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.server.wm;
  
  import android.os.RemoteCallbackList;
  import android.os.RemoteException;
  import android.util.SparseArray;
  import android.view.IWallpaperVisibilityListener;
  
  /**
   * Manages and trigger wallpaper visibility listeners.
   */
  class WallpaperVisibilityListeners {
  
      /**
       * A map of displayIds and its listeners.
       */
      private final SparseArray<RemoteCallbackList<IWallpaperVisibilityListener>> mDisplayListeners =
              new SparseArray<>();
  
      void registerWallpaperVisibilityListener(IWallpaperVisibilityListener listener,
              int displayId) {
          RemoteCallbackList<IWallpaperVisibilityListener> listeners =
                  mDisplayListeners.get(displayId);
          if (listeners == null) {
              listeners = new RemoteCallbackList<>();
              mDisplayListeners.append(displayId, listeners);
          }
          listeners.register(listener);
      }
  
      void unregisterWallpaperVisibilityListener(IWallpaperVisibilityListener listener,
              int displayId) {
          RemoteCallbackList<IWallpaperVisibilityListener> listeners =
                  mDisplayListeners.get(displayId);
          if (listeners == null) {
              return;
          }
          listeners.unregister(listener);
      }
  
      void notifyWallpaperVisibilityChanged(DisplayContent displayContent) {
          final int displayId = displayContent.getDisplayId();
          final boolean visible = displayContent.mWallpaperController.isWallpaperVisible();
          RemoteCallbackList<IWallpaperVisibilityListener> displayListeners =
                  mDisplayListeners.get(displayId);
  
          // No listeners for this display.
          if (displayListeners == null) {
              return;
          }
  
          int i = displayListeners.beginBroadcast();
          while (i > 0) {
              i--;
              IWallpaperVisibilityListener listener = displayListeners.getBroadcastItem(i);
              try {
                  listener.onWallpaperVisibilityChanged(visible, displayId);
              } catch (RemoteException e) {
                  // Nothing to do in here, RemoteCallbackListener will clean it up.
              }
          }
          displayListeners.finishBroadcast();
      }
  }
  