Add dispatchPrepare(player) to ControlDispatcher

Issue: #7882
PiperOrigin-RevId: 341394254

RELEASENOTES.md

@@ -29,6 +29,13 @@
 *   UI:
     *   Show overflow button in `StyledPlayerControlView` only when there is not
         enough space.
+    *   Add `dispatchPrepare(Player)` to `ControlDispatcher` and implement it in
+        `DefaultControlDispatcher`. Deprecate `PlaybackPreparer` and
+        `setPlaybackPreparer` in `StyledPlayerView`, `StyledPlayerControlView`,
+        `PlayerView`, `PlayerControlView`, `PlayerNotificationManager` and
+        `LeanbackPlayerAdapter` and use `ControlDispatcher` for dispatching
+        prepare instead
+        ([#7882](https://github.com/google/ExoPlayer/issues/7882)).
 *   Audio:
     *   Retry playback after some types of `AudioTrack` error.
 *   Extractors:

demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -34,7 +34,6 @@
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.ExoPlaybackException;
 import com.google.android.exoplayer2.MediaItem;
-import com.google.android.exoplayer2.PlaybackPreparer;
 import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.RenderersFactory;
 import com.google.android.exoplayer2.SimpleExoPlayer;
@@ -68,7 +67,7 @@
 
 /** An activity that plays media using {@link SimpleExoPlayer}. */
 public class PlayerActivity extends AppCompatActivity
-    implements OnClickListener, PlaybackPreparer, StyledPlayerControlView.VisibilityListener {
+    implements OnClickListener, StyledPlayerControlView.VisibilityListener {
 
   // Saved instance state keys.
 
@@ -250,13 +249,6 @@ public void onClick(View view) {
     }
   }
 
-  // PlaybackPreparer implementation
-
-  @Override
-  public void preparePlayback() {
-    player.prepare();
-  }
-
   // PlayerControlView.VisibilityListener implementation
 
   @Override
@@ -302,7 +294,6 @@ protected boolean initializePlayer() {
       player.setAudioAttributes(AudioAttributes.DEFAULT, /* handleAudioFocus= */ true);
       player.setPlayWhenReady(startAutoPlay);
       playerView.setPlayer(player);
-      playerView.setPlaybackPreparer(this);
       debugViewHelper = new DebugTextViewHelper(player, debugTextView);
       debugViewHelper.start();
     }

extensions/leanback/src/main/java/com/google/android/exoplayer2/ext/leanback/LeanbackPlayerAdapter.java

@@ -78,10 +78,15 @@ public LeanbackPlayerAdapter(Context context, Player player, final int updatePer
   }
 
   /**
-   * Sets the {@link PlaybackPreparer}.
-   *
-   * @param playbackPreparer The {@link PlaybackPreparer}.
+   * @deprecated Use {@link #setControlDispatcher(ControlDispatcher)} instead. The adapter calls
+   *     {@link ControlDispatcher#dispatchPrepare(Player)} instead of {@link
+   *     PlaybackPreparer#preparePlayback()}. The {@link DefaultControlDispatcher} that the adapter
+   *     uses by default, calls {@link Player#prepare()}. If you wish to customize this behaviour,
+   *     you can provide a custom implementation of {@link
+   *     ControlDispatcher#dispatchPrepare(Player)}.
    */
+  @SuppressWarnings("deprecation")
+  @Deprecated
   public void setPlaybackPreparer(@Nullable PlaybackPreparer playbackPreparer) {
     this.playbackPreparer = playbackPreparer;
   }
@@ -167,11 +172,15 @@ public long getCurrentPosition() {
     return player.getPlaybackState() == Player.STATE_IDLE ? -1 : player.getCurrentPosition();
   }
 
+  // Calls deprecated method to provide backwards compatibility.
+  @SuppressWarnings("deprecation")
   @Override
   public void play() {
     if (player.getPlaybackState() == Player.STATE_IDLE) {
       if (playbackPreparer != null) {
         playbackPreparer.preparePlayback();
+      } else {
+        controlDispatcher.dispatchPrepare(player);
       }
     } else if (player.getPlaybackState() == Player.STATE_ENDED) {
       controlDispatcher.dispatchSeekTo(player, player.getCurrentWindowIndex(), C.TIME_UNSET);

extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/MediaSessionConnector.java

@@ -1147,6 +1147,8 @@ public void onPlay() {
         if (player.getPlaybackState() == Player.STATE_IDLE) {
           if (playbackPreparer != null) {
             playbackPreparer.onPrepare(/* playWhenReady= */ true);
+          } else {
+            controlDispatcher.dispatchPrepare(player);
           }
         } else if (player.getPlaybackState() == Player.STATE_ENDED) {
           seekTo(player, player.getCurrentWindowIndex(), C.TIME_UNSET);

library/core/src/main/java/com/google/android/exoplayer2/ControlDispatcher.java

@@ -26,6 +26,14 @@
  */
 public interface ControlDispatcher {
 
+  /**
+   * Dispatches a {@link Player#prepare()} operation.
+   *
+   * @param player The {@link Player} to which the operation should be dispatched.
+   * @return True if the operation was dispatched. False if suppressed.
+   */
+  boolean dispatchPrepare(Player player);
+
   /**
    * Dispatches a {@link Player#setPlayWhenReady(boolean)} operation.
    *

library/core/src/main/java/com/google/android/exoplayer2/DefaultControlDispatcher.java

@@ -52,6 +52,12 @@ public DefaultControlDispatcher(long fastForwardIncrementMs, long rewindIncremen
     window = new Timeline.Window();
   }
 
+  @Override
+  public boolean dispatchPrepare(Player player) {
+    player.prepare();
+    return true;
+  }
+
   @Override
   public boolean dispatchSetPlayWhenReady(Player player, boolean playWhenReady) {
     player.setPlayWhenReady(playWhenReady);

library/core/src/main/java/com/google/android/exoplayer2/PlaybackPreparer.java

@@ -15,9 +15,11 @@
  */
 package com.google.android.exoplayer2;
 
-/** Called to prepare a playback. */
+/** @deprecated Use {@link ControlDispatcher} instead. */
+@Deprecated
 public interface PlaybackPreparer {
 
-  /** Called to prepare a playback. */
+  /** @deprecated Use {@link ControlDispatcher#dispatchPrepare(Player)} instead. */
+  @Deprecated
   void preparePlayback();
 }

library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerControlView.java

@@ -611,11 +611,15 @@ public void setProgressUpdateListener(@Nullable ProgressUpdateListener listener)
   }
 
   /**
-   * Sets the {@link PlaybackPreparer}.
-   *
-   * @param playbackPreparer The {@link PlaybackPreparer}, or null to remove the current playback
-   *     preparer.
+   * @deprecated Use {@link #setControlDispatcher(ControlDispatcher)} instead. The view calls {@link
+   *     ControlDispatcher#dispatchPrepare(Player)} instead of {@link
+   *     PlaybackPreparer#preparePlayback()}. The {@link DefaultControlDispatcher} that the view
+   *     uses by default, calls {@link Player#prepare()}. If you wish to customize this behaviour,
+   *     you can provide a custom implementation of {@link
+   *     ControlDispatcher#dispatchPrepare(Player)}.
    */
+  @SuppressWarnings("deprecation")
+  @Deprecated
   public void setPlaybackPreparer(@Nullable PlaybackPreparer playbackPreparer) {
     this.playbackPreparer = playbackPreparer;
   }
@@ -1254,11 +1258,14 @@ private void dispatchPlayPause(Player player) {
     }
   }
 
+  @SuppressWarnings("deprecation")
   private void dispatchPlay(Player player) {
     @State int state = player.getPlaybackState();
     if (state == Player.STATE_IDLE) {
       if (playbackPreparer != null) {
         playbackPreparer.preparePlayback();
+      } else {
+        controlDispatcher.dispatchPrepare(player);
       }
     } else if (state == Player.STATE_ENDED) {
       seekTo(player, player.getCurrentWindowIndex(), C.TIME_UNSET);

library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerNotificationManager.java

@@ -682,10 +682,16 @@ public final void setPlayer(@Nullable Player player) {
   }
 
   /**
-   * Sets the {@link PlaybackPreparer}.
-   *
-   * @param playbackPreparer The {@link PlaybackPreparer}.
+   * @deprecated Use {@link #setControlDispatcher(ControlDispatcher)} instead. The manager calls
+   *     {@link ControlDispatcher#dispatchPrepare(Player)} instead of {@link
+   *     PlaybackPreparer#preparePlayback()}. The {@link DefaultControlDispatcher} that this manager
+   *     uses by default, calls {@link Player#prepare()}. If you wish to intercept or customize this
+   *     behaviour, you can provide a custom implementation of {@link
+   *     ControlDispatcher#dispatchPrepare(Player)} and pass it to {@link
+   *     #setControlDispatcher(ControlDispatcher)}.
    */
+  @SuppressWarnings("deprecation")
+  @Deprecated
   public void setPlaybackPreparer(@Nullable PlaybackPreparer playbackPreparer) {
     this.playbackPreparer = playbackPreparer;
   }
@@ -1039,8 +1045,7 @@ protected NotificationCompat.Builder createNotification(
       @Nullable NotificationCompat.Builder builder,
       boolean ongoing,
       @Nullable Bitmap largeIcon) {
-    if (player.getPlaybackState() == Player.STATE_IDLE
-        && (player.getCurrentTimeline().isEmpty() || playbackPreparer == null)) {
+    if (player.getPlaybackState() == Player.STATE_IDLE && player.getCurrentTimeline().isEmpty()) {
       builderActions = null;
       return null;
     }
@@ -1369,6 +1374,7 @@ public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
 
   private class NotificationBroadcastReceiver extends BroadcastReceiver {
 
+    @SuppressWarnings("deprecation")
     @Override
     public void onReceive(Context context, Intent intent) {
       Player player = PlayerNotificationManager.this.player;
@@ -1382,6 +1388,8 @@ public void onReceive(Context context, Intent intent) {
         if (player.getPlaybackState() == Player.STATE_IDLE) {
           if (playbackPreparer != null) {
             playbackPreparer.preparePlayback();
+          } else {
+            controlDispatcher.dispatchPrepare(player);
           }
         } else if (player.getPlaybackState() == Player.STATE_ENDED) {
           controlDispatcher.dispatchSeekTo(player, player.getCurrentWindowIndex(), C.TIME_UNSET);

library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerView.java

@@ -982,11 +982,15 @@ public void setControllerVisibilityListener(
   }
 
   /**
-   * Sets the {@link PlaybackPreparer}.
-   *
-   * @param playbackPreparer The {@link PlaybackPreparer}, or null to remove the current playback
-   *     preparer.
+   * @deprecated Use {@link #setControlDispatcher(ControlDispatcher)} instead. The view calls {@link
+   *     ControlDispatcher#dispatchPrepare(Player)} instead of {@link
+   *     PlaybackPreparer#preparePlayback()}. The {@link DefaultControlDispatcher} that the view
+   *     uses by default, calls {@link Player#prepare()}. If you wish to customize this behaviour,
+   *     you can provide a custom implementation of {@link
+   *     ControlDispatcher#dispatchPrepare(Player)}.
    */
+  @SuppressWarnings("deprecation")
+  @Deprecated
   public void setPlaybackPreparer(@Nullable PlaybackPreparer playbackPreparer) {
     Assertions.checkStateNotNull(controller);
     controller.setPlaybackPreparer(playbackPreparer);

library/ui/src/main/java/com/google/android/exoplayer2/ui/StyledPlayerControlView.java

@@ -834,11 +834,15 @@ public void setProgressUpdateListener(@Nullable ProgressUpdateListener listener)
   }
 
   /**
-   * Sets the {@link PlaybackPreparer}.
-   *
-   * @param playbackPreparer The {@link PlaybackPreparer}, or null to remove the current playback
-   *     preparer.
+   * @deprecated Use {@link #setControlDispatcher(ControlDispatcher)} instead. The view calls {@link
+   *     ControlDispatcher#dispatchPrepare(Player)} instead of {@link
+   *     PlaybackPreparer#preparePlayback()}. The {@link DefaultControlDispatcher} that the view
+   *     uses by default, calls {@link Player#prepare()}. If you wish to customize this behaviour,
+   *     you can provide a custom implementation of {@link
+   *     ControlDispatcher#dispatchPrepare(Player)}.
    */
+  @SuppressWarnings("deprecation")
+  @Deprecated
   public void setPlaybackPreparer(@Nullable PlaybackPreparer playbackPreparer) {
     this.playbackPreparer = playbackPreparer;
   }
@@ -1698,11 +1702,14 @@ private void dispatchPlayPause(Player player) {
     }
   }
 
+  @SuppressWarnings("deprecation")
   private void dispatchPlay(Player player) {
     @State int state = player.getPlaybackState();
     if (state == Player.STATE_IDLE) {
       if (playbackPreparer != null) {
         playbackPreparer.preparePlayback();
+      } else {
+        controlDispatcher.dispatchPrepare(player);
       }
     } else if (state == Player.STATE_ENDED) {
       seekTo(player, player.getCurrentWindowIndex(), C.TIME_UNSET);

library/ui/src/main/java/com/google/android/exoplayer2/ui/StyledPlayerView.java

@@ -45,6 +45,7 @@
 import androidx.core.content.ContextCompat;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.ControlDispatcher;
+import com.google.android.exoplayer2.DefaultControlDispatcher;
 import com.google.android.exoplayer2.ExoPlaybackException;
 import com.google.android.exoplayer2.PlaybackPreparer;
 import com.google.android.exoplayer2.Player;
@@ -977,11 +978,15 @@ public void setControllerOnFullScreenModeChangedListener(
   }
 
   /**
-   * Sets the {@link PlaybackPreparer}.
-   *
-   * @param playbackPreparer The {@link PlaybackPreparer}, or null to remove the current playback
-   *     preparer.
+   * @deprecated Use {@link #setControlDispatcher(ControlDispatcher)} instead. The view calls {@link
+   *     ControlDispatcher#dispatchPrepare(Player)} instead of {@link
+   *     PlaybackPreparer#preparePlayback()}. The {@link DefaultControlDispatcher} that the view
+   *     uses by default, calls {@link Player#prepare()}. If you wish to customize this behaviour,
+   *     you can provide a custom implementation of {@link
+   *     ControlDispatcher#dispatchPrepare(Player)}.
    */
+  @SuppressWarnings("deprecation")
+  @Deprecated
   public void setPlaybackPreparer(@Nullable PlaybackPreparer playbackPreparer) {
     Assertions.checkStateNotNull(controller);
     controller.setPlaybackPreparer(playbackPreparer);