpContainerRect, mTmpChildRect);

                // Place the child.
                child.layout(mTmpChildRect.left, mTmpChildRect.top,
                        mTmpChildRect.right, mTmpChildRect.bottom);
            }
        }
    }

    // ----------------------------------------------------------------------
    // The rest of the implementation is for custom per-child layout parameters.
    // If you do not need these (for example you are writing a layout manager
    // that does fixed positioning of its children), you can drop all of this.

    @Override
    public LayoutParams generateLayoutParams(AttributeSet attrs) {
        return new CustomLayout.LayoutParams(getContext(), attrs);
    }

    @Override
    protected LayoutParams generateDefaultLayoutParams() {
        return new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
    }

    @Override
    protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) {
        return new LayoutParams(p);
    }

    @Override
    protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
        return p instanceof LayoutParams;
    }

    /**
     * Custom per-child layout information.
     */
    public static class LayoutParams extends MarginLayoutParams {
        /**
         * The gravity to apply with the View to which these layout parameters
         * are associated.
         */
        public int gravity = Gravity.TOP | Gravity.START;

        public static int POSITION_MIDDLE = 0;
        public static int POSITION_LEFT = 1;
        public static int POSITION_RIGHT = 2;

        public int position = POSITION_MIDDLE;

        public LayoutParams(Context c, AttributeSet attrs) {
            super(c, attrs);

            // Pull the layout param values from the layout XML during
            // inflation.  This is not needed if you don't care about
            // changing the layout behavior in XML.
            TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.CustomLayoutLP);
            gravity = a.getInt(R.styleable.CustomLayoutLP_android_layout_gravity, gravity);
            position = a.getInt(R.styleable.CustomLayoutLP_layout_position, position);
            a.recycle();
        }

        public LayoutParams(int width, int height) {
            super(width, height);
        }

        public LayoutParams(ViewGroup.LayoutParams source) {
            super(source);
        }
    }
}

If you are implementing XML layout attributes as shown in the example, this is the corresponding definition for them that would go in res/values/attrs.xml:

<declare-styleable name="CustomLayoutLP">
    <attr name="android:layout_gravity" />
    <attr name="layout_position">
        <enum name="middle" value="0" />
        <enum name="left" value="1" />
        <enum name="right" value="2" />
    </attr>
</declare-styleable>

Finally the layout manager can be used in an XML layout like so:

<com.example.android.apis.view.CustomLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res/com.example.android.apis"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    <!-- put first view to left. -->
    <TextView
            android:background="@drawable/filled_box"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            app:layout_position="left"
            android:layout_gravity="fill_vertical|center_horizontal"
            android:text="l1"/>

    <!-- stack second view to left. -->
    <TextView
            android:background="@drawable/filled_box"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            app:layout_position="left"
            android:layout_gravity="fill_vertical|center_horizontal"
            android:text="l2"/>

    <!-- also put a view on the right. -->
    <TextView
            android:background="@drawable/filled_box"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            app:layout_position="right"
            android:layout_gravity="fill_vertical|center_horizontal"
            android:text="r1"/>

    <!-- by default views go in the middle; use fill vertical gravity -->
    <TextView
            android:background="@drawable/green"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="fill_vertical|center_horizontal"
            android:text="fill-vert"/>

    <!-- by default views go in the middle; use fill horizontal gravity -->
    <TextView
            android:background="@drawable/green"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical|fill_horizontal"
            android:text="fill-horiz"/>

    <!-- by default views go in the middle; use top-left gravity -->
    <TextView
            android:background="@drawable/blue"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="top|left"
            android:text="top-left"/>

    <!-- by default views go in the middle; use center gravity -->
    <TextView
            android:background="@drawable/blue"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:text="center"/>

    <!-- by default views go in the middle; use bottom-right -->
    <TextView
            android:background="@drawable/blue"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|right"
            android:text="bottom-right"/>

</com.example.android.apis.view.CustomLayout>

Summary

Nested Classes
class	ViewGroup.LayoutParams	LayoutParams are used by views to tell their parents how they want to be laid out.
class	ViewGroup.MarginLayoutParams	Per-child layout information for layouts that support margins.
interface	ViewGroup.OnHierarchyChangeListener	Interface definition for a callback to be invoked when the hierarchy within this view changed.

XML Attributes
Attribute Name	Related Method	Description
android:addStatesFromChildren		Sets whether this ViewGroup's drawable states also include its children's drawable states.
android:alwaysDrawnWithCache		Defines whether the ViewGroup should always draw its children using their drawing cache or not.
android:animateLayoutChanges	setLayoutTransition(LayoutTransition)	Defines whether changes in layout (caused by adding and removing items) should cause a LayoutTransition to run.
android:animationCache		Defines whether layout animations should create a drawing cache for their children.
android:clipChildren	setClipChildren(boolean)	Defines whether a child is limited to draw inside of its bounds or not.
android:clipToPadding	setClipToPadding(boolean)	Defines whether the ViewGroup will clip its drawing surface so as to exclude the padding area.
android:descendantFocusability		Defines the relationship between the ViewGroup and its descendants when looking for a View to take focus.
android:layoutAnimation		Defines the layout animation to use the first time the ViewGroup is laid out.
android:layoutMode	setLayoutMode(int)	Defines the layout mode of this ViewGroup.
android:persistentDrawingCache		Defines the persistence of the drawing cache.
android:splitMotionEvents	setMotionEventSplittingEnabled(boolean)	Sets whether this ViewGroup should split MotionEvents to separate child views during touch event dispatch.

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Inherited XML Attributes

From class android.view.View

Constants
int	CLIP_TO_PADDING_MASK	We clip to padding when FLAG_CLIP_TO_PADDING and FLAG_PADDING_NOT_NULL are set at the same time.
int	FOCUS_AFTER_DESCENDANTS	This view will get focus only if none of its descendants want it.
int	FOCUS_BEFORE_DESCENDANTS	This view will get focus before any of its descendants.
int	FOCUS_BLOCK_DESCENDANTS	This view will block any of its descendants from getting focus, even if they are focusable.
int	LAYOUT_MODE_CLIP_BOUNDS	This constant is a `layoutMode`.
int	LAYOUT_MODE_OPTICAL_BOUNDS	This constant is a `layoutMode`.
int	PERSISTENT_ALL_CACHES	Used to indicate that all drawing caches should be kept in memory.
int	PERSISTENT_ANIMATION_CACHE	Used to indicate that the animation drawing cache should be kept in memory.
int	PERSISTENT_NO_CACHE	Used to indicate that no drawing cache should be kept in memory.
int	PERSISTENT_SCROLLING_CACHE	Used to indicate that the scrolling drawing cache should be kept in memory.

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Inherited Constants

From class android.view.View

[Expand]

Inherited Fields

From class android.view.View

Public Constructors
	ViewGroup(Context context)
	ViewGroup(Context context, AttributeSet attrs)
	ViewGroup(Context context, AttributeSet attrs, int defStyle)

Public Methods
void	addChildrenForAccessibility(ArrayList<View> childrenForAccessibility) Adds the children of a given View for accessibility.
void	addFocusables(ArrayList<View> views, int direction, int focusableMode) Adds any focusable views that are descendants of this view (possibly including this view if it is focusable itself) to views.
boolean	addStatesFromChildren() Returns whether this ViewGroup's drawable states also include its children's drawable states.
void	addTouchables(ArrayList<View> views) Add any touchable views that are descendants of this view (possibly including this view if it is touchable itself) to views.
void	addView(View child, int index, ViewGroup.LayoutParams params) Adds a child view with the specified layout parameters.
void	addView(View child, ViewGroup.LayoutParams params) Adds a child view with the specified layout parameters.
void	addView(View child, int index) Adds a child view.
void	addView(View child) Adds a child view.
void	addView(View child, int width, int height) Adds a child view with this ViewGroup's default layout parameters and the specified width and height.
void	bringChildToFront(View child) Change the z order of the child so it's on top of all other children.
void	childDrawableStateChanged(View child) If `addStatesFromChildren()` is true, refreshes this group's drawable state (to include the states from its children).
void	childHasTransientStateChanged(View child, boolean childHasTransientState) Called when a child view has changed whether or not it is tracking transient state.
void	clearChildFocus(View child) Called when a child of this parent is giving up focus
void	clearDisappearingChildren() Removes any pending animations for views that have been removed.
void	clearFocus() Called when this view wants to give up focus.
void	dispatchConfigurationChanged(Configuration newConfig) Dispatch a notification about a resource configuration change down the view hierarchy.
void	dispatchDisplayHint(int hint) Dispatch a hint about whether this view is displayed.
boolean	dispatchDragEvent(DragEvent event) Detects if this View is enabled and has a drag event listener.
boolean	dispatchKeyEvent(KeyEvent event) Dispatch a key event to the next view on the focus path.
boolean	dispatchKeyEventPreIme(KeyEvent event) Dispatch a key event before it is processed by any input method associated with the view hierarchy.
boolean	dispatchKeyShortcutEvent(KeyEvent event) Dispatches a key shortcut event.
void	dispatchSetActivated(boolean activated) Dispatch setActivated to all of this View's children.
void	dispatchSetSelected(boolean selected) Dispatch setSelected to all of this View's children.
void	dispatchSystemUiVisibilityChanged(int visible) Dispatch callbacks to `setOnSystemUiVisibilityChangeListener(View.OnSystemUiVisibilityChangeListener)` down the view hierarchy.
boolean	dispatchTouchEvent(MotionEvent ev) Pass the touch screen motion event down to the target view, or this view if it is the target.
boolean	dispatchTrackballEvent(MotionEvent event) Pass a trackball motion event down to the focused view.
boolean	dispatchUnhandledMove(View focused, int direction) This method is the last chance for the focused view and its ancestors to respond to an arrow key.
void	dispatchWindowFocusChanged(boolean hasFocus) Called when the window containing this view gains or loses window focus.
void	dispatchWindowSystemUiVisiblityChanged(int visible) Dispatch callbacks to `onWindowSystemUiVisibilityChanged(int)` down the view hierarchy.
void	dispatchWindowVisibilityChanged(int visibility) Dispatch a window visibility change down the view hierarchy.
void	endViewTransition(View view) This method should always be called following an earlier call to `startViewTransition(View)`.
View	findFocus() Find the view in the hierarchy rooted at this view that currently has focus.
void	findViewsWithText(ArrayList<View> outViews, CharSequence text, int flags) Finds the Views that contain given text.
View	focusSearch(View focused, int direction) Find the nearest view in the specified direction that wants to take focus.
void	focusableViewAvailable(View v) Tells the parent that a new focusable view has become available.
boolean	gatherTransparentRegion(Region region) This is used by the RootView to perform an optimization when the view hierarchy contains one or several SurfaceView.
ViewGroup.LayoutParams	generateLayoutParams(AttributeSet attrs) Returns a new set of layout parameters based on the supplied attributes set.
View	getChildAt(int index) Returns the view at the specified position in the group.
int	getChildCount() Returns the number of children in the group.
static int	getChildMeasureSpec(int spec, int padding, int childDimension) Does the hard part of measureChildren: figuring out the MeasureSpec to pass to a particular child.
boolean	getChildVisibleRect(View child, Rect r, Point offset) Compute the visible part of a rectangular region defined in terms of a child view's coordinates.
boolean	getClipChildren() Returns whether ths group's children are clipped to their bounds before drawing.
int	getDescendantFocusability() Gets the descendant focusability of this view group.
View	getFocusedChild() Returns the focused child of this view, if any.
LayoutAnimationController	getLayoutAnimation() Returns the layout animation controller used to animate the group's children.
Animation.AnimationListener	getLayoutAnimationListener() Returns the animation listener to which layout animation events are sent.
int	getLayoutMode() Returns the basis of alignment during layout operations on this ViewGroup: either `LAYOUT_MODE_CLIP_BOUNDS` or `LAYOUT_MODE_OPTICAL_BOUNDS`.
LayoutTransition	getLayoutTransition() Gets the LayoutTransition object for this ViewGroup.
ViewGroupOverlay	getOverlay() Returns the ViewGroupOverlay for this view group, creating it if it does not yet exist.
int	getPersistentDrawingCache() Returns an integer indicating what types of drawing caches are kept in memory.
boolean	hasFocus() Returns true if this view has or contains focus
boolean	hasFocusable() Returns true if this view is focusable or if it contains a reachable View for which `hasFocusable()` returns true.
boolean	hasTransientState() Indicates whether the view is currently tracking transient state that the app should not need to concern itself with saving and restoring, but that the framework should take special note to preserve when possible.
int	indexOfChild(View child) Returns the position in the group of the specified child view.
final void	invalidateChild(View child, Rect dirty) Don't call or override this method.
ViewParent	invalidateChildInParent(int[] location, Rect dirty) Don't call or override this method.
boolean	isAlwaysDrawnWithCacheEnabled() Indicates whether this ViewGroup will always try to draw its children using their drawing cache.
boolean	isAnimationCacheEnabled() Indicates whether the children's drawing cache is used during a layout animation.
boolean	isMotionEventSplittingEnabled() Returns true if MotionEvents dispatched to this ViewGroup can be split to multiple children.
void	jumpDrawablesToCurrentState() Call `Drawable.jumpToCurrentState()` on all Drawable objects associated with this view.
final void	layout(int l, int t, int r, int b) Assign a size and position to a view and all of its descendants This is the second phase of the layout mechanism.
void	notifySubtreeAccessibilityStateChanged(View child, View source, int changeType) Notifies a view parent that the accessibility state of one of its descendants has changed and that the structure of the subtree is different.
final void	offsetDescendantRectToMyCoords(View descendant, Rect rect) Offset a rectangle that is in a descendant's coordinate space into our coordinate space.
final void	offsetRectIntoDescendantCoords(View descendant, Rect rect) Offset a rectangle that is in our coordinate space into an ancestor's coordinate space.
boolean	onInterceptHoverEvent(MotionEvent event) Implement this method to intercept hover events before they are handled by child views.
boolean	onInterceptTouchEvent(MotionEvent ev) Implement this method to intercept all touch screen motion events.
boolean	onRequestSendAccessibilityEvent(View child, AccessibilityEvent event) Called when a child has requested sending an `AccessibilityEvent` and gives an opportunity to its parent to augment the event.
void	recomputeViewAttributes(View child) Tell view hierarchy that the global view attributes need to be re-evaluated.
void	removeAllViews() Call this method to remove all child views from the ViewGroup.
void	removeAllViewsInLayout() Called by a ViewGroup subclass to remove child views from itself, when it must first know its size on screen before it can calculate how many child views it will render.
void	removeView(View view) Note: do not invoke this method from `draw(android.graphics.Canvas)`, `onDraw(android.graphics.Canvas)`, `dispatchDraw(android.graphics.Canvas)` or any related method.
void	removeViewAt(int index) Removes the view at the specified position in the group.
void	removeViewInLayout(View view) Removes a view during layout.
void	removeViews(int start, int count) Removes the specified range of views from the group.
void	removeViewsInLayout(int start, int count) Removes a range of views during layout.
void	requestChildFocus(View child, View focused) Called when a child of this parent wants focus
boolean	requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) Called when a child of this group wants a particular rectangle to be positioned onto the screen.
void	requestDisallowInterceptTouchEvent(boolean disallowIntercept) Called when a child does not want this parent and its ancestors to intercept touch events with `onInterceptTouchEvent(MotionEvent)`.
boolean	requestFocus(int direction, Rect previouslyFocusedRect) Call this to try to give focus to a specific view or to one of its descendants and give it hints about the direction and a specific rectangle that the focus is coming from. Looks for a view to give focus to respecting the setting specified by `getDescendantFocusability()`.
boolean	requestSendAccessibilityEvent(View child, AccessibilityEvent event) Called by a child to request from its parent to send an `AccessibilityEvent`.
void	requestTransparentRegion(View child) Called when a child wants the view hierarchy to gather and report transparent regions to the window compositor.
void	scheduleLayoutAnimation() Schedules the layout animation to be played after the next layout pass of this view group.
void	setAddStatesFromChildren(boolean addsStates) Sets whether this ViewGroup's drawable states also include its children's drawable states.
void	setAlwaysDrawnWithCacheEnabled(boolean always) Indicates whether this ViewGroup will always try to draw its children using their drawing cache.
void	setAnimationCacheEnabled(boolean enabled) Enables or disables the children's drawing cache during a layout animation.
void	setClipChildren(boolean clipChildren) By default, children are clipped to their bounds before drawing.
void	setClipToPadding(boolean clipToPadding) By default, children are clipped to the padding of the ViewGroup.
void	setDescendantFocusability(int focusability) Set the descendant focusability of this view group.
void	setLayoutAnimation(LayoutAnimationController controller) Sets the layout animation controller used to animate the group's children after the first layout.
void	setLayoutAnimationListener(Animation.AnimationListener animationListener) Specifies the animation listener to which layout animation events must be sent.
void	setLayoutMode(int layoutMode) Sets the basis of alignment during the layout of this ViewGroup.
void	setLayoutTransition(LayoutTransition transition) Sets the LayoutTransition object for this ViewGroup.
void	setMotionEventSplittingEnabled(boolean split) Enable or disable the splitting of MotionEvents to multiple children during touch event dispatch.
void	setOnHierarchyChangeListener(ViewGroup.OnHierarchyChangeListener listener) Register a callback to be invoked when a child is added to or removed from this view.
void	setPersistentDrawingCache(int drawingCacheToKeep) Indicates what types of drawing caches should be kept in memory after they have been created.
boolean	shouldDelayChildPressedState() Return true if the pressed state should be delayed for children or descendants of this ViewGroup.
boolean	showContextMenuForChild(View originalView) Bring up a context menu for the specified view or its ancestors.
ActionMode	startActionModeForChild(View originalView, ActionMode.Callback callback) Start an action mode for the specified view.
void	startLayoutAnimation() Runs the layout animation.
void	startViewTransition(View view) This method tells the ViewGroup that the given View object, which should have this ViewGroup as its parent, should be kept around (re-displayed when the ViewGroup draws its children) even if it is removed from its parent.
void	updateViewLayout(View view, ViewGroup.LayoutParams params)

Protected Methods
boolean	addViewInLayout(View child, int index, ViewGroup.LayoutParams params, boolean preventRequestLayout) Adds a view during layout.
boolean	addViewInLayout(View child, int index, ViewGroup.LayoutParams params) Adds a view during layout.
void	attachLayoutAnimationParameters(View child, ViewGroup.LayoutParams params, int index, int count) Subclasses should override this method to set layout animation parameters on the supplied child.
void	attachViewToParent(View child, int index, ViewGroup.LayoutParams params) Attaches a view to this view group.
boolean	canAnimate() Indicates whether the view group has the ability to animate its children after the first layout.
boolean	checkLayoutParams(ViewGroup.LayoutParams p)
void	cleanupLayoutState(View child) Prevents the specified child to be laid out during the next layout pass.
void	debug(int depth) Prints information about this view in the log output, with the tag `VIEW_LOG_TAG`.
void	detachAllViewsFromParent() Detaches all views from the parent.
void	detachViewFromParent(View child) Detaches a view from its parent.
void	detachViewFromParent(int index) Detaches a view from its parent.
void	detachViewsFromParent(int start, int count) Detaches a range of views from their parents.
void	dispatchDraw(Canvas canvas) Called by draw to draw the child views.
void	dispatchFreezeSelfOnly(SparseArray<Parcelable> container) Perform dispatching of a `saveHierarchyState(android.util.SparseArray)` freeze()} to only this view, not to its children.
boolean	dispatchGenericFocusedEvent(MotionEvent event) Dispatch a generic motion event to the currently focused view.
boolean	dispatchGenericPointerEvent(MotionEvent event) Dispatch a generic motion event to the view under the first pointer.
boolean	dispatchHoverEvent(MotionEvent event) Dispatch a hover event.
void	dispatchRestoreInstanceState(SparseArray<Parcelable> container) Called by `restoreHierarchyState(android.util.SparseArray)` to retrieve the state for this view and its children.
void	dispatchSaveInstanceState(SparseArray<Parcelable> container) Called by `saveHierarchyState(android.util.SparseArray)` to store the state for this view and its children.
void	dispatchSetPressed(boolean pressed) Dispatch setPressed to all of this View's children.
void	dispatchThawSelfOnly(SparseArray<Parcelable> container) Perform dispatching of a `restoreHierarchyState(android.util.SparseArray)` to only this view, not to its children.
void	dispatchVisibilityChanged(View changedView, int visibility) Dispatch a view visibility change down the view hierarchy.
boolean	drawChild(Canvas canvas, View child, long drawingTime) Draw one child of this View Group.
void	drawableStateChanged() This function is called whenever the state of the view changes in such a way that it impacts the state of drawables being shown.
boolean	fitSystemWindows(Rect insets) Called by the view hierarchy when the content insets for a window have changed, to allow it to adjust its content to fit within those windows.
ViewGroup.LayoutParams	generateDefaultLayoutParams() Returns a set of default layout parameters.
ViewGroup.LayoutParams	generateLayoutParams(ViewGroup.LayoutParams p) Returns a safe set of layout parameters based on the supplied layout params.
int	getChildDrawingOrder(int childCount, int i) Returns the index of the child to draw for this iteration.
boolean	getChildStaticTransformation(View child, Transformation t) Sets `t` to be the static transformation of the child, if set, returning a boolean to indicate whether a static transform was set.
boolean	isChildrenDrawingOrderEnabled() Indicates whether the ViewGroup is drawing its children in the order defined by `getChildDrawingOrder(int, int)`.
boolean	isChildrenDrawnWithCacheEnabled() Indicates whether the ViewGroup is currently drawing its children using their drawing cache.
void	measureChild(View child, int parentWidthMeasureSpec, int parentHeightMeasureSpec) Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding.
void	measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed, int parentHeightMeasureSpec, int heightUsed) Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding and margins.
void	measureChildren(int widthMeasureSpec, int heightMeasureSpec) Ask all of the children of this view to measure themselves, taking into account both the MeasureSpec requirements for this view and its padding.
void	onAnimationEnd() Invoked by a parent ViewGroup to notify the end of the animation currently associated with this view.
void	onAnimationStart() Invoked by a parent ViewGroup to notify the start of the animation currently associated with this view.
void	onAttachedToWindow() This is called when the view is attached to a window.
int[]	onCreateDrawableState(int extraSpace) Generate the new `Drawable` state for this view.
void	onDetachedFromWindow() This is called when the view is detached from a window.
abstract void	onLayout(boolean changed, int l, int t, int r, int b) Called from layout when this view should assign a size and position to each of its children.
boolean	onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect) Look for a descendant to call `requestFocus()` on.
void	removeDetachedView(View child, boolean animate) Finishes the removal of a detached view.
void	setChildrenDrawingCacheEnabled(boolean enabled) Enables or disables the drawing cache for each child of this view group.
void	setChildrenDrawingOrderEnabled(boolean enabled) Tells the ViewGroup whether to draw its children in the order defined by the method `getChildDrawingOrder(int, int)`.
void	setChildrenDrawnWithCacheEnabled(boolean enabled) Tells the ViewGroup to draw its children using their drawing cache.
void	setStaticTransformationsEnabled(boolean enabled) When this property is set to true, this ViewGroup supports static transformations on children; this causes `getChildStaticTransformation(View, android.view.animation.Transformation)` to be invoked when a child is drawn.

[Expand]

Inherited Methods

From class android.view.View

void	addChildrenForAccessibility(ArrayList<View> children) Adds the children of a given View for accessibility.
void	addFocusables(ArrayList<View> views, int direction, int focusableMode) Adds any focusable views that are descendants of this view (possibly including this view if it is focusable itself) to views.
void	addFocusables(ArrayList<View> views, int direction) Add any focusable views that are descendants of this view (possibly including this view if it is focusable itself) to views.
void	addOnAttachStateChangeListener(View.OnAttachStateChangeListener listener) Add a listener for attach state changes.
void	addOnLayoutChangeListener(View.OnLayoutChangeListener listener) Add a listener that will be called when the bounds of the view change due to layout processing.
void	addTouchables(ArrayList<View> views) Add any touchable views that are descendants of this view (possibly including this view if it is touchable itself) to views.
ViewPropertyAnimator	animate() This method returns a ViewPropertyAnimator object, which can be used to animate specific properties on this View.
void	announceForAccessibility(CharSequence text) Convenience method for sending a `TYPE_ANNOUNCEMENT` `AccessibilityEvent` to make an announcement which is related to some sort of a context change for which none of the events representing UI transitions is a good fit.
boolean	awakenScrollBars(int startDelay) Trigger the scrollbars to draw.
boolean	awakenScrollBars(int startDelay, boolean invalidate) Trigger the scrollbars to draw.
boolean	awakenScrollBars() Trigger the scrollbars to draw.
void	bringToFront() Change the view's z order in the tree, so it's on top of other sibling views.
void	buildDrawingCache() Calling this method is equivalent to calling `buildDrawingCache(false)`.
void	buildDrawingCache(boolean autoScale) Forces the drawing cache to be built if the drawing cache is invalid.
void	buildLayer() Forces this view's layer to be created and this view to be rendered into its layer.
boolean	callOnClick() Directly call any attached OnClickListener.
boolean	canResolveLayoutDirection() Check if layout direction resolution can be done.
boolean	canResolveTextAlignment() Check if text alignment resolution can be done.
boolean	canResolveTextDirection() Check if text direction resolution can be done.
boolean	canScrollHorizontally(int direction) Check if this view can be scrolled horizontally in a certain direction.
boolean	canScrollVertically(int direction) Check if this view can be scrolled vertically in a certain direction.
void	cancelLongPress() Cancels a pending long press.
final void	cancelPendingInputEvents() Cancel any deferred high-level input events that were previously posted to the event queue.
boolean	checkInputConnectionProxy(View view) Called by the `InputMethodManager` when a view who is not the current input connection target is trying to make a call on the manager.
void	clearAnimation() Cancels any animations for this view.
void	clearFocus() Called when this view wants to give up focus.
static int	combineMeasuredStates(int curState, int newState) Merge two states as returned by `getMeasuredState()`.
int	computeHorizontalScrollExtent() Compute the horizontal extent of the horizontal scrollbar's thumb within the horizontal range.
int	computeHorizontalScrollOffset() Compute the horizontal offset of the horizontal scrollbar's thumb within the horizontal range.
int	computeHorizontalScrollRange() Compute the horizontal range that the horizontal scrollbar represents.
void	computeScroll() Called by a parent to request that a child update its values for mScrollX and mScrollY if necessary.
int	computeVerticalScrollExtent() Compute the vertical extent of the horizontal scrollbar's thumb within the vertical range.
int	computeVerticalScrollOffset() Compute the vertical offset of the vertical scrollbar's thumb within the horizontal range.
int	computeVerticalScrollRange() Compute the vertical range that the vertical scrollbar represents.
AccessibilityNodeInfo	createAccessibilityNodeInfo() Returns an `AccessibilityNodeInfo` representing this view from the point of view of an `AccessibilityService`.
void	createContextMenu(ContextMenu menu) Show the context menu for this view.
void	destroyDrawingCache() Frees the resources used by the drawing cache.
void	dispatchConfigurationChanged(Configuration newConfig) Dispatch a notification about a resource configuration change down the view hierarchy.
void	dispatchDisplayHint(int hint) Dispatch a hint about whether this view is displayed.
boolean	dispatchDragEvent(DragEvent event) Detects if this View is enabled and has a drag event listener.
void	dispatchDraw(Canvas canvas) Called by draw to draw the child views.
boolean	dispatchGenericFocusedEvent(MotionEvent event) Dispatch a generic motion event to the currently focused view.
boolean	dispatchGenericMotionEvent(MotionEvent event) Dispatch a generic motion event.
boolean	dispatchGenericPointerEvent(MotionEvent event) Dispatch a generic motion event to the view under the first pointer.
boolean	dispatchHoverEvent(MotionEvent event) Dispatch a hover event.
boolean	dispatchKeyEvent(KeyEvent event) Dispatch a key event to the next view on the focus path.
boolean	dispatchKeyEventPreIme(KeyEvent event) Dispatch a key event before it is processed by any input method associated with the view hierarchy.
boolean	dispatchKeyShortcutEvent(KeyEvent event) Dispatches a key shortcut event.
boolean	dispatchPopulateAccessibilityEvent(AccessibilityEvent event) Dispatches an `AccessibilityEvent` to the `View` first and then to its children for adding their text content to the event.
void	dispatchRestoreInstanceState(SparseArray<Parcelable> container) Called by `restoreHierarchyState(android.util.SparseArray)` to retrieve the state for this view and its children.
void	dispatchSaveInstanceState(SparseArray<Parcelable> container) Called by `saveHierarchyState(android.util.SparseArray)` to store the state for this view and its children.
void	dispatchSetActivated(boolean activated) Dispatch setActivated to all of this View's children.
void	dispatchSetPressed(boolean pressed) Dispatch setPressed to all of this View's children.
void	dispatchSetSelected(boolean selected) Dispatch setSelected to all of this View's children.
void	dispatchSystemUiVisibilityChanged(int visibility) Dispatch callbacks to `setOnSystemUiVisibilityChangeListener(View.OnSystemUiVisibilityChangeListener)` down the view hierarchy.
boolean	dispatchTouchEvent(MotionEvent event) Pass the touch screen motion event down to the target view, or this view if it is the target.
boolean	dispatchTrackballEvent(MotionEvent event) Pass a trackball motion event down to the focused view.
boolean	dispatchUnhandledMove(View focused, int direction) This method is the last chance for the focused view and its ancestors to respond to an arrow key.
void	dispatchVisibilityChanged(View changedView, int visibility) Dispatch a view visibility change down the view hierarchy.
void	dispatchWindowFocusChanged(boolean hasFocus) Called when the window containing this view gains or loses window focus.
void	dispatchWindowSystemUiVisiblityChanged(int visible) Dispatch callbacks to `onWindowSystemUiVisibilityChanged(int)` down the view hierarchy.
void	dispatchWindowVisibilityChanged(int visibility) Dispatch a window visibility change down the view hierarchy.
void	draw(Canvas canvas) Manually render this view (and all of its children) to the given Canvas.
void	drawableStateChanged() This function is called whenever the state of the view changes in such a way that it impacts the state of drawables being shown.
View	findFocus() Find the view in the hierarchy rooted at this view that currently has focus.
final View	findViewById(int id) Look for a child view with the given id.
final View	findViewWithTag(Object tag) Look for a child view with the given tag.
void	findViewsWithText(ArrayList<View> outViews, CharSequence searched, int flags) Finds the Views that contain given text.
boolean	fitSystemWindows(Rect insets) Called by the view hierarchy when the content insets for a window have changed, to allow it to adjust its content to fit within those windows.
View	focusSearch(int direction) Find the nearest view in the specified direction that can take focus.
void	forceLayout() Forces this view to be laid out during the next layout pass.
static int	generateViewId() Generate a value suitable for use in `setId(int)`.
int	getAccessibilityLiveRegion() Gets the live region mode for this View.
AccessibilityNodeProvider	getAccessibilityNodeProvider() Gets the provider for managing a virtual view hierarchy rooted at this View and reported to `AccessibilityService`s that explore the window content.
float	getAlpha() The opacity of the view.
Animation	getAnimation() Get the animation currently associated with this view.
IBinder	getApplicationWindowToken() Retrieve a unique token identifying the top-level "real" window of the window that this view is attached to.
Drawable	getBackground() Gets the background drawable
int	getBaseline() Return the offset of the widget's text baseline from the widget's top boundary.
final int	getBottom() Bottom position of this view relative to its parent.
float	getBottomFadingEdgeStrength() Returns the strength, or intensity, of the bottom faded edge.
int	getBottomPaddingOffset() Amount by which to extend the bottom fading region.
float	getCameraDistance() Gets the distance along the Z axis from the camera to this view.
Rect	getClipBounds() Returns a copy of the current `clipBounds`.
CharSequence	getContentDescription() Gets the `View` description.
final Context	getContext() Returns the context the view is running in, through which it can access the current theme, resources, etc.
ContextMenu.ContextMenuInfo	getContextMenuInfo() Views should implement this if they have extra information to associate with the context menu.
static int	getDefaultSize(int size, int measureSpec) Utility to return a default size.
Display	getDisplay() Gets the logical display to which the view's window has been attached.
final int[]	getDrawableState() Return an array of resource IDs of the drawable states representing the current state of the view.
Bitmap	getDrawingCache(boolean autoScale) Returns the bitmap in which this view drawing is cached.
Bitmap	getDrawingCache() Calling this method is equivalent to calling `getDrawingCache(false)`.
int	getDrawingCacheBackgroundColor()
int	getDrawingCacheQuality() Returns the quality of the drawing cache.
void	getDrawingRect(Rect outRect) Return the visible drawing bounds of your view.
long	getDrawingTime() Return the time at which the drawing of the view hierarchy started.
boolean	getFilterTouchesWhenObscured() Gets whether the framework should discard touches when the view's window is obscured by another visible window.
boolean	getFitsSystemWindows() Check for state of `setFitsSystemWindows(boolean)`.
ArrayList<View>	getFocusables(int direction) Find and return all focusable views that are descendants of this view, possibly including this view if it is focusable itself.
void	getFocusedRect(Rect r) When a view has focus and the user navigates away from it, the next view is searched for starting from the rectangle filled in by this method.
boolean	getGlobalVisibleRect(Rect r, Point globalOffset) If some part of this view is not clipped by any of its parents, then return that area in r in global (root) coordinates.
final boolean	getGlobalVisibleRect(Rect r)
Handler	getHandler()
final int	getHeight() Return the height of your view.
void	getHitRect(Rect outRect) Hit rectangle in parent's coordinates
int	getHorizontalFadingEdgeLength() Returns the size of the horizontal faded edges used to indicate that more content in this view is visible.
int	getHorizontalScrollbarHeight() Returns the height of the horizontal scrollbar.
int	getId() Returns this view's identifier.
int	getImportantForAccessibility() Gets the mode for determining whether this View is important for accessibility which is if it fires accessibility events and if it is reported to accessibility services that query the screen.
boolean	getKeepScreenOn() Returns whether the screen should remain on, corresponding to the current value of `KEEP_SCREEN_ON`.
KeyEvent.DispatcherState	getKeyDispatcherState() Return the global `KeyEvent.DispatcherState` for this view's window.
int	getLabelFor() Gets the id of a view for which this view serves as a label for accessibility purposes.
int	getLayerType() Indicates what type of layer is currently associated with this view.
int	getLayoutDirection() Returns the resolved layout direction for this view.
ViewGroup.LayoutParams	getLayoutParams() Get the LayoutParams associated with this view.
final int	getLeft() Left position of this view relative to its parent.
float	getLeftFadingEdgeStrength() Returns the strength, or intensity, of the left faded edge.
int	getLeftPaddingOffset() Amount by which to extend the left fading region.
final boolean	getLocalVisibleRect(Rect r)
void	getLocationInWindow(int[] location) Computes the coordinates of this view in its window.
void	getLocationOnScreen(int[] location) Computes the coordinates of this view on the screen.
Matrix	getMatrix() The transform matrix of this view, which is calculated based on the current roation, scale, and pivot properties.
final int	getMeasuredHeight() Like `getMeasuredHeightAndState()`, but only returns the raw width component (that is the result is masked by `MEASURED_SIZE_MASK`).
final int	getMeasuredHeightAndState() Return the full height measurement information for this view as computed by the most recent call to `measure(int, int)`.
final int	getMeasuredState() Return only the state bits of `getMeasuredWidthAndState()` and `getMeasuredHeightAndState()`, combined into one integer.
final int	getMeasuredWidth() Like `getMeasuredWidthAndState()`, but only returns the raw width component (that is the result is masked by `MEASURED_SIZE_MASK`).
final int	getMeasuredWidthAndState() Return the full width measurement information for this view as computed by the most recent call to `measure(int, int)`.
int	getMinimumHeight() Returns the minimum height of the view.
int	getMinimumWidth() Returns the minimum width of the view.
int	getNextFocusDownId() Gets the id of the view to use when the next focus is `FOCUS_DOWN`.
int	getNextFocusForwardId() Gets the id of the view to use when the next focus is `FOCUS_FORWARD`.
int	getNextFocusLeftId() Gets the id of the view to use when the next focus is `FOCUS_LEFT`.
int	getNextFocusRightId() Gets the id of the view to use when the next focus is `FOCUS_RIGHT`.
int	getNextFocusUpId() Gets the id of the view to use when the next focus is `FOCUS_UP`.
View.OnFocusChangeListener	getOnFocusChangeListener() Returns the focus-change callback registered for this view.
int	getOverScrollMode() Returns the over-scroll mode for this view.
ViewOverlay	getOverlay() Returns the overlay for this view, creating it if it does not yet exist.
int	getPaddingBottom() Returns the bottom padding of this view.
int	getPaddingEnd() Returns the end padding of this view depending on its resolved layout direction.
int	getPaddingLeft() Returns the left padding of this view.
int	getPaddingRight() Returns the right padding of this view.
int	getPaddingStart() Returns the start padding of this view depending on its resolved layout direction.
int	getPaddingTop() Returns the top padding of this view.
final ViewParent	getParent() Gets the parent of this view.
ViewParent	getParentForAccessibility() Gets the parent for accessibility purposes.
float	getPivotX() The x location of the point around which the view is `rotated` and `scaled`.
float	getPivotY() The y location of the point around which the view is `rotated` and `scaled`.
Resources	getResources() Returns the resources associated with this view.
final int	getRight() Right position of this view relative to its parent.
float	getRightFadingEdgeStrength() Returns the strength, or intensity, of the right faded edge.
int	getRightPaddingOffset() Amount by which to extend the right fading region.
View	getRootView() Finds the topmost view in the current view hierarchy.
float	getRotation() The degrees that the view is rotated around the pivot point.
float	getRotationX() The degrees that the view is rotated around the horizontal axis through the pivot point.
float	getRotationY() The degrees that the view is rotated around the vertical axis through the pivot point.
float	getScaleX() The amount that the view is scaled in x around the pivot point, as a proportion of the view's unscaled width.
float	getScaleY() The amount that the view is scaled in y around the pivot point, as a proportion of the view's unscaled height.
int	getScrollBarDefaultDelayBeforeFade() Returns the delay before scrollbars fade.
int	getScrollBarFadeDuration() Returns the scrollbar fade duration.
int	getScrollBarSize() Returns the scrollbar size.
int	getScrollBarStyle() Returns the current scrollbar style.
final int	getScrollX() Return the scrolled left position of this view.
final int	getScrollY() Return the scrolled top position of this view.
int	getSolidColor() Override this if your view is known to always be drawn on top of a solid color background, and needs to draw fading edges.
int	getSuggestedMinimumHeight() Returns the suggested minimum height that the view should use.
int	getSuggestedMinimumWidth() Returns the suggested minimum width that the view should use.
int	getSystemUiVisibility() Returns the last `setSystemUiVisibility(int)` that this view has requested.
Object	getTag(int key) Returns the tag associated with this view and the specified key.
Object	getTag() Returns this view's tag.
int	getTextAlignment() Return the resolved text alignment.
int	getTextDirection() Return the resolved text direction.
final int	getTop() Top position of this view relative to its parent.
float	getTopFadingEdgeStrength() Returns the strength, or intensity, of the top faded edge.
int	getTopPaddingOffset() Amount by which to extend the top fading region.
TouchDelegate	getTouchDelegate() Gets the TouchDelegate for this View.
ArrayList<View>	getTouchables() Find and return all touchable views that are descendants of this view, possibly including this view if it is touchable itself.
float	getTranslationX() The horizontal location of this view relative to its `left` position.
float	getTranslationY() The horizontal location of this view relative to its `top` position.
int	getVerticalFadingEdgeLength() Returns the size of the vertical faded edges used to indicate that more content in this view is visible.
int	getVerticalScrollbarPosition()
int	getVerticalScrollbarWidth() Returns the width of the vertical scrollbar.
ViewTreeObserver	getViewTreeObserver() Returns the ViewTreeObserver for this view's hierarchy.
int	getVisibility() Returns the visibility status for this view.
final int	getWidth() Return the width of the your view.
int	getWindowAttachCount()
WindowId	getWindowId() Retrieve the `WindowId` for the window this view is currently attached to.
int	getWindowSystemUiVisibility() Returns the current system UI visibility that is currently set for the entire window.
IBinder	getWindowToken() Retrieve a unique token identifying the window this view is attached to.
int	getWindowVisibility() Returns the current visibility of the window this view is attached to (either `GONE`, `INVISIBLE`, or `VISIBLE`).
void	getWindowVisibleDisplayFrame(Rect outRect) Retrieve the overall visible display size in which the window this view is attached to has been positioned in.
float	getX() The visual x position of this view, in pixels.
float	getY() The visual y position of this view, in pixels.
boolean	hasFocus() Returns true if this view has focus iteself, or is the ancestor of the view that has focus.
boolean	hasFocusable() Returns true if this view is focusable or if it contains a reachable View for which `hasFocusable()` returns true.
boolean	hasOnClickListeners() Return whether this view has an attached OnClickListener.
boolean	hasOverlappingRendering() Returns whether this View has content which overlaps.
boolean	hasTransientState() Indicates whether the view is currently tracking transient state that the app should not need to concern itself with saving and restoring, but that the framework should take special note to preserve when possible.
boolean	hasWindowFocus() Returns true if this view is in a window that currently has window focus.
static View	inflate(Context context, int resource, ViewGroup root) Inflate a view from an XML resource.
void	initializeFadingEdge(TypedArray a) Initializes the fading edges from a given set of styled attributes.
void	initializeScrollbars(TypedArray a) Initializes the scrollbars from a given set of styled attributes.
void	invalidate(Rect dirty) Mark the area defined by dirty as needing to be drawn.
void	invalidate(int l, int t, int r, int b) Mark the area defined by the rect (l,t,r,b) as needing to be drawn.
void	invalidate() Invalidate the whole view.
void	invalidateDrawable(Drawable drawable) Invalidates the specified Drawable.
boolean	isActivated() Indicates the activation state of this view.
boolean	isAttachedToWindow() Returns true if this view is currently attached to a window.
boolean	isClickable() Indicates whether this view reacts to click events or not.
boolean	isDirty() True if this view has changed since the last time being drawn.
boolean	isDrawingCacheEnabled() Indicates whether the drawing cache is enabled for this view.
boolean	isDuplicateParentStateEnabled() Indicates whether this duplicates its drawable state from its parent.
boolean	isEnabled() Returns the enabled status for this view.
final boolean	isFocusable() Returns whether this View is able to take focus.
final boolean	isFocusableInTouchMode() When a view is focusable, it may not want to take focus when in touch mode.
boolean	isFocused() Returns true if this view has focus
boolean	isHapticFeedbackEnabled()
boolean	isHardwareAccelerated() Indicates whether this view is attached to a hardware accelerated window or not.
boolean	isHorizontalFadingEdgeEnabled() Indicate whether the horizontal edges are faded when the view is scrolled horizontally.
boolean	isHorizontalScrollBarEnabled() Indicate whether the horizontal scrollbar should be drawn or not.
boolean	isHovered() Returns true if the view is currently hovered.
boolean	isInEditMode() Indicates whether this View is currently in edit mode.
boolean	isInLayout() Returns whether the view hierarchy is currently undergoing a layout pass.
boolean	isInTouchMode() Returns whether the device is currently in touch mode.
boolean	isLaidOut() Returns true if this view has been through at least one layout since it was last attached to or detached from a window.
boolean	isLayoutDirectionResolved()
boolean	isLayoutRequested() Indicates whether or not this view's layout will be requested during the next hierarchy layout pass.
boolean	isLongClickable() Indicates whether this view reacts to long click events or not.
boolean	isOpaque() Indicates whether this View is opaque.
boolean	isPaddingOffsetRequired() If the View draws content inside its padding and enables fading edges, it needs to support padding offsets.
boolean	isPaddingRelative() Return if the padding as been set thru relative values `setPaddingRelative(int, int, int, int)` or thru
boolean	isPressed() Indicates whether the view is currently in pressed state.
boolean	isSaveEnabled() Indicates whether this view will save its state (that is, whether its `onSaveInstanceState()` method will be called).
boolean	isSaveFromParentEnabled() Indicates whether the entire hierarchy under this view will save its state when a state saving traversal occurs from its parent.
boolean	isScrollContainer() Indicates whether this view is one of the set of scrollable containers in its window.
boolean	isScrollbarFadingEnabled() Returns true if scrollbars will fade when this view is not scrolling
boolean	isSelected() Indicates the selection state of this view.
boolean	isShown() Returns the visibility of this view and all of its ancestors
boolean	isSoundEffectsEnabled()
boolean	isTextAlignmentResolved()
boolean	isTextDirectionResolved()
boolean	isVerticalFadingEdgeEnabled() Indicate whether the vertical edges are faded when the view is scrolled horizontally.
boolean	isVerticalScrollBarEnabled() Indicate whether the vertical scrollbar should be drawn or not.
void	jumpDrawablesToCurrentState() Call `Drawable.jumpToCurrentState()` on all Drawable objects associated with this view.
void	layout(int l, int t, int r, int b) Assign a size and position to a view and all of its descendants This is the second phase of the layout mechanism.
final void	measure(int widthMeasureSpec, int heightMeasureSpec) This is called to find out how big a view should be.
static int[]	mergeDrawableStates(int[] baseState, int[] additionalState) Merge your own state values in `additionalState` into the base state values `baseState` that were returned by `onCreateDrawableState(int)`.
void	offsetLeftAndRight(int offset) Offset this view's horizontal location by the specified amount of pixels.
void	offsetTopAndBottom(int offset) Offset this view's vertical location by the specified number of pixels.
void	onAnimationEnd() Invoked by a parent ViewGroup to notify the end of the animation currently associated with this view.
void	onAnimationStart() Invoked by a parent ViewGroup to notify the start of the animation currently associated with this view.
void	onAttachedToWindow() This is called when the view is attached to a window.
void	onCancelPendingInputEvents() Called as the result of a call to `cancelPendingInputEvents()` on this view or a parent view.
boolean	onCheckIsTextEditor() Check whether the called view is a text editor, in which case it would make sense to automatically display a soft input window for it.
void	onConfigurationChanged(Configuration newConfig) Called when the current configuration of the resources being used by the application have changed.
void	onCreateContextMenu(ContextMenu menu) Views should implement this if the view itself is going to add items to the context menu.
int[]	onCreateDrawableState(int extraSpace) Generate the new `Drawable` state for this view.
InputConnection	onCreateInputConnection(EditorInfo outAttrs) Create a new InputConnection for an InputMethod to interact with the view.
void	onDetachedFromWindow() This is called when the view is detached from a window.
void	onDisplayHint(int hint) Gives this view a hint about whether is displayed or not.
boolean	onDragEvent(DragEvent event) Handles drag events sent by the system following a call to `startDrag()`.
void	onDraw(Canvas canvas) Implement this to do your drawing.
final void	onDrawScrollBars(Canvas canvas) Request the drawing of the horizontal and the vertical scrollbar.
boolean	onFilterTouchEventForSecurity(MotionEvent event) Filter the touch event to apply security policies.
void	onFinishInflate() Finalize inflating a view from XML.
void	onFinishTemporaryDetach() Called after `onStartTemporaryDetach()` when the container is done changing the view.
void	onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) Called by the view system when the focus state of this view changes.
boolean	onGenericMotionEvent(MotionEvent event) Implement this method to handle generic motion events.
void	onHoverChanged(boolean hovered) Implement this method to handle hover state changes.
boolean	onHoverEvent(MotionEvent event) Implement this method to handle hover events.
void	onInitializeAccessibilityEvent(AccessibilityEvent event) Initializes an `AccessibilityEvent` with information about this View which is the event source.
void	onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) Initializes an `AccessibilityNodeInfo` with information about this view.
boolean	onKeyDown(int keyCode, KeyEvent event) Default implementation of `KeyEvent.Callback.onKeyDown()`: perform press of the view when `KEYCODE_DPAD_CENTER` or `KEYCODE_ENTER` is released, if the view is enabled and clickable.
boolean	onKeyLongPress(int keyCode, KeyEvent event) Default implementation of `KeyEvent.Callback.onKeyLongPress()`: always returns false (doesn't handle the event).
boolean	onKeyMultiple(int keyCode, int repeatCount, KeyEvent event) Default implementation of `KeyEvent.Callback.onKeyMultiple()`: always returns false (doesn't handle the event).
boolean	onKeyPreIme(int keyCode, KeyEvent event) Handle a key event before it is processed by any input method associated with the view hierarchy.
boolean	onKeyShortcut(int keyCode, KeyEvent event) Called on the focused view when a key shortcut event is not handled.
boolean	onKeyUp(int keyCode, KeyEvent event) Default implementation of `KeyEvent.Callback.onKeyUp()`: perform clicking of the view when `KEYCODE_DPAD_CENTER` or `KEYCODE_ENTER` is released.
void	onLayout(boolean changed, int left, int top, int right, int bottom) Called from layout when this view should assign a size and position to each of its children.
void	onMeasure(int widthMeasureSpec, int heightMeasureSpec) Measure the view and its content to determine the measured width and the measured height.
void	onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) Called by `overScrollBy(int, int, int, int, int, int, int, int, boolean)` to respond to the results of an over-scroll operation.
void	onPopulateAccessibilityEvent(AccessibilityEvent event) Called from `dispatchPopulateAccessibilityEvent(AccessibilityEvent)` giving a chance to this View to populate the accessibility event with its text content.
void	onRestoreInstanceState(Parcelable state) Hook allowing a view to re-apply a representation of its internal state that had previously been generated by `onSaveInstanceState()`.
void	onRtlPropertiesChanged(int layoutDirection) Called when any RTL property (layout direction or text direction or text alignment) has been changed.
Parcelable	onSaveInstanceState() Hook allowing a view to generate a representation of its internal state that can later be used to create a new instance with that same state.
void	onScreenStateChanged(int screenState) This method is called whenever the state of the screen this view is attached to changes.
void	onScrollChanged(int l, int t, int oldl, int oldt) This is called in response to an internal scroll in this view (i.e., the view scrolled its own contents).
boolean	onSetAlpha(int alpha) Invoked if there is a Transform that involves alpha.
void	onSizeChanged(int w, int h, int oldw, int oldh) This is called during layout when the size of this view has changed.
void	onStartTemporaryDetach() This is called when a container is going to temporarily detach a child, with `ViewGroup.detachViewFromParent`.
boolean	onTouchEvent(MotionEvent event) Implement this method to handle touch screen motion events.
boolean	onTrackballEvent(MotionEvent event) Implement this method to handle trackball motion events.
void	onVisibilityChanged(View changedView, int visibility) Called when the visibility of the view or an ancestor of the view is changed.
void	onWindowFocusChanged(boolean hasWindowFocus) Called when the window containing this view gains or loses focus.
void	onWindowSystemUiVisibilityChanged(int visible) Override to find out when the window's requested system UI visibility has changed, that is the value returned by `getWindowSystemUiVisibility()`.
void	onWindowVisibilityChanged(int visibility) Called when the window containing has change its visibility (between `GONE`, `INVISIBLE`, and `VISIBLE`).
boolean	overScrollBy(int deltaX, int deltaY, int scrollX, int scrollY, int scrollRangeX, int scrollRangeY, int maxOverScrollX, int maxOverScrollY, boolean isTouchEvent) Scroll the view with standard behavior for scrolling beyond the normal content boundaries.
boolean	performAccessibilityAction(int action, Bundle arguments) Performs the specified accessibility action on the view.
boolean	performClick() Call this view's OnClickListener, if it is defined.
boolean	performHapticFeedback(int feedbackConstant) BZZZTT!!1! Provide haptic feedback to the user for this view.
boolean	performHapticFeedback(int feedbackConstant, int flags) BZZZTT!!1! Like `performHapticFeedback(int)`, with additional options.
boolean	performLongClick() Call this view's OnLongClickListener, if it is defined.
void	playSoundEffect(int soundConstant) Play a sound effect for this view.
boolean	post(Runnable action) Causes the Runnable to be added to the message queue.
boolean	postDelayed(Runnable action, long delayMillis) Causes the Runnable to be added to the message queue, to be run after the specified amount of time elapses.
void	postInvalidate(int left, int top, int right, int bottom) Cause an invalidate of the specified area to happen on a subsequent cycle through the event loop.
void	postInvalidate() Cause an invalidate to happen on a subsequent cycle through the event loop.
void	postInvalidateDelayed(long delayMilliseconds, int left, int top, int right, int bottom) Cause an invalidate of the specified area to happen on a subsequent cycle through the event loop.
void	postInvalidateDelayed(long delayMilliseconds) Cause an invalidate to happen on a subsequent cycle through the event loop.
void	postInvalidateOnAnimation(int left, int top, int right, int bottom) Cause an invalidate of the specified area to happen on the next animation time step, typically the next display frame.
void	postInvalidateOnAnimation() Cause an invalidate to happen on the next animation time step, typically the next display frame.
void	postOnAnimation(Runnable action) Causes the Runnable to execute on the next animation time step.
void	postOnAnimationDelayed(Runnable action, long delayMillis) Causes the Runnable to execute on the next animation time step, after the specified amount of time elapses.
void	refreshDrawableState() Call this to force a view to update its drawable state.
boolean	removeCallbacks(Runnable action) Removes the specified Runnable from the message queue.
void	removeOnAttachStateChangeListener(View.OnAttachStateChangeListener listener) Remove a listener for attach state changes.
void	removeOnLayoutChangeListener(View.OnLayoutChangeListener listener) Remove a listener for layout changes.
void	requestFitSystemWindows() Ask that a new dispatch of `fitSystemWindows(Rect)` be performed.
boolean	requestFocus(int direction, Rect previouslyFocusedRect) Call this to try to give focus to a specific view or to one of its descendants and give it hints about the direction and a specific rectangle that the focus is coming from.
final boolean	requestFocus(int direction) Call this to try to give focus to a specific view or to one of its descendants and give it a hint about what direction focus is heading.
final boolean	requestFocus() Call this to try to give focus to a specific view or to one of its descendants.
final boolean	requestFocusFromTouch() Call this to try to give focus to a specific view or to one of its descendants.
void	requestLayout() Call this when something has changed which has invalidated the layout of this view.
boolean	requestRectangleOnScreen(Rect rectangle) Request that a rectangle of this view be visible on the screen, scrolling if necessary just enough.
boolean	requestRectangleOnScreen(Rect rectangle, boolean immediate) Request that a rectangle of this view be visible on the screen, scrolling if necessary just enough.
static int	resolveSize(int size, int measureSpec) Version of `resolveSizeAndState(int, int, int)` returning only the `MEASURED_SIZE_MASK` bits of the result.
static int	resolveSizeAndState(int size, int measureSpec, int childMeasuredState) Utility to reconcile a desired size and state, with constraints imposed by a MeasureSpec.
void	restoreHierarchyState(SparseArray<Parcelable> container) Restore this view hierarchy's frozen state from the given container.
void	saveHierarchyState(SparseArray<Parcelable> container) Store this view hierarchy's frozen state into the given container.
void	scheduleDrawable(Drawable who, Runnable what, long when) Schedules an action on a drawable to occur at a specified time.
void	scrollBy(int x, int y) Move the scrolled position of your view.
void	scrollTo(int x, int y) Set the scrolled position of your view.
void	sendAccessibilityEvent(int eventType) Sends an accessibility event of the given type.
void	sendAccessibilityEventUnchecked(AccessibilityEvent event) This method behaves exactly as `sendAccessibilityEvent(int)` but takes as an argument an empty `AccessibilityEvent` and does not perform a check whether accessibility is enabled.
void	setAccessibilityDelegate(View.AccessibilityDelegate delegate) Sets a delegate for implementing accessibility support via composition as opposed to inheritance.
void	setAccessibilityLiveRegion(int mode) Sets the live region mode for this view.
void	setActivated(boolean activated) Changes the activated state of this view.
void	setAlpha(float alpha) Sets the opacity of the view.
void	setAnimation(Animation animation) Sets the next animation to play for this view.
void	setBackground(Drawable background) Set the background to a given Drawable, or remove the background.
void	setBackgroundColor(int color) Sets the background color for this view.
void	setBackgroundDrawable(Drawable background) This method was deprecated in API level 16. use `setBackground(Drawable)` instead
void	setBackgroundResource(int resid) Set the background to a given resource.
final void	setBottom(int bottom) Sets the bottom position of this view relative to its parent.
void	setCameraDistance(float distance) Sets the distance along the Z axis (orthogonal to the X/Y plane on which views are drawn) from the camera to this view.
void	setClickable(boolean clickable) Enables or disables click events for this view.
void	setClipBounds(Rect clipBounds) Sets a rectangular area on this view to which the view will be clipped when it is drawn.
void	setContentDescription(CharSequence contentDescription) Sets the `View` description.
void	setDrawingCacheBackgroundColor(int color) Setting a solid background color for the drawing cache's bitmaps will improve performance and memory usage.
void	setDrawingCacheEnabled(boolean enabled) Enables or disables the drawing cache.
void	setDrawingCacheQuality(int quality) Set the drawing cache quality of this view.
void	setDuplicateParentStateEnabled(boolean enabled) Enables or disables the duplication of the parent's state into this view.
void	setEnabled(boolean enabled) Set the enabled state of this view.
void	setFadingEdgeLength(int length) Set the size of the faded edge used to indicate that more content in this view is available.
void	setFilterTouchesWhenObscured(boolean enabled) Sets whether the framework should discard touches when the view's window is obscured by another visible window.
void	setFitsSystemWindows(boolean fitSystemWindows) Sets whether or not this view should account for system screen decorations such as the status bar and inset its content; that is, controlling whether the default implementation of `fitSystemWindows(Rect)` will be executed.
void	setFocusable(boolean focusable) Set whether this view can receive the focus.
void	setFocusableInTouchMode(boolean focusableInTouchMode) Set whether this view can receive focus while in touch mode.
void	setHapticFeedbackEnabled(boolean hapticFeedbackEnabled) Set whether this view should have haptic feedback for events such as long presses.
void	setHasTransientState(boolean hasTransientState) Set whether this view is currently tracking transient state that the framework should attempt to preserve when possible.
void	setHorizontalFadingEdgeEnabled(boolean horizontalFadingEdgeEnabled) Define whether the horizontal edges should be faded when this view is scrolled horizontally.
void	setHorizontalScrollBarEnabled(boolean horizontalScrollBarEnabled) Define whether the horizontal scrollbar should be drawn or not.
void	setHovered(boolean hovered) Sets whether the view is currently hovered.
void	setId(int id) Sets the identifier for this view.
void	setImportantForAccessibility(int mode) Sets how to determine whether this view is important for accessibility which is if it fires accessibility events and if it is reported to accessibility services that query the screen.
void	setKeepScreenOn(boolean keepScreenOn) Controls whether the screen should remain on, modifying the value of `KEEP_SCREEN_ON`.
void	setLabelFor(int id) Sets the id of a view for which this view serves as a label for accessibility purposes.
void	setLayerPaint(Paint paint) Updates the `Paint` object used with the current layer (used only if the current layer type is not set to `LAYER_TYPE_NONE`).
void	setLayerType(int layerType, Paint paint) Specifies the type of layer backing this view.
void	setLayoutDirection(int layoutDirection) Set the layout direction for this view.
void	setLayoutParams(ViewGroup.LayoutParams params) Set the layout parameters associated with this view.
final void	setLeft(int left) Sets the left position of this view relative to its parent.
void	setLongClickable(boolean longClickable) Enables or disables long click events for this view.
final void	setMeasuredDimension(int measuredWidth, int measuredHeight) This method must be called by `onMeasure(int, int)` to store the measured width and measured height.
void	setMinimumHeight(int minHeight) Sets the minimum height of the view.
void	setMinimumWidth(int minWidth) Sets the minimum width of the view.
void	setNextFocusDownId(int nextFocusDownId) Sets the id of the view to use when the next focus is `FOCUS_DOWN`.
void	setNextFocusForwardId(int nextFocusForwardId) Sets the id of the view to use when the next focus is `FOCUS_FORWARD`.
void	setNextFocusLeftId(int nextFocusLeftId) Sets the id of the view to use when the next focus is `FOCUS_LEFT`.
void	setNextFocusRightId(int nextFocusRightId) Sets the id of the view to use when the next focus is `FOCUS_RIGHT`.
void	setNextFocusUpId(int nextFocusUpId) Sets the id of the view to use when the next focus is `FOCUS_UP`.
void	setOnClickListener(View.OnClickListener l) Register a callback to be invoked when this view is clicked.
void	setOnCreateContextMenuListener(View.OnCreateContextMenuListener l) Register a callback to be invoked when the context menu for this view is being built.
void	setOnDragListener(View.OnDragListener l) Register a drag event listener callback object for this View.
void	setOnFocusChangeListener(View.OnFocusChangeListener l) Register a callback to be invoked when focus of this view changed.
void	setOnGenericMotionListener(View.OnGenericMotionListener l) Register a callback to be invoked when a generic motion event is sent to this view.
void	setOnHoverListener(View.OnHoverListener l) Register a callback to be invoked when a hover event is sent to this view.
void	setOnKeyListener(View.OnKeyListener l) Register a callback to be invoked when a hardware key is pressed in this view.
void	setOnLongClickListener(View.OnLongClickListener l) Register a callback to be invoked when this view is clicked and held.
void	setOnSystemUiVisibilityChangeListener(View.OnSystemUiVisibilityChangeListener l) Set a listener to receive callbacks when the visibility of the system bar changes.
void	setOnTouchListener(View.OnTouchListener l) Register a callback to be invoked when a touch event is sent to this view.
void	setOverScrollMode(int overScrollMode) Set the over-scroll mode for this view.
void	setPadding(int left, int top, int right, int bottom) Sets the padding.
void	setPaddingRelative(int start, int top, int end, int bottom) Sets the relative padding.
void	setPivotX(float pivotX) Sets the x location of the point around which the view is `rotated` and `scaled`.
void	setPivotY(float pivotY) Sets the y location of the point around which the view is `rotated` and `scaled`.
void	setPressed(boolean pressed) Sets the pressed state for this view.
final void	setRight(int right) Sets the right position of this view relative to its parent.
void	setRotation(float rotation) Sets the degrees that the view is rotated around the pivot point.
void	setRotationX(float rotationX) Sets the degrees that the view is rotated around the horizontal axis through the pivot point.
void	setRotationY(float rotationY) Sets the degrees that the view is rotated around the vertical axis through the pivot point.
void	setSaveEnabled(boolean enabled) Controls whether the saving of this view's state is enabled (that is, whether its `onSaveInstanceState()` method will be called).
void	setSaveFromParentEnabled(boolean enabled) Controls whether the entire hierarchy under this view will save its state when a state saving traversal occurs from its parent.
void	setScaleX(float scaleX) Sets the amount that the view is scaled in x around the pivot point, as a proportion of the view's unscaled width.
void	setScaleY(float scaleY) Sets the amount that the view is scaled in Y around the pivot point, as a proportion of the view's unscaled width.
void	setScrollBarDefaultDelayBeforeFade(int scrollBarDefaultDelayBeforeFade) Define the delay before scrollbars fade.
void	setScrollBarFadeDuration(int scrollBarFadeDuration) Define the scrollbar fade duration.
void	setScrollBarSize(int scrollBarSize) Define the scrollbar size.
void	setScrollBarStyle(int style) Specify the style of the scrollbars.
void	setScrollContainer(boolean isScrollContainer) Change whether this view is one of the set of scrollable containers in its window.
void	setScrollX(int value) Set the horizontal scrolled position of your view.
void	setScrollY(int value) Set the vertical scrolled position of your view.
void	setScrollbarFadingEnabled(boolean fadeScrollbars) Define whether scrollbars will fade when the view is not scrolling.
void	setSelected(boolean selected) Changes the selection state of this view.
void	setSoundEffectsEnabled(boolean soundEffectsEnabled) Set whether this view should have sound effects enabled for events such as clicking and touching.
void	setSystemUiVisibility(int visibility) Request that the visibility of the status bar or other screen/window decorations be changed.
void	setTag(int key, Object tag) Sets a tag associated with this view and a key.
void	setTag(Object tag) Sets the tag associated with this view.
void	setTextAlignment(int textAlignment) Set the text alignment.
void	setTextDirection(int textDirection) Set the text direction.
final void	setTop(int top) Sets the top position of this view relative to its parent.
void	setTouchDelegate(TouchDelegate delegate) Sets the TouchDelegate for this View.
void	setTranslationX(float translationX) Sets the horizontal location of this view relative to its `left` position.
void	setTranslationY(float translationY) Sets the vertical location of this view relative to its `top` position.
void	setVerticalFadingEdgeEnabled(boolean verticalFadingEdgeEnabled) Define whether the vertical edges should be faded when this view is scrolled vertically.
void	setVerticalScrollBarEnabled(boolean verticalScrollBarEnabled) Define whether the vertical scrollbar should be drawn or not.
void	setVerticalScrollbarPosition(int position) Set the position of the vertical scroll bar.
void	setVisibility(int visibility) Set the enabled state of this view.
void	setWillNotCacheDrawing(boolean willNotCacheDrawing) When a View's drawing cache is enabled, drawing is redirected to an offscreen bitmap.
void	setWillNotDraw(boolean willNotDraw) If this view doesn't do any drawing on its own, set this flag to allow further optimizations.
void	setX(float x) Sets the visual x position of this view, in pixels.
void	setY(float y) Sets the visual y position of this view, in pixels.
boolean	showContextMenu() Bring up the context menu for this view.
ActionMode	startActionMode(ActionMode.Callback callback) Start an action mode.
void	startAnimation(Animation animation) Start the specified animation now.
final boolean	startDrag(ClipData data, View.DragShadowBuilder shadowBuilder, Object myLocalState, int flags) Starts a drag and drop operation.
String	toString() Returns a string containing a concise, human-readable description of this object.
void	unscheduleDrawable(Drawable who) Unschedule any events associated with the given Drawable.
void	unscheduleDrawable(Drawable who, Runnable what) Cancels a scheduled action on a drawable.
boolean	verifyDrawable(Drawable who) If your view subclass is displaying its own Drawable objects, it should override this function and return true for any Drawable it is displaying.
boolean	willNotCacheDrawing() Returns whether or not this View can cache its drawing or not.
boolean	willNotDraw() Returns whether or not this View draws on its own.

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of `Class` that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

From interface android.graphics.drawable.Drawable.Callback

From interface android.view.KeyEvent.Callback

From interface android.view.ViewManager

From interface android.view.ViewParent

abstract void	bringChildToFront(View child) Change the z order of the child so it's on top of all other children.
abstract boolean	canResolveLayoutDirection() Tells if this view parent can resolve the layout direction.
abstract boolean	canResolveTextAlignment() Tells if this view parent can resolve the text alignment.
abstract boolean	canResolveTextDirection() Tells if this view parent can resolve the text direction.
abstract void	childDrawableStateChanged(View child) This method is called on the parent when a child's drawable state has changed.
abstract void	childHasTransientStateChanged(View child, boolean hasTransientState) Called when a child view now has or no longer is tracking transient state.
abstract void	clearChildFocus(View child) Called when a child of this parent is giving up focus
abstract void	createContextMenu(ContextMenu menu) Have the parent populate the specified context menu if it has anything to add (and then recurse on its parent).
abstract View	focusSearch(View v, int direction) Find the nearest view in the specified direction that wants to take focus
abstract void	focusableViewAvailable(View v) Tells the parent that a new focusable view has become available.
abstract boolean	getChildVisibleRect(View child, Rect r, Point offset) Compute the visible part of a rectangular region defined in terms of a child view's coordinates.
abstract int	getLayoutDirection() Return this view parent layout direction.
abstract ViewParent	getParent() Returns the parent if it exists, or null.
abstract ViewParent	getParentForAccessibility() Gets the parent of a given View for accessibility.
abstract int	getTextAlignment() Return this view parent text alignment.
abstract int	getTextDirection() Return this view parent text direction.
abstract void	invalidateChild(View child, Rect r) All or part of a child is dirty and needs to be redrawn.
abstract ViewParent	invalidateChildInParent(int[] location, Rect r) All or part of a child is dirty and needs to be redrawn.
abstract boolean	isLayoutDirectionResolved() Tells if this view parent layout direction is resolved.
abstract boolean	isLayoutRequested() Indicates whether layout was requested on this view parent.
abstract boolean	isTextAlignmentResolved() Tells if this view parent text alignment is resolved.
abstract boolean	isTextDirectionResolved() Tells if this view parent text direction is resolved.
abstract void	notifySubtreeAccessibilityStateChanged(View child, View source, int changeType) Notifies a view parent that the accessibility state of one of its descendants has changed and that the structure of the subtree is different.
abstract void	recomputeViewAttributes(View child) Tell view hierarchy that the global view attributes need to be re-evaluated.
abstract void	requestChildFocus(View child, View focused) Called when a child of this parent wants focus
abstract boolean	requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) Called when a child of this group wants a particular rectangle to be positioned onto the screen.
abstract void	requestDisallowInterceptTouchEvent(boolean disallowIntercept) Called when a child does not want this parent and its ancestors to intercept touch events with `onInterceptTouchEvent(MotionEvent)`.
abstract void	requestFitSystemWindows() Ask that a new dispatch of `View.fitSystemWindows(Rect)` be performed.
abstract void	requestLayout() Called when something has changed which has invalidated the layout of a child of this view parent.
abstract boolean	requestSendAccessibilityEvent(View child, AccessibilityEvent event) Called by a child to request from its parent to send an `AccessibilityEvent`.
abstract void	requestTransparentRegion(View child) Called when a child wants the view hierarchy to gather and report transparent regions to the window compositor.
abstract boolean	showContextMenuForChild(View originalView) Bring up a context menu for the specified view or its ancestors.
abstract ActionMode	startActionModeForChild(View originalView, ActionMode.Callback callback) Start an action mode for the specified view.

From interface android.view.accessibility.AccessibilityEventSource

XML Attributes

android:addStatesFromChildren

Sets whether this ViewGroup's drawable states also include its children's drawable states. This is used, for example, to make a group appear to be focused when its child EditText or button is focused.

Must be a boolean value, either "true" or "false".

This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

This corresponds to the global attribute resource symbol addStatesFromChildren.

Related Methods

android:alwaysDrawnWithCache

Defines whether the ViewGroup should always draw its children using their drawing cache or not. The default value is true.

Must be a boolean value, either "true" or "false".

This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

This corresponds to the global attribute resource symbol alwaysDrawnWithCache.

Related Methods

android:animateLayoutChanges

Defines whether changes in layout (caused by adding and removing items) should cause a LayoutTransition to run. When this flag is set to true, a default LayoutTransition object will be set on the ViewGroup container and default animations will run when these layout changes occur.

Must be a boolean value, either "true" or "false".

This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

This corresponds to the global attribute resource symbol animateLayoutChanges.

Related Methods

setLayoutTransition(LayoutTransition)

android:animationCache

Defines whether layout animations should create a drawing cache for their children. Enabling the animation cache consumes more memory and requires a longer initialization but provides better performance. The animation cache is enabled by default.

Must be a boolean value, either "true" or "false".

This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

This corresponds to the global attribute resource symbol animationCache.

Related Methods

android:clipChildren

Defines whether a child is limited to draw inside of its bounds or not. This is useful with animations that scale the size of the children to more than 100% for instance. In such a case, this property should be set to false to allow the children to draw outside of their bounds. The default value of this property is true.

Must be a boolean value, either "true" or "false".

This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

This corresponds to the global attribute resource symbol clipChildren.

Related Methods

setClipChildren(boolean)

android:clipToPadding

Defines whether the ViewGroup will clip its drawing surface so as to exclude the padding area. This property is set to true by default.

Must be a boolean value, either "true" or "false".

This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

This corresponds to the global attribute resource symbol clipToPadding.

Related Methods

setClipToPadding(boolean)

android:descendantFocusability

Defines the relationship between the ViewGroup and its descendants when looking for a View to take focus.

Must be one of the following constant values.

Constant	Value	Description
`beforeDescendants`	0	The ViewGroup will get focus before any of its descendants.
`afterDescendants`	1	The ViewGroup will get focus only if none of its descendants want it.
`blocksDescendants`	2	The ViewGroup will block its descendants from receiving focus.

This corresponds to the global attribute resource symbol descendantFocusability.

Related Methods

android:layoutAnimation

Defines the layout animation to use the first time the ViewGroup is laid out. Layout animations can also be started manually after the first layout.

Must be a reference to another resource, in the form "@[+][package:]type:name" or to a theme attribute in the form "?[package:][type:]name".

This corresponds to the global attribute resource symbol layoutAnimation.

Related Methods

android:layoutMode

Defines the layout mode of this ViewGroup.

Must be one of the following constant values.

Constant	Value	Description
`clipBounds`	0	Use the children's clip bounds when laying out this container.
`opticalBounds`	1	Use the children's optical bounds when laying out this container.

This corresponds to the global attribute resource symbol layoutMode.

Related Methods

setLayoutMode(int)

android:persistentDrawingCache

Defines the persistence of the drawing cache. The drawing cache might be enabled by a ViewGroup for all its children in specific situations (for instance during a scrolling.) This property lets you persist the cache in memory after its initial usage. Persisting the cache consumes more memory but may prevent frequent garbage collection is the cache is created over and over again. By default the persistence is set to scrolling.

Must be one or more (separated by '|') of the following constant values.

Constant	Value	Description
`none`	0x0	The drawing cache is not persisted after use.
`animation`	0x1	The drawing cache is persisted after a layout animation.
`scrolling`	0x2	The drawing cache is persisted after a scroll.
`all`	0x3	The drawing cache is always persisted.

This corresponds to the global attribute resource symbol persistentDrawingCache.

Related Methods

android:splitMotionEvents

Sets whether this ViewGroup should split MotionEvents to separate child views during touch event dispatch. If false (default), touch events will be dispatched to the child view where the first pointer went down until the last pointer goes up. If true, touch events may be dispatched to multiple children. MotionEvents for each pointer will be dispatched to the child view where the initial ACTION_DOWN event happened. See setMotionEventSplittingEnabled(boolean) for more information.

Must be a boolean value, either "true" or "false".

This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

This corresponds to the global attribute resource symbol splitMotionEvents.

Related Methods

setMotionEventSplittingEnabled(boolean)

Constants

protected static final int CLIP_TO_PADDING_MASK

Added in API level 1

We clip to padding when FLAG_CLIP_TO_PADDING and FLAG_PADDING_NOT_NULL are set at the same time.

Constant Value: 34 (0x00000022)

public static final int FOCUS_AFTER_DESCENDANTS

Added in API level 1

This view will get focus only if none of its descendants want it.

Constant Value: 262144 (0x00040000)

public static final int FOCUS_BEFORE_DESCENDANTS

Added in API level 1

This view will get focus before any of its descendants.

Constant Value: 131072 (0x00020000)

public static final int FOCUS_BLOCK_DESCENDANTS

Added in API level 1

This view will block any of its descendants from getting focus, even if they are focusable.

Constant Value: 393216 (0x00060000)

public static final int LAYOUT_MODE_CLIP_BOUNDS

Added in API level 18

This constant is a layoutMode. Clip bounds are the raw values of left, top, right and bottom.

Constant Value: 0 (0x00000000)

public static final int LAYOUT_MODE_OPTICAL_BOUNDS

Added in API level 18

This constant is a layoutMode. Optical bounds describe where a widget appears to be. They sit inside the clip bounds which need to cover a larger area to allow other effects, such as shadows and glows, to be drawn.

Constant Value: 1 (0x00000001)

public static final int PERSISTENT_ALL_CACHES

Added in API level 1

Used to indicate that all drawing caches should be kept in memory.

Constant Value: 3 (0x00000003)

public static final int PERSISTENT_ANIMATION_CACHE

Added in API level 1

Used to indicate that the animation drawing cache should be kept in memory.

Constant Value: 1 (0x00000001)

public static final int PERSISTENT_NO_CACHE

Added in API level 1

Used to indicate that no drawing cache should be kept in memory.

Constant Value: 0 (0x00000000)

public static final int PERSISTENT_SCROLLING_CACHE

Added in API level 1

Used to indicate that the scrolling drawing cache should be kept in memory.

Constant Value: 2 (0x00000002)

Public Constructors

public ViewGroup (Context context)

Added in API level 1

public ViewGroup (Context context, AttributeSet attrs)

Added in API level 1

public ViewGroup (Context context, AttributeSet attrs, int defStyle)

Added in API level 1

Public Methods

public void addChildrenForAccessibility (ArrayList<View> childrenForAccessibility)

Added in API level 16

Adds the children of a given View for accessibility. Since some Views are not important for accessibility the children for accessibility are not necessarily direct children of the view, rather they are the first level of descendants important for accessibility.

Parameters

childrenForAccessibility	The list of children for accessibility.

public void addFocusables (ArrayList<View> views, int direction, int focusableMode)

Added in API level 4

Adds any focusable views that are descendants of this view (possibly including this view if it is focusable itself) to views. This method adds all focusable views regardless if we are in touch mode or only views focusable in touch mode if we are in touch mode or only views that can take accessibility focus if accessibility is enabeld depending on the focusable mode paramater.

Parameters

views	Focusable views found so far or null if all we are interested is the number of focusables.
direction	The direction of the focus.
focusableMode	The type of focusables to be added.

public boolean addStatesFromChildren ()

Added in API level 1

Returns whether this ViewGroup's drawable states also include its children's drawable states. This is used, for example, to make a group appear to be focused when its child EditText or button is focused.

public void addTouchables (ArrayList<View> views)

Added in API level 1

Add any touchable views that are descendants of this view (possibly including this view if it is touchable itself) to views.

Parameters

views	Touchable views found so far

public void addView (View child, int index, ViewGroup.LayoutParams params)

Added in API level 1

Adds a child view with the specified layout parameters.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

child	the child view to add
index	the position at which to add the child
params	the layout parameters to set on the child

public void addView (View child, ViewGroup.LayoutParams params)

Added in API level 1

Adds a child view with the specified layout parameters.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

child	the child view to add
params	the layout parameters to set on the child

public void addView (View child, int index)

Added in API level 1

Adds a child view. If no layout parameters are already set on the child, the default parameters for this ViewGroup are set on the child.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

child	the child view to add
index	the position at which to add the child

public void addView (View child)

Added in API level 1

Adds a child view. If no layout parameters are already set on the child, the default parameters for this ViewGroup are set on the child.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

child	the child view to add

public void addView (View child, int width, int height)

Added in API level 1

Adds a child view with this ViewGroup's default layout parameters and the specified width and height.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

child	the child view to add

public void bringChildToFront (View child)

Added in API level 1

Change the z order of the child so it's on top of all other children. This ordering change may affect layout, if this container uses an order-dependent layout scheme (e.g., LinearLayout). Prior to KITKAT this method should be followed by calls to requestLayout() and invalidate() on this parent to force the parent to redraw with the new child ordering.

Parameters

child	The child to bring to the top of the z order

public void childDrawableStateChanged (View child)

Added in API level 1

If addStatesFromChildren() is true, refreshes this group's drawable state (to include the states from its children).

Parameters

child	The child whose drawable state has changed.

public void childHasTransientStateChanged (View child, boolean childHasTransientState)

Added in API level 19

Called when a child view has changed whether or not it is tracking transient state.

Parameters

child	Child view whose state has changed
childHasTransientState	true if this child has transient state

public void clearChildFocus (View child)

Added in API level 1

Called when a child of this parent is giving up focus

Parameters

child	The view that is giving up focus

public void clearDisappearingChildren ()

Added in API level 1

Removes any pending animations for views that have been removed. Call this if you don't want animations for exiting views to stack up.

public void clearFocus ()

Added in API level 1

Called when this view wants to give up focus. If focus is cleared onFocusChanged(boolean, int, android.graphics.Rect) is called.

Note: When a View clears focus the framework is trying to give focus to the first focusable View from the top. Hence, if this View is the first from the top that can take focus, then all callbacks related to clearing focus will be invoked after wich the framework will give focus to this view.

public void dispatchConfigurationChanged (Configuration newConfig)

Added in API level 8

Dispatch a notification about a resource configuration change down the view hierarchy. ViewGroups should override to route to their children.

Parameters

newConfig	The new resource configuration.

public void dispatchDisplayHint (int hint)

Added in API level 8

Dispatch a hint about whether this view is displayed. For instance, when a View moves out of the screen, it might receives a display hint indicating the view is not displayed. Applications should not rely on this hint as there is no guarantee that they will receive one.

Parameters

hint	A hint about whether or not this view is displayed: `VISIBLE` or `INVISIBLE`.

public boolean dispatchDragEvent (DragEvent event)

Added in API level 11

Detects if this View is enabled and has a drag event listener. If both are true, then it calls the drag event listener with the DragEvent it received. If the drag event listener returns true, then dispatchDragEvent() returns true.

For all other cases, the method calls the onDragEvent() drag event handler method and returns its result.

This ensures that a drag event is always consumed, even if the View does not have a drag event listener. However, if the View has a listener and the listener returns true, then onDragEvent() is not called.

public boolean dispatchKeyEvent (KeyEvent event)

Added in API level 1

Dispatch a key event to the next view on the focus path. This path runs from the top of the view tree down to the currently focused view. If this view has focus, it will dispatch to itself. Otherwise it will dispatch the next node down the focus path. This method also fires any key listeners.

Parameters

event	The key event to be dispatched.

Returns

True if the event was handled, false otherwise.

public boolean dispatchKeyEventPreIme (KeyEvent event)

Added in API level 3

Dispatch a key event before it is processed by any input method associated with the view hierarchy. This can be used to intercept key events in special situations before the IME consumes them; a typical example would be handling the BACK key to update the application's UI instead of allowing the IME to see it and close itself.

Parameters

event	The key event to be dispatched.

Returns

True if the event was handled, false otherwise.

public boolean dispatchKeyShortcutEvent (KeyEvent event)

Added in API level 1

Dispatches a key shortcut event.

Parameters

event	The key event to be dispatched.

Returns

True if the event was handled by the view, false otherwise.

public void dispatchSetActivated (boolean activated)

Added in API level 11

Dispatch setActivated to all of this View's children.

Parameters

activated	The new activated state

public void dispatchSetSelected (boolean selected)

Added in API level 1

Dispatch setSelected to all of this View's children.

Parameters

selected	The new selected state

public void dispatchSystemUiVisibilityChanged (int visible)

Added in API level 11

Dispatch callbacks to setOnSystemUiVisibilityChangeListener(View.OnSystemUiVisibilityChangeListener) down the view hierarchy.

public boolean dispatchTouchEvent (MotionEvent ev)

Added in API level 1

Pass the touch screen motion event down to the target view, or this view if it is the target.

Parameters

ev	The motion event to be dispatched.

Returns

True if the event was handled by the view, false otherwise.

public boolean dispatchTrackballEvent (MotionEvent event)

Added in API level 1

Pass a trackball motion event down to the focused view.

Parameters

event	The motion event to be dispatched.

Returns

True if the event was handled by the view, false otherwise.

public boolean dispatchUnhandledMove (View focused, int direction)

Added in API level 1

This method is the last chance for the focused view and its ancestors to respond to an arrow key. This is called when the focused view did not consume the key internally, nor could the view system find a new view in the requested direction to give focus to.

Parameters

focused	The currently focused view.
direction	The direction focus wants to move. One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT.

Returns

True if the this view consumed this unhandled move.

public void dispatchWindowFocusChanged (boolean hasFocus)

Added in API level 1

Called when the window containing this view gains or loses window focus. ViewGroups should override to route to their children.

Parameters

hasFocus	True if the window containing this view now has focus, false otherwise.

public void dispatchWindowSystemUiVisiblityChanged (int visible)

Added in API level 16

Dispatch callbacks to onWindowSystemUiVisibilityChanged(int) down the view hierarchy.

public void dispatchWindowVisibilityChanged (int visibility)

Added in API level 1

Dispatch a window visibility change down the view hierarchy. ViewGroups should override to route to their children.

Parameters

visibility	The new visibility of the window.

public void endViewTransition (View view)

Added in API level 11

This method should always be called following an earlier call to startViewTransition(View). The given View is finally removed from its parent and will no longer be displayed. Note that this method does not perform the functionality of removing a view from its parent; it just discontinues the display of a View that has previously been removed.

Returns

view The View object that has been removed but is being kept around in the visible hierarchy by an earlier call to startViewTransition(View).

public View findFocus ()

Added in API level 1

Find the view in the hierarchy rooted at this view that currently has focus.

Returns

The view that currently has focus, or null if no focused view can be found.

public void findViewsWithText (ArrayList<View> outViews, CharSequence text, int flags)

Added in API level 14

Finds the Views that contain given text. The containment is case insensitive. The search is performed by either the text that the View renders or the content description that describes the view for accessibility purposes and the view does not render or both. Clients can specify how the search is to be performed via passing the FIND_VIEWS_WITH_TEXT and FIND_VIEWS_WITH_CONTENT_DESCRIPTION flags.

Parameters

outViews	The output list of matching Views.
text	The text to match against.

public View focusSearch (View focused, int direction)

Added in API level 1

Find the nearest view in the specified direction that wants to take focus.

Parameters

focused	The view that currently has focus
direction	One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT, or 0 for not applicable.

public void focusableViewAvailable (View v)

Added in API level 1

Tells the parent that a new focusable view has become available. This is to handle transitions from the case where there are no focusable views to the case where the first focusable view appears.

Parameters

v	The view that has become newly focusable

public boolean gatherTransparentRegion (Region region)

Added in API level 1

This is used by the RootView to perform an optimization when the view hierarchy contains one or several SurfaceView. SurfaceView is always considered transparent, but its children are not, therefore all View objects remove themselves from the global transparent region (passed as a parameter to this function).

Parameters

region	The transparent region for this ViewAncestor (window).

Returns

Returns true if the effective visibility of the view at this point is opaque, regardless of the transparent region; returns false if it is possible for underlying windows to be seen behind the view.

public ViewGroup.LayoutParams generateLayoutParams (AttributeSet attrs)

Added in API level 1

Returns a new set of layout parameters based on the supplied attributes set.

Parameters

attrs	the attributes to build the layout parameters from

Returns

an instance of ViewGroup.LayoutParams or one of its descendants

public View getChildAt (int index)

Added in API level 1

Returns the view at the specified position in the group.

Parameters

index	the position at which to get the view from

Returns

the view at the specified position or null if the position does not exist within the group

public int getChildCount ()

Added in API level 1

Returns the number of children in the group.

Returns

a positive integer representing the number of children in the group

public static int getChildMeasureSpec (int spec, int padding, int childDimension)

Added in API level 1

Does the hard part of measureChildren: figuring out the MeasureSpec to pass to a particular child. This method figures out the right MeasureSpec for one dimension (height or width) of one child view. The goal is to combine information from our MeasureSpec with the LayoutParams of the child to get the best possible results. For example, if the this view knows its size (because its MeasureSpec has a mode of EXACTLY), and the child has indicated in its LayoutParams that it wants to be the same size as the parent, the parent should ask the child to layout given an exact size.

Parameters

spec	The requirements for this view
padding	The padding of this view for the current dimension and margins, if applicable
childDimension	How big the child wants to be in the current dimension

Returns

a MeasureSpec integer for the child

public boolean getChildVisibleRect (View child, Rect r, Point offset)

Added in API level 1

Compute the visible part of a rectangular region defined in terms of a child view's coordinates.

Returns the clipped visible part of the rectangle r, defined in the child's local coordinate system. r is modified by this method to contain the result, expressed in the global (root) coordinate system.

The resulting rectangle is always axis aligned. If a rotation is applied to a node in the View hierarchy, the result is the axis-aligned bounding box of the visible rectangle.

Parameters

child	A child View, whose rectangular visible region we want to compute
r	The input rectangle, defined in the child coordinate system. Will be overwritten to contain the resulting visible rectangle, expressed in global (root) coordinates
offset	The input coordinates of a point, defined in the child coordinate system. As with the `r` parameter, this will be overwritten to contain the global (root) coordinates of that point. A `null` value is valid (in case you are not interested in this result)

Returns

true if the resulting rectangle is not empty, false otherwise

public boolean getClipChildren ()

Added in API level 18

Returns whether ths group's children are clipped to their bounds before drawing. The default value is true.

Returns

True if the group's children will be clipped to their bounds, false otherwise.

public int getDescendantFocusability ()

Added in API level 1

Gets the descendant focusability of this view group. The descendant focusability defines the relationship between this view group and its descendants when looking for a view to take focus in requestFocus(int, android.graphics.Rect).

Returns

one of FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS.

public View getFocusedChild ()

Added in API level 1

Returns the focused child of this view, if any. The child may have focus or contain focus.

Returns

the focused child or null.

public LayoutAnimationController getLayoutAnimation ()

Added in API level 1

Returns the layout animation controller used to animate the group's children.

Returns

the current animation controller

public Animation.AnimationListener getLayoutAnimationListener ()

Added in API level 1

Returns the animation listener to which layout animation events are sent.

Returns

an Animation.AnimationListener

public int getLayoutMode ()

Added in API level 18

Returns the basis of alignment during layout operations on this ViewGroup: either LAYOUT_MODE_CLIP_BOUNDS or LAYOUT_MODE_OPTICAL_BOUNDS.

If no layoutMode was explicitly set, either programmatically or in an XML resource, the method returns the layoutMode of the view's parent ViewGroup if such a parent exists, otherwise the method returns a default value of LAYOUT_MODE_CLIP_BOUNDS.

Returns

the layout mode to use during layout operations

public LayoutTransition getLayoutTransition ()

Added in API level 11

Gets the LayoutTransition object for this ViewGroup. If the LayoutTransition object is not null, changes in layout which occur because of children being added to or removed from the ViewGroup will be animated according to the animations defined in that LayoutTransition object. By default, the transition object is null (so layout changes are not animated).

Returns

LayoutTranstion The LayoutTransition object that will animated changes in layout. A value of null means no transition will run on layout changes.

public ViewGroupOverlay getOverlay ()

Added in API level 18

Returns the ViewGroupOverlay for this view group, creating it if it does not yet exist. In addition to ViewOverlay's support for drawables, ViewGroupOverlay allows views to be added to the overlay. These views, like overlay drawables, are visual-only; they do not receive input events and should not be used as anything other than a temporary representation of a view in a parent container, such as might be used by an animation effect.

Note: Overlays do not currently work correctly with SurfaceView or TextureView; contents in overlays for these types of views may not display correctly.

Returns

The ViewGroupOverlay object for this view.

public int getPersistentDrawingCache ()

Added in API level 1

Returns an integer indicating what types of drawing caches are kept in memory.

Returns

one or a combination of PERSISTENT_NO_CACHE, PERSISTENT_ANIMATION_CACHE, PERSISTENT_SCROLLING_CACHE and PERSISTENT_ALL_CACHES

public boolean hasFocus ()

Added in API level 1

Returns true if this view has or contains focus

Returns

true if this view has or contains focus

public boolean hasFocusable ()

Added in API level 1

Returns true if this view is focusable or if it contains a reachable View for which hasFocusable() returns true. A "reachable hasFocusable()" is a View whose parents do not block descendants focus. Only VISIBLE views are considered focusable.

Returns

True if the view is focusable or if the view contains a focusable View, false otherwise.

public boolean hasTransientState ()

Added in API level 16

Indicates whether the view is currently tracking transient state that the app should not need to concern itself with saving and restoring, but that the framework should take special note to preserve when possible.

A view with transient state cannot be trivially rebound from an external data source, such as an adapter binding item views in a list. This may be because the view is performing an animation, tracking user selection of content, or similar.

Returns

true if the view has transient state

public int indexOfChild (View child)

Added in API level 1

Returns the position in the group of the specified child view.

Parameters

child	the view for which to get the position

Returns

a positive integer representing the position of the view in the group, or -1 if the view does not exist in the group

public final void invalidateChild (View child, Rect dirty)

Added in API level 1

Don't call or override this method. It is used for the implementation of the view hierarchy.

Parameters

child	The child which is dirty
dirty	The area within the child that is invalid

public ViewParent invalidateChildInParent (int[] location, Rect dirty)

Added in API level 1

Don't call or override this method. It is used for the implementation of the view hierarchy. This implementation returns null if this ViewGroup does not have a parent, if this ViewGroup is already fully invalidated or if the dirty rectangle does not intersect with this ViewGroup's bounds.

Parameters

location	An array of 2 ints containing the left and top coordinates of the child to invalidate
dirty	The area within the child that is invalid

Returns

the parent of this ViewParent or null

public boolean isAlwaysDrawnWithCacheEnabled ()

Added in API level 1

Indicates whether this ViewGroup will always try to draw its children using their drawing cache. By default this property is enabled.

Returns

true if the animation cache is enabled, false otherwise

public boolean isAnimationCacheEnabled ()

Added in API level 1

Indicates whether the children's drawing cache is used during a layout animation. By default, the drawing cache is enabled but this will prevent nested layout animations from working. To nest animations, you must disable the cache.

Returns

true if the animation cache is enabled, false otherwise

public boolean isMotionEventSplittingEnabled ()

Added in API level 11

Returns true if MotionEvents dispatched to this ViewGroup can be split to multiple children.

Returns

true if MotionEvents dispatched to this ViewGroup can be split to multiple children.

public void jumpDrawablesToCurrentState ()

Added in API level 11

Call Drawable.jumpToCurrentState() on all Drawable objects associated with this view.

public final void layout (int l, int t, int r, int b)

Added in API level 1

Assign a size and position to a view and all of its descendants

This is the second phase of the layout mechanism. (The first is measuring). In this phase, each parent calls layout on all of its children to position them. This is typically done using the child measurements that were stored in the measure pass().

Derived classes should not override this method. Derived classes with children should override onLayout. In that method, they should call layout on each of their children.

Parameters

l	Left position, relative to parent
t	Top position, relative to parent
r	Right position, relative to parent
b	Bottom position, relative to parent

public void notifySubtreeAccessibilityStateChanged (View child, View source, int changeType)

Added in API level 19

Notifies a view parent that the accessibility state of one of its descendants has changed and that the structure of the subtree is different.

Parameters

child	The direct child whose subtree has changed.
source	The descendant view that changed.
changeType	A bit mask of the types of changes that occurred. One or more of: `CONTENT_CHANGE_TYPE_CONTENT_DESCRIPTION` `CONTENT_CHANGE_TYPE_SUBTREE` `CONTENT_CHANGE_TYPE_TEXT` `CONTENT_CHANGE_TYPE_UNDEFINED`

public final void offsetDescendantRectToMyCoords (View descendant, Rect rect)

Added in API level 1

Offset a rectangle that is in a descendant's coordinate space into our coordinate space.

Parameters

descendant	A descendant of this view
rect	A rectangle defined in descendant's coordinate space.

public final void offsetRectIntoDescendantCoords (View descendant, Rect rect)

Added in API level 1

Offset a rectangle that is in our coordinate space into an ancestor's coordinate space.

Parameters

descendant	A descendant of this view
rect	A rectangle defined in descendant's coordinate space.

public boolean onInterceptHoverEvent (MotionEvent event)

Added in API level 14

Implement this method to intercept hover events before they are handled by child views.

This method is called before dispatching a hover event to a child of the view group or to the view group's own onHoverEvent(MotionEvent) to allow the view group a chance to intercept the hover event. This method can also be used to watch all pointer motions that occur within the bounds of the view group even when the pointer is hovering over a child of the view group rather than over the view group itself.

The view group can prevent its children from receiving hover events by implementing this method and returning true to indicate that it would like to intercept hover events. The view group must continuously return true from onInterceptHoverEvent(MotionEvent) for as long as it wishes to continue intercepting hover events from its children.

Interception preserves the invariant that at most one view can be hovered at a time by transferring hover focus from the currently hovered child to the view group or vice-versa as needed.

If this method returns true and a child is already hovered, then the child view will first receive a hover exit event and then the view group itself will receive a hover enter event in onHoverEvent(MotionEvent). Likewise, if this method had previously returned true to intercept hover events and instead returns false while the pointer is hovering within the bounds of one of a child, then the view group will first receive a hover exit event in onHoverEvent(MotionEvent) and then the hovered child will receive a hover enter event.

The default implementation always returns false.

Parameters

event	The motion event that describes the hover.

Returns

True if the view group would like to intercept the hover event and prevent its children from receiving it.

public boolean onInterceptTouchEvent (MotionEvent ev)

Added in API level 1

Implement this method to intercept all touch screen motion events. This allows you to watch events as they are dispatched to your children, and take ownership of the current gesture at any point.

Using this function takes some care, as it has a fairly complicated interaction with View.onTouchEvent(MotionEvent), and using it requires implementing that method as well as this one in the correct way. Events will be received in the following order:

You will receive the down event here.
The down event will be handled either by a child of this view group, or given to your own onTouchEvent() method to handle; this means you should implement onTouchEvent() to return true, so you will continue to see the rest of the gesture (instead of looking for a parent view to handle it). Also, by returning true from onTouchEvent(), you will not receive any following events in onInterceptTouchEvent() and all touch processing must happen in onTouchEvent() like normal.
For as long as you return false from this function, each following event (up to and including the final up) will be delivered first here and then to the target's onTouchEvent().
If you return true from here, you will not receive any following events: the target view will receive the same event but with the action ACTION_CANCEL, and all further events will be delivered to your onTouchEvent() method and no longer appear here.

Parameters

ev	The motion event being dispatched down the hierarchy.

Returns

Return true to steal motion events from the children and have them dispatched to this ViewGroup through onTouchEvent(). The current target will receive an ACTION_CANCEL event, and no further messages will be delivered here.

public boolean onRequestSendAccessibilityEvent (View child, AccessibilityEvent event)

Added in API level 14

Called when a child has requested sending an AccessibilityEvent and gives an opportunity to its parent to augment the event.

If an View.AccessibilityDelegate has been specified via calling setAccessibilityDelegate(android.view.View.AccessibilityDelegate) its onRequestSendAccessibilityEvent(ViewGroup, View, AccessibilityEvent) is responsible for handling this call.

Parameters

child	The child which requests sending the event.
event	The event to be sent.

Returns

True if the event should be sent.

public void recomputeViewAttributes (View child)

Added in API level 1

Tell view hierarchy that the global view attributes need to be re-evaluated.

Parameters

child	View whose attributes have changed.

public void removeAllViews ()

Added in API level 1

Call this method to remove all child views from the ViewGroup.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

public void removeAllViewsInLayout ()

Added in API level 1

Called by a ViewGroup subclass to remove child views from itself, when it must first know its size on screen before it can calculate how many child views it will render. An example is a Gallery or a ListView, which may "have" 50 children, but actually only render the number of children that can currently fit inside the object on screen. Do not call this method unless you are extending ViewGroup and understand the view measuring and layout pipeline.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

public void removeView (View view)

Added in API level 1

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

public void removeViewAt (int index)

Added in API level 1

Removes the view at the specified position in the group.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

index	the position in the group of the view to remove

public void removeViewInLayout (View view)

Added in API level 1

Removes a view during layout. This is useful if in your onLayout() method, you need to remove more views.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

view	the view to remove from the group

public void removeViews (int start, int count)

Added in API level 1

Removes the specified range of views from the group.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

start	the first position in the group of the range of views to remove
count	the number of views to remove

public void removeViewsInLayout (int start, int count)

Added in API level 1

Removes a range of views during layout. This is useful if in your onLayout() method, you need to remove more views.

Note: do not invoke this method from draw(android.graphics.Canvas), onDraw(android.graphics.Canvas), dispatchDraw(android.graphics.Canvas) or any related method.

Parameters

start	the index of the first view to remove from the group
count	the number of views to remove from the group

public void requestChildFocus (View child, View focused)

Added in API level 1

Called when a child of this parent wants focus

Parameters

child	The child of this ViewParent that wants focus. This view will contain the focused view. It is not necessarily the view that actually has focus.
focused	The view that is a descendant of child that actually has focus

public boolean requestChildRectangleOnScreen (View child, Rect rectangle, boolean immediate)

Added in API level 1

Called when a child of this group wants a particular rectangle to be positioned onto the screen. ViewGroups overriding this can trust that:

child will be a direct child of this group
rectangle will be in the child's coordinates

ViewGroups overriding this should uphold the contract:

nothing will change if the rectangle is already visible
the view port will be scrolled only just enough to make the rectangle visible

Parameters

child	The direct child making the request.
rectangle	The rectangle in the child's coordinates the child wishes to be on the screen.
immediate	True to forbid animated or delayed scrolling, false otherwise

Returns

Whether the group scrolled to handle the operation

public void requestDisallowInterceptTouchEvent (boolean disallowIntercept)

Added in API level 1

Called when a child does not want this parent and its ancestors to intercept touch events with onInterceptTouchEvent(MotionEvent).

This parent should pass this call onto its parents. This parent must obey this request for the duration of the touch (that is, only clear the flag after this parent has received an up or a cancel.

Parameters

disallowIntercept	True if the child does not want the parent to intercept touch events.

public boolean requestFocus (int direction, Rect previouslyFocusedRect)

Added in API level 1

Call this to try to give focus to a specific view or to one of its descendants and give it hints about the direction and a specific rectangle that the focus is coming from. The rectangle can help give larger views a finer grained hint about where focus is coming from, and therefore, where to show selection, or forward focus change internally. A view will not actually take focus if it is not focusable (isFocusable() returns false), or if it is focusable and it is not focusable in touch mode (isFocusableInTouchMode()) while the device is in touch mode. A View will not take focus if it is not visible. A View will not take focus if one of its parents has getDescendantFocusability() equal to FOCUS_BLOCK_DESCENDANTS. See also focusSearch(int), which is what you call to say that you have focus, and you want your parent to look for the next one. You may wish to override this method if your custom View has an internal View that it wishes to forward the request to. Looks for a view to give focus to respecting the setting specified by getDescendantFocusability(). Uses onRequestFocusInDescendants(int, android.graphics.Rect) to find focus within the children of this group when appropriate.

Parameters

direction	One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT
previouslyFocusedRect	The rectangle (in this View's coordinate system) to give a finer grained hint about where focus is coming from. May be null if there is no hint.

Returns

Whether this view or one of its descendants actually took focus.

public boolean requestSendAccessibilityEvent (View child, AccessibilityEvent event)

Added in API level 14

Called by a child to request from its parent to send an AccessibilityEvent. The child has already populated a record for itself in the event and is delegating to its parent to send the event. The parent can optionally add a record for itself.

Note: An accessibility event is fired by an individual view which populates the event with a record for its state and requests from its parent to perform the sending. The parent can optionally add a record for itself before dispatching the request to its parent. A parent can also choose not to respect the request for sending the event. The accessibility event is sent by the topmost view in the view tree.

Parameters

child	The child which requests sending the event.
event	The event to be sent.

Returns

True if the event was sent.

public void requestTransparentRegion (View child)

Added in API level 1

Called when a child wants the view hierarchy to gather and report transparent regions to the window compositor. Views that "punch" holes in the view hierarchy, such as SurfaceView can use this API to improve performance of the system. When no such a view is present in the hierarchy, this optimization in unnecessary and might slightly reduce the view hierarchy performance.

Parameters

child	the view requesting the transparent region computation

public void scheduleLayoutAnimation ()

Added in API level 1

Schedules the layout animation to be played after the next layout pass of this view group. This can be used to restart the layout animation when the content of the view group changes or when the activity is paused and resumed.

public void setAddStatesFromChildren (boolean addsStates)

Added in API level 1

public void setAlwaysDrawnWithCacheEnabled (boolean always)

Added in API level 1

Indicates whether this ViewGroup will always try to draw its children using their drawing cache. This property can be set to true when the cache rendering is slightly different from the children's normal rendering. Renderings can be different, for instance, when the cache's quality is set to low. When this property is disabled, the ViewGroup will use the drawing cache of its children only when asked to. It's usually the task of subclasses to tell ViewGroup when to start using the drawing cache and when to stop using it.

Parameters

always	true to always draw with the drawing cache, false otherwise

public void setAnimationCacheEnabled (boolean enabled)

Added in API level 1

Enables or disables the children's drawing cache during a layout animation. By default, the drawing cache is enabled but this will prevent nested layout animations from working. To nest animations, you must disable the cache.

Parameters

enabled	true to enable the animation cache, false otherwise

public void setClipChildren (boolean clipChildren)

Added in API level 1

By default, children are clipped to their bounds before drawing. This allows view groups to override this behavior for animations, etc.

Related XML Attributes

android:clipChildren

Parameters

clipChildren	true to clip children to their bounds, false otherwise

public void setClipToPadding (boolean clipToPadding)

Added in API level 1

By default, children are clipped to the padding of the ViewGroup. This allows view groups to override this behavior

Related XML Attributes

android:clipToPadding

Parameters

clipToPadding	true to clip children to the padding of the group, false otherwise

public void setDescendantFocusability (int focusability)

Added in API level 1

Set the descendant focusability of this view group. This defines the relationship between this view group and its descendants when looking for a view to take focus in requestFocus(int, android.graphics.Rect).

Parameters

focusability	one of `FOCUS_BEFORE_DESCENDANTS`, `FOCUS_AFTER_DESCENDANTS`, `FOCUS_BLOCK_DESCENDANTS`.

public void setLayoutAnimation (LayoutAnimationController controller)

Added in API level 1

Sets the layout animation controller used to animate the group's children after the first layout.

Parameters

controller	the animation controller

public void setLayoutAnimationListener (Animation.AnimationListener animationListener)

Added in API level 1

Specifies the animation listener to which layout animation events must be sent. Only onAnimationStart(Animation) and onAnimationEnd(Animation) are invoked.

Parameters

animationListener	the layout animation listener

public void setLayoutMode (int layoutMode)

Added in API level 18

Sets the basis of alignment during the layout of this ViewGroup. Valid values are either LAYOUT_MODE_CLIP_BOUNDS or LAYOUT_MODE_OPTICAL_BOUNDS.

Related XML Attributes

android:layoutMode

Parameters

layoutMode	the layout mode to use during layout operations

public void setLayoutTransition (LayoutTransition transition)

Added in API level 11

Sets the LayoutTransition object for this ViewGroup. If the LayoutTransition object is not null, changes in layout which occur because of children being added to or removed from the ViewGroup will be animated according to the animations defined in that LayoutTransition object. By default, the transition object is null (so layout changes are not animated).

Replacing a non-null transition will cause that previous transition to be canceled, if it is currently running, to restore this container to its correct post-transition state.

Related XML Attributes

android:animateLayoutChanges

Parameters

transition	The LayoutTransition object that will animated changes in layout. A value of `null` means no transition will run on layout changes.

public void setMotionEventSplittingEnabled (boolean split)

Added in API level 11

Enable or disable the splitting of MotionEvents to multiple children during touch event dispatch. This behavior is enabled by default for applications that target an SDK version of HONEYCOMB or newer.

When this option is enabled MotionEvents may be split and dispatched to different child views depending on where each pointer initially went down. This allows for user interactions such as scrolling two panes of content independently, chording of buttons, and performing independent gestures on different pieces of content.

Related XML Attributes

android:splitMotionEvents

Parameters

split	`true` to allow MotionEvents to be split and dispatched to multiple child views. `false` to only allow one child view to be the target of any MotionEvent received by this ViewGroup.

public void setOnHierarchyChangeListener (ViewGroup.OnHierarchyChangeListener listener)

Added in API level 1

Parameters

listener	the callback to invoke on hierarchy change

public void setPersistentDrawingCache (int drawingCacheToKeep)

Added in API level 1

Indicates what types of drawing caches should be kept in memory after they have been created.

Parameters

drawingCacheToKeep	one or a combination of `PERSISTENT_NO_CACHE`, `PERSISTENT_ANIMATION_CACHE`, `PERSISTENT_SCROLLING_CACHE` and `PERSISTENT_ALL_CACHES`

public boolean shouldDelayChildPressedState ()

Added in API level 14

Return true if the pressed state should be delayed for children or descendants of this ViewGroup. Generally, this should be done for containers that can scroll, such as a List. This prevents the pressed state from appearing when the user is actually trying to scroll the content. The default implementation returns true for compatibility reasons. Subclasses that do not scroll should generally override this method and return false.

public boolean showContextMenuForChild (View originalView)

Added in API level 1

Bring up a context menu for the specified view or its ancestors.

In most cases, a subclass does not need to override this. However, if the subclass is added directly to the window manager (for example, addView(View, android.view.ViewGroup.LayoutParams)) then it should override this and show the context menu.

Parameters

originalView	The source view where the context menu was first invoked

Returns

true if a context menu was displayed

public ActionMode startActionModeForChild (View originalView, ActionMode.Callback callback)

Added in API level 11

Start an action mode for the specified view.

Parameters

originalView	The source view where the action mode was first invoked
callback	The callback that will handle lifecycle events for the action mode

Returns

The new action mode if it was started, null otherwise

public void startLayoutAnimation ()

Added in API level 1

Runs the layout animation. Calling this method triggers a relayout of this view group.

public void startViewTransition (View view)

Added in API level 11

This method tells the ViewGroup that the given View object, which should have this ViewGroup as its parent, should be kept around (re-displayed when the ViewGroup draws its children) even if it is removed from its parent. This allows animations, such as those used by Fragment and LayoutTransition to animate the removal of views. A call to this method should always be accompanied by a later call to endViewTransition(View), such as after an animation on the View has finished, so that the View finally gets removed.

Parameters

view	The View object to be kept visible even if it gets removed from its parent.

public void updateViewLayout (View view, ViewGroup.LayoutParams params)

Added in API level 1

Protected Methods

protected boolean addViewInLayout (View child, int index, ViewGroup.LayoutParams params, boolean preventRequestLayout)

Added in API level 1

Adds a view during layout. This is useful if in your onLayout() method, you need to add more views (as does the list view for example). If index is negative, it means put it at the end of the list.

Parameters

child	the view to add to the group
index	the index at which the child must be added
params	the layout parameters to associate with the child
preventRequestLayout	if true, calling this method will not trigger a layout request on child

Returns

true if the child was added, false otherwise

protected boolean addViewInLayout (View child, int index, ViewGroup.LayoutParams params)

Added in API level 1

Adds a view during layout. This is useful if in your onLayout() method, you need to add more views (as does the list view for example). If index is negative, it means put it at the end of the list.

Parameters

child	the view to add to the group
index	the index at which the child must be added
params	the layout parameters to associate with the child

Returns

true if the child was added, false otherwise

protected void attachLayoutAnimationParameters (View child, ViewGroup.LayoutParams params, int index, int count)

Added in API level 1

Subclasses should override this method to set layout animation parameters on the supplied child.

Parameters

child	the child to associate with animation parameters
params	the child's layout parameters which hold the animation parameters
index	the index of the child in the view group
count	the number of children in the view group

protected void attachViewToParent (View child, int index, ViewGroup.LayoutParams params)

Added in API level 1

Attaches a view to this view group. Attaching a view assigns this group as the parent, sets the layout parameters and puts the view in the list of children so that it can be retrieved by calling getChildAt(int).

This method is intended to be lightweight and makes no assumptions about whether the parent or child should be redrawn. Proper use of this method will include also making any appropriate requestLayout() or invalidate() calls. For example, callers can post a Runnable which performs a requestLayout() on the next frame, after all detach/attach calls are finished, causing layout to be run prior to redrawing the view hierarchy.

This method should be called only for views which were detached from their parent.

Parameters

child	the child to attach
index	the index at which the child should be attached
params	the layout parameters of the child

protected boolean canAnimate ()

Added in API level 1

Indicates whether the view group has the ability to animate its children after the first layout.

Returns

true if the children can be animated, false otherwise

protected boolean checkLayoutParams (ViewGroup.LayoutParams p)

Added in API level 1

protected void cleanupLayoutState (View child)

Added in API level 1

Prevents the specified child to be laid out during the next layout pass.

Parameters

child	the child on which to perform the cleanup

protected void debug (int depth)

Added in API level 1

Prints information about this view in the log output, with the tag VIEW_LOG_TAG. Each line in the output is preceded with an indentation defined by the depth.

Parameters

depth	the indentation level

protected void detachAllViewsFromParent ()

Added in API level 1

Detaches all views from the parent. Detaching a view should be followed either by a call to attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) or a call to removeDetachedView(View, boolean). Detachment should only be temporary; reattachment or removal should happen within the same drawing cycle as detachment. When a view is detached, its parent is null and cannot be retrieved by a call to getChildAt(int).

protected void detachViewFromParent (View child)

Added in API level 1

Detaches a view from its parent. Detaching a view should be followed either by a call to attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) or a call to removeDetachedView(View, boolean). Detachment should only be temporary; reattachment or removal should happen within the same drawing cycle as detachment. When a view is detached, its parent is null and cannot be retrieved by a call to getChildAt(int).

Parameters

child	the child to detach

protected void detachViewFromParent (int index)

Added in API level 1

Parameters

index	the index of the child to detach

protected void detachViewsFromParent (int start, int count)

Added in API level 1

Detaches a range of views from their parents. Detaching a view should be followed either by a call to attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) or a call to removeDetachedView(View, boolean). Detachment should only be temporary; reattachment or removal should happen within the same drawing cycle as detachment. When a view is detached, its parent is null and cannot be retrieved by a call to getChildAt(int).

Parameters

start	the first index of the childrend range to detach
count	the number of children to detach

protected void dispatchDraw (Canvas canvas)

Added in API level 1

Called by draw to draw the child views. This may be overridden by derived classes to gain control just before its children are drawn (but after its own view has been drawn).

Parameters

canvas	the canvas on which to draw the view

protected void dispatchFreezeSelfOnly (SparseArray<Parcelable> container)

Added in API level 1

Perform dispatching of a saveHierarchyState(android.util.SparseArray) freeze()} to only this view, not to its children. For use when overriding dispatchSaveInstanceState(android.util.SparseArray) dispatchFreeze()} to allow subclasses to freeze their own state but not the state of their children.

Parameters

container	the container

protected boolean dispatchGenericFocusedEvent (MotionEvent event)

Added in API level 14

Dispatch a generic motion event to the currently focused view.

Do not call this method directly. Call dispatchGenericMotionEvent(MotionEvent) instead.

Parameters

event	The motion event to be dispatched.

Returns

True if the event was handled by the view, false otherwise.

protected boolean dispatchGenericPointerEvent (MotionEvent event)

Added in API level 14

Dispatch a generic motion event to the view under the first pointer.

Do not call this method directly. Call dispatchGenericMotionEvent(MotionEvent) instead.

Parameters

event	The motion event to be dispatched.

Returns

True if the event was handled by the view, false otherwise.

protected boolean dispatchHoverEvent (MotionEvent event)

Added in API level 14

Dispatch a hover event.

Do not call this method directly. Call dispatchGenericMotionEvent(MotionEvent) instead.

Parameters

event	The motion event to be dispatched.

Returns

True if the event was handled by the view, false otherwise.

protected void dispatchRestoreInstanceState (SparseArray<Parcelable> container)

Added in API level 1

Called by restoreHierarchyState(android.util.SparseArray) to retrieve the state for this view and its children. May be overridden to modify how restoring happens to a view's children; for example, some views may want to not store state for their children.

Parameters

container	The SparseArray which holds previously saved state.

protected void dispatchSaveInstanceState (SparseArray<Parcelable> container)

Added in API level 1

Called by saveHierarchyState(android.util.SparseArray) to store the state for this view and its children. May be overridden to modify how freezing happens to a view's children; for example, some views may want to not store state for their children.

Parameters

container	The SparseArray in which to save the view's state.

protected void dispatchSetPressed (boolean pressed)

Added in API level 1

Dispatch setPressed to all of this View's children.

Parameters

pressed	The new pressed state

protected void dispatchThawSelfOnly (SparseArray<Parcelable> container)

Added in API level 1

Perform dispatching of a restoreHierarchyState(android.util.SparseArray) to only this view, not to its children. For use when overriding dispatchRestoreInstanceState(android.util.SparseArray) to allow subclasses to thaw their own state but not the state of their children.

Parameters

container	the container

protected void dispatchVisibilityChanged (View changedView, int visibility)

Added in API level 8

Dispatch a view visibility change down the view hierarchy. ViewGroups should override to route to their children.

Parameters

changedView	The view whose visibility changed. Could be 'this' or an ancestor view.
visibility	The new visibility of changedView: `VISIBLE`, `INVISIBLE` or `GONE`.

protected boolean drawChild (Canvas canvas, View child, long drawingTime)

Added in API level 1

Draw one child of this View Group. This method is responsible for getting the canvas in the right state. This includes clipping, translating so that the child's scrolled origin is at 0, 0, and applying any animation transformations.

Parameters

canvas	The canvas on which to draw the child
child	Who to draw
drawingTime	The time at which draw is occurring

Returns

True if an invalidate() was issued

protected void drawableStateChanged ()

Added in API level 1

This function is called whenever the state of the view changes in such a way that it impacts the state of drawables being shown.

Be sure to call through to the superclass when overriding this function.

protected boolean fitSystemWindows (Rect insets)

Added in API level 1

Called by the view hierarchy when the content insets for a window have changed, to allow it to adjust its content to fit within those windows. The content insets tell you the space that the status bar, input method, and other system windows infringe on the application's window.

You do not normally need to deal with this function, since the default window decoration given to applications takes care of applying it to the content of the window. If you use SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN or SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION this will not be the case, and your content can be placed under those system elements. You can then use this method within your view hierarchy if you have parts of your UI which you would like to ensure are not being covered.

The default implementation of this method simply applies the content insets to the view's padding, consuming that content (modifying the insets to be 0), and returning true. This behavior is off by default, but can be enabled through setFitsSystemWindows(boolean).

This function's traversal down the hierarchy is depth-first. The same content insets object is propagated down the hierarchy, so any changes made to it will be seen by all following views (including potentially ones above in the hierarchy since this is a depth-first traversal). The first view that returns true will abort the entire traversal.

The default implementation works well for a situation where it is used with a container that covers the entire window, allowing it to apply the appropriate insets to its content on all edges. If you need a more complicated layout (such as two different views fitting system windows, one on the top of the window, and one on the bottom), you can override the method and handle the insets however you would like. Note that the insets provided by the framework are always relative to the far edges of the window, not accounting for the location of the called view within that window. (In fact when this method is called you do not yet know where the layout will place the view, as it is done before layout happens.)

Note: unlike many View methods, there is no dispatch phase to this call. If you are overriding it in a ViewGroup and want to allow the call to continue to your children, you must be sure to call the super implementation.

Here is a sample layout that makes use of fitting system windows to have controls for a video view placed inside of the window decorations that it hides and shows. This can be used with code like the second sample (video player) shown in setSystemUiVisibility(int).

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="match_parent"
    >
    <view class="com.example.android.apis.view.VideoPlayerActivity$Content"
        android:id="@+id/content"
        android:src="@drawable/frantic"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="center"
        />
    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true"
        android:animateLayoutChanges="true"
        >
        <TextView
            android:id="@+id/title"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="top|center_horizontal"
            android:textColor="#ffffffff"
            android:background="#a0000000"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:gravity="left"
            android:padding="16dp"
            android:text="A title goes here"
            />
        <Button
            android:id="@+id/play"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:gravity="center"
            android:textSize="28dp"
            />
        <SeekBar
            android:id="@+id/seekbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|center_horizontal"
            android:layout_marginBottom="16dp"
            />
    </FrameLayout>
</FrameLayout>

Parameters

insets	Current content insets of the window. Prior to `JELLY_BEAN` you must not modify the insets or else you and Android will be unhappy.

Returns

true if this view applied the insets and it should not continue propagating further down the hierarchy, false otherwise.

protected ViewGroup.LayoutParams generateDefaultLayoutParams ()

Added in API level 1

Returns a set of default layout parameters. These parameters are requested when the View passed to addView(View) has no layout parameters already set. If null is returned, an exception is thrown from addView.

Returns

a set of default layout parameters or null

protected ViewGroup.LayoutParams generateLayoutParams (ViewGroup.LayoutParams p)

Added in API level 1

Returns a safe set of layout parameters based on the supplied layout params. When a ViewGroup is passed a View whose layout params do not pass the test of checkLayoutParams(android.view.ViewGroup.LayoutParams), this method is invoked. This method should return a new set of layout params suitable for this ViewGroup, possibly by copying the appropriate attributes from the specified set of layout params.

Parameters

p	The layout parameters to convert into a suitable set of layout parameters for this ViewGroup.

Returns

an instance of ViewGroup.LayoutParams or one of its descendants

protected int getChildDrawingOrder (int childCount, int i)

Added in API level 1

Returns the index of the child to draw for this iteration. Override this if you want to change the drawing order of children. By default, it returns i.

NOTE: In order for this method to be called, you must enable child ordering first by calling setChildrenDrawingOrderEnabled(boolean).

Parameters

i	The current iteration.

Returns

The index of the child to draw this iteration.

protected boolean getChildStaticTransformation (View child, Transformation t)

Added in API level 1

Sets t to be the static transformation of the child, if set, returning a boolean to indicate whether a static transform was set. The default implementation simply returns false; subclasses may override this method for different behavior. setStaticTransformationsEnabled(boolean) must be set to true for this method to be called.

Parameters

child	The child view whose static transform is being requested
t	The Transformation which will hold the result

Returns

true if the transformation was set, false otherwise

protected boolean isChildrenDrawingOrderEnabled ()

Added in API level 7

Indicates whether the ViewGroup is drawing its children in the order defined by getChildDrawingOrder(int, int).

Returns

true if children drawing order is defined by getChildDrawingOrder(int, int), false otherwise

protected boolean isChildrenDrawnWithCacheEnabled ()

Added in API level 1

Indicates whether the ViewGroup is currently drawing its children using their drawing cache.

Returns

true if children should be drawn with their cache, false otherwise

protected void measureChild (View child, int parentWidthMeasureSpec, int parentHeightMeasureSpec)

Added in API level 1

Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding. The heavy lifting is done in getChildMeasureSpec.

Parameters

child	The child to measure
parentWidthMeasureSpec	The width requirements for this view
parentHeightMeasureSpec	The height requirements for this view

protected void measureChildWithMargins (View child, int parentWidthMeasureSpec, int widthUsed, int parentHeightMeasureSpec, int heightUsed)

Added in API level 1

Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding and margins. The child must have MarginLayoutParams The heavy lifting is done in getChildMeasureSpec.

Parameters

child	The child to measure
parentWidthMeasureSpec	The width requirements for this view
widthUsed	Extra space that has been used up by the parent horizontally (possibly by other children of the parent)
parentHeightMeasureSpec	The height requirements for this view
heightUsed	Extra space that has been used up by the parent vertically (possibly by other children of the parent)

protected void measureChildren (int widthMeasureSpec, int heightMeasureSpec)

Added in API level 1

Ask all of the children of this view to measure themselves, taking into account both the MeasureSpec requirements for this view and its padding. We skip children that are in the GONE state The heavy lifting is done in getChildMeasureSpec.

Parameters

widthMeasureSpec	The width requirements for this view
heightMeasureSpec	The height requirements for this view

protected void onAnimationEnd ()

Added in API level 1

Invoked by a parent ViewGroup to notify the end of the animation currently associated with this view. If you override this method, always call super.onAnimationEnd();

protected void onAnimationStart ()

Added in API level 1

Invoked by a parent ViewGroup to notify the start of the animation currently associated with this view. If you override this method, always call super.onAnimationStart();

protected void onAttachedToWindow ()

Added in API level 1

This is called when the view is attached to a window. At this point it has a Surface and will start drawing. Note that this function is guaranteed to be called before onDraw(android.graphics.Canvas), however it may be called any time before the first onDraw -- including before or after onMeasure(int, int).

protected int[] onCreateDrawableState (int extraSpace)

Added in API level 1

Generate the new Drawable state for this view. This is called by the view system when the cached Drawable state is determined to be invalid. To retrieve the current state, you should use getDrawableState().

Parameters

extraSpace	if non-zero, this is the number of extra entries you would like in the returned array in which you can place your own states.

Returns

Returns an array holding the current Drawable state of the view.

protected void onDetachedFromWindow ()

Added in API level 1

This is called when the view is detached from a window. At this point it no longer has a surface for drawing.

protected abstract void onLayout (boolean changed, int l, int t, int r, int b)

Added in API level 1

Called from layout when this view should assign a size and position to each of its children. Derived classes with children should override this method and call layout on each of their children.

Parameters

changed	This is a new size or position for this view
l	Left position, relative to parent
t	Top position, relative to parent
r	Right position, relative to parent
b	Bottom position, relative to parent

protected boolean onRequestFocusInDescendants (int direction, Rect previouslyFocusedRect)

Added in API level 1

Look for a descendant to call requestFocus() on. Called by requestFocus(int, android.graphics.Rect) when it wants to request focus within its children. Override this to customize how your ViewGroup requests focus within its children.

Parameters

direction	One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT
previouslyFocusedRect	The rectangle (in this View's coordinate system) to give a finer grained hint about where focus is coming from. May be null if there is no hint.

Returns

Whether focus was taken.

protected void removeDetachedView (View child, boolean animate)

Added in API level 1

Finishes the removal of a detached view. This method will dispatch the detached from window event and notify the hierarchy change listener.

This method is intended to be lightweight and makes no assumptions about whether the parent or child should be redrawn. Proper use of this method will include also making any appropriate requestLayout() or invalidate() calls. For example, callers can post a Runnable which performs a requestLayout() on the next frame, after all detach/remove calls are finished, causing layout to be run prior to redrawing the view hierarchy.

Parameters

child	the child to be definitely removed from the view hierarchy
animate	if true and the view has an animation, the view is placed in the disappearing views list, otherwise, it is detached from the window

protected void setChildrenDrawingCacheEnabled (boolean enabled)

Added in API level 1

Enables or disables the drawing cache for each child of this view group.

Parameters

enabled	true to enable the cache, false to dispose of it

protected void setChildrenDrawingOrderEnabled (boolean enabled)

Added in API level 7

Tells the ViewGroup whether to draw its children in the order defined by the method getChildDrawingOrder(int, int).

Parameters

enabled	true if the order of the children when drawing is determined by `getChildDrawingOrder(int, int)`, false otherwise

protected void setChildrenDrawnWithCacheEnabled (boolean enabled)

Added in API level 1

Tells the ViewGroup to draw its children using their drawing cache. This property is ignored when isAlwaysDrawnWithCacheEnabled() is true. A child's drawing cache will be used only if it has been enabled. Subclasses should call this method to start and stop using the drawing cache when they perform performance sensitive operations, like scrolling or animating.

Parameters

enabled	true if children should be drawn with their cache, false otherwise

protected void setStaticTransformationsEnabled (boolean enabled)

Added in API level 3

When this property is set to true, this ViewGroup supports static transformations on children; this causes getChildStaticTransformation(View, android.view.animation.Transformation) to be invoked when a child is drawn. Any subclass overriding getChildStaticTransformation(View, android.view.animation.Transformation) should set this property to true.

Parameters

enabled	True to enable static transformations on children, false otherwise.

Results

Interfaces

Classes

Enums

Exceptions

ViewGroup

Class Overview

Developer Guides

Summary

XML Attributes

android:addStatesFromChildren

Related Methods

android:alwaysDrawnWithCache

Related Methods

android:animateLayoutChanges

Related Methods

android:animationCache

Related Methods

android:clipChildren

Related Methods

android:clipToPadding

Related Methods

android:descendantFocusability

Related Methods

android:layoutAnimation

Related Methods

android:layoutMode

Related Methods

android:persistentDrawingCache

Related Methods

android:splitMotionEvents

Related Methods

Constants

protected static final int CLIP_TO_PADDING_MASK

public static final int FOCUS_AFTER_DESCENDANTS

public static final int FOCUS_BEFORE_DESCENDANTS

public static final int FOCUS_BLOCK_DESCENDANTS

public static final int LAYOUT_MODE_CLIP_BOUNDS

public static final int LAYOUT_MODE_OPTICAL_BOUNDS

public static final int PERSISTENT_ALL_CACHES

public static final int PERSISTENT_ANIMATION_CACHE

public static final int PERSISTENT_NO_CACHE

public static final int PERSISTENT_SCROLLING_CACHE

Public Constructors

public ViewGroup (Context context)

public ViewGroup (Context context, AttributeSet attrs)

public ViewGroup (Context context, AttributeSet attrs, int defStyle)

Public Methods

public void addChildrenForAccessibility (ArrayList<View> childrenForAccessibility)

Parameters

public void addFocusables (ArrayList<View> views, int direction, int focusableMode)

Parameters

public boolean addStatesFromChildren ()

public void addTouchables (ArrayList<View> views)

Parameters

public void addView (View child, int index, ViewGroup.LayoutParams params)

Parameters

public void addView (View child, ViewGroup.LayoutParams params)

Parameters

public void addView (View child, int index)

Parameters

See Also

public void addView (View child)

Parameters

See Also

public void addView (View child, int width, int height)

Parameters

public void bringChildToFront (View child)

Parameters

public void childDrawableStateChanged (View child)

Parameters

public void childHasTransientStateChanged (View child, boolean childHasTransientState)

Parameters

public void clearChildFocus (View child)

Parameters

public void clearDisappearingChildren ()

public void clearFocus ()

public void dispatchConfigurationChanged (Configuration newConfig)

Parameters

public void dispatchDisplayHint (int hint)