content: /*
   * Copyright (C) 2017 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.android.internal.widget;
  
  import android.os.Bundle;
  import android.view.View;
  import android.view.View.AccessibilityDelegate;
  import android.view.accessibility.AccessibilityEvent;
  import android.view.accessibility.AccessibilityNodeInfo;
  
  /**
   * The AccessibilityDelegate used by RecyclerView.
   * <p>
   * This class handles basic accessibility actions and delegates them to LayoutManager.
   */
  public class RecyclerViewAccessibilityDelegate extends AccessibilityDelegate {
      final RecyclerView mRecyclerView;
  
  
      public RecyclerViewAccessibilityDelegate(RecyclerView recyclerView) {
          mRecyclerView = recyclerView;
      }
  
      boolean shouldIgnore() {
          return mRecyclerView.hasPendingAdapterUpdates();
      }
  
      @Override
      public boolean performAccessibilityAction(View host, int action, Bundle args) {
          if (super.performAccessibilityAction(host, action, args)) {
              return true;
          }
          if (!shouldIgnore() && mRecyclerView.getLayoutManager() != null) {
              return mRecyclerView.getLayoutManager().performAccessibilityAction(action, args);
          }
  
          return false;
      }
  
      @Override
      public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) {
          super.onInitializeAccessibilityNodeInfo(host, info);
          info.setClassName(RecyclerView.class.getName());
          if (!shouldIgnore() && mRecyclerView.getLayoutManager() != null) {
              mRecyclerView.getLayoutManager().onInitializeAccessibilityNodeInfo(info);
          }
      }
  
      @Override
      public void onInitializeAccessibilityEvent(View host, AccessibilityEvent event) {
          super.onInitializeAccessibilityEvent(host, event);
          event.setClassName(RecyclerView.class.getName());
          if (host instanceof RecyclerView && !shouldIgnore()) {
              RecyclerView rv = (RecyclerView) host;
              if (rv.getLayoutManager() != null) {
                  rv.getLayoutManager().onInitializeAccessibilityEvent(event);
              }
          }
      }
  
      /**
       * Gets the AccessibilityDelegate for an individual item in the RecyclerView.
       * A basic item delegate is provided by default, but you can override this
       * method to provide a custom per-item delegate.
       */
      public AccessibilityDelegate getItemDelegate() {
          return mItemDelegate;
      }
  
      final AccessibilityDelegate mItemDelegate = new AccessibilityDelegate() {
          @Override
          public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) {
              super.onInitializeAccessibilityNodeInfo(host, info);
              if (!shouldIgnore() && mRecyclerView.getLayoutManager() != null) {
                  mRecyclerView.getLayoutManager()
                          .onInitializeAccessibilityNodeInfoForItem(host, info);
              }
          }
  
          @Override
          public boolean performAccessibilityAction(View host, int action, Bundle args) {
              if (super.performAccessibilityAction(host, action, args)) {
                  return true;
              }
              if (!shouldIgnore() && mRecyclerView.getLayoutManager() != null) {
                  return mRecyclerView.getLayoutManager()
                          .performAccessibilityActionForItem(host, action, args);
              }
              return false;
          }
      };
  }
  
  