Merge "docs: Modernized AccessibilityNodeProvider example" into qt-dev am: e49cbb3a5d (8f473fb2) · Commits · e / os / android_frameworks_base

core/java/android/view/accessibility/AccessibilityNodeProvider.java

+114 −16

Original line number	Diff line number	Diff line
		@@ -44,28 +44,126 @@ import java.util.List;
		* View itself. Similarly the returned instance is responsible for performing accessibility
		* actions on any virtual view or the root view itself. For example:
		* </p>
		* <pre>
		* getAccessibilityNodeProvider(
		* if (mAccessibilityNodeProvider == null) {
		* mAccessibilityNodeProvider = new AccessibilityNodeProvider() {
		* public boolean performAction(int action, int virtualDescendantId) {
		* // Implementation.
		* return false;
		* <div>
		* <div class="ds-selector-tabs"><section><h3 id="kotlin">Kotlin</h3>
		* <pre class="prettyprint lang-kotlin">
		* // "view" is the View instance on which this class performs accessibility functions.
		* class MyCalendarViewAccessibilityDelegate(
		* private var view: MyCalendarView) : AccessibilityDelegate() {
		* override fun getAccessibilityNodeProvider(host: View): AccessibilityNodeProvider {
		* return object : AccessibilityNodeProvider() {
		* override fun createAccessibilityNodeInfo(virtualViewId: Int):
		* AccessibilityNodeInfo? {
		* when (virtualViewId) {
		* <var>host-view-id</var> -> {
		* val node = AccessibilityNodeInfo.obtain(view)
		* node.addChild(view, <var>child-view-id</var>)
		* // Set other attributes like screenReaderFocusable
		* // and contentDescription.
		* return node
		* }
		* <var>child-view-id</var> -> {
		* val node = AccessibilityNodeInfo
		* .obtain(view, virtualViewId)
		* node.setParent(view)
		* node.addAction(ACTION_SCROLL_UP)
		* node.addAction(ACTION_SCROLL_DOWN)
		* // Set other attributes like focusable and visibleToUser.
		* node.setBoundsInScreen(
		* Rect(<var>coords-of-edges-relative-to-screen</var>))
		* return node
		* }
		* else -> return null
		* }
		* }
		*
		* public List<AccessibilityNodeInfo> findAccessibilityNodeInfosByText(String text,
		* int virtualDescendantId) {
		* // Implementation.
		* return null;
		* override fun performAction(
		* virtualViewId: Int,
		* action: Int,
		* arguments: Bundle
		* ): Boolean {
		* if (virtualViewId == <var>host-view-id</var>) {
		* return view.performAccessibilityAction(action, arguments)
		* }
		* when (action) {
		* ACTION_SCROLL_UP.id -> {
		* // Implement logic in a separate method.
		* navigateToPreviousMonth()
		*
		* public AccessibilityNodeInfo createAccessibilityNodeInfo(int virtualDescendantId) {
		* // Implementation.
		* return null;
		* return true
		* }
		* ACTION_SCROLL_DOWN.id ->
		* // Implement logic in a separate method.
		* navigateToNextMonth()
		*
		* return true
		* else -> return false
		* }
		* }
		* }
		* }
		* }
		* });
		* return mAccessibilityNodeProvider;
		* </pre>
		* </section><section><h3 id="java">Java</h3>
		* <pre class="prettyprint lang-java">
		* final class MyCalendarViewAccessibilityDelegate extends AccessibilityDelegate {
		* // The View instance on which this class performs accessibility functions.
		* private final MyCalendarView view;
		*
		* MyCalendarViewAccessibilityDelegate(MyCalendarView view) {
		* this.view = view;
		* }
		*
		* @Override
		* public AccessibilityNodeProvider getAccessibilityNodeProvider(View host) {
		* return new AccessibilityNodeProvider() {
		* @Override
		* @Nullable
		* public AccessibilityNodeInfo createAccessibilityNodeInfo(int virtualViewId) {
		* if (virtualViewId == <var>host-view-id</var>) {
		* AccessibilityNodeInfo node = AccessibilityNodeInfo.obtain(view);
		* node.addChild(view, <var>child-view-id</var>);
		* // Set other attributes like screenReaderFocusable and contentDescription.
		* return node;
		* } else if (virtualViewId == <var>child-view-id</var>) {
		* AccessibilityNodeInfo node =
		* AccessibilityNodeInfo.obtain(view, virtualViewId);
		* node.setParent(view);
		* node.addAction(ACTION_SCROLL_UP);
		* node.addAction(ACTION_SCROLL_DOWN);
		* // Set other attributes like focusable and visibleToUser.
		* node.setBoundsInScreen(
		* new Rect(<var>coordinates-of-edges-relative-to-screen</var>));
		* return node;
		* } else {
		* return null;
		* }
		* }
		*
		* @Override
		* public boolean performAction(int virtualViewId, int action, Bundle arguments) {
		* if (virtualViewId == <var>host-view-id</var>) {
		* return view.performAccessibilityAction(action, arguments);
		* }
		*
		* if (action == ACTION_SCROLL_UP.getId()) {
		* // Implement logic in a separate method.
		* navigateToPreviousMonth();
		*
		* return true;
		* } else if (action == ACTION_SCROLL_DOWN.getId()) {
		* // Implement logic in a separate method.
		* navigateToNextMonth();
		*
		* return true;
		* } else {
		* return false;
		* }
		* }
		* };
		* }
		* }
		* </pre></section></div></div>
		*/
		public abstract class AccessibilityNodeProvider {