ViewCompat

Automatically determine whether a view is important for accessibility.

The view is not important for accessibility.

The view is important for accessibility.

Always allow a user to over-scroll this view, provided it is a view that can scroll.

Allow a user to over-scroll this view only if the content is large enough to meaningfully scroll, provided it is a view that can scroll.

Never allow a user to over-scroll this view.

Check if this view can be scrolled horizontally in a certain direction.

Check if this view can be scrolled vertically in a certain direction.

Gets the provider for managing a virtual view hierarchy rooted at this View and reported to AccessibilityServices that explore the window content.

If this method returns an instance, this instance is responsible for managing AccessibilityNodeInfoCompats describing the virtual sub-tree rooted at this View including the one representing the View itself. Similarly the returned instance is responsible for performing accessibility actions on any virtual view or the root view itself.

If an AccessibilityDelegateCompat has been specified via calling its {@link AccessibilityDelegateCompat#getAccessibilityNodeProvider(View) is responsible for handling this call.

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.

Returns the over-scroll mode for this view. The result will be one of OVER_SCROLL_ALWAYS (default), OVER_SCROLL_IF_CONTENT_SCROLLS (allow over-scrolling only if the view content is larger than the container), or OVER_SCROLL_NEVER.

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.

Initializes an AccessibilityEvent with information about this View which is the event source. In other words, the source of an accessibility event is the view whose state change triggered firing the event.

Example: Setting the password property of an event in addition to properties set by the super implementation:

 public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
     super.onInitializeAccessibilityEvent(event);
     event.setPassword(true);
 }

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

Note: Always call the super implementation before adding information to the event, in case the default implementation has basic information to add.

Initializes an AccessibilityNodeInfo with information about this view. The base implementation sets:

• setParent(View),
• setBoundsInParent(Rect),
• setBoundsInScreen(Rect),
• setPackageName(CharSequence),
• setClassName(CharSequence),
• setContentDescription(CharSequence),
• setEnabled(boolean),
• setClickable(boolean),
• setFocusable(boolean),
• setFocused(boolean),
• setLongClickable(boolean),
• setSelected(boolean),

Subclasses should override this method, call the super implementation, and set additional attributes.

If an View.AccessibilityDelegate has been specified via calling setAccessibilityDelegate(android.view.View.AccessibilityDelegate) its onInitializeAccessibilityNodeInfo(View, android.view.accessibility.AccessibilityNodeInfo) is responsible for handling this call.

Called from dispatchPopulateAccessibilityEvent(AccessibilityEvent) giving a chance to this View to populate the accessibility event with its text content. While this method is free to modify event attributes other than text content, doing so should normally be performed in onInitializeAccessibilityEvent(AccessibilityEvent).

Example: Adding formatted date string to an accessibility event in addition to the text added by the super implementation:

 public void onPopulateAccessibilityEvent(AccessibilityEvent event) {
     super.onPopulateAccessibilityEvent(event);
     final int flags = DateUtils.FORMAT_SHOW_DATE | DateUtils.FORMAT_SHOW_WEEKDAY;
     String selectedDateUtterance = DateUtils.formatDateTime(mContext,
         mCurrentDate.getTimeInMillis(), flags);
     event.getText().add(selectedDateUtterance);
 }

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

Note: Always call the super implementation before adding information to the event, in case the default implementation has basic information to add.

Cause an invalidate to happen on the next animation time step, typically the next display frame.

This method can be invoked from outside of the UI thread only when this View is attached to a window.

Cause an invalidate of the specified area to happen on the next animation time step, typically the next display frame.

This method can be invoked from outside of the UI thread only when this View is attached to a window.

Causes the Runnable to execute on the next animation time step. The runnable will be run on the user interface thread.

This method can be invoked from outside of the UI thread only when this View is attached to a window.

Causes the Runnable to execute on the next animation time step, after the specified amount of time elapses. The runnable will be run on the user interface thread.

This method can be invoked from outside of the UI thread only when this View is attached to a window.

Sets a delegate for implementing accessibility support via compositon as opposed to inheritance. The delegate's primary use is for implementing backwards compatible widgets. For more details see View.AccessibilityDelegate.

Set whether this view is currently tracking transient state that the framework should attempt to preserve when possible.

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.

Set the over-scroll mode for this view. Valid over-scroll modes are OVER_SCROLL_ALWAYS (default), OVER_SCROLL_IF_CONTENT_SCROLLS (allow over-scrolling only if the view content is larger than the container), or OVER_SCROLL_NEVER. Setting the over-scroll mode of a view will have an effect only if the view is capable of scrolling.