Remove auto-notification of current cues when adding listener.

Users of addTextOutput should instead query the current cues if they
need them. This is more consistent with how other listeners are handled.

PiperOrigin-RevId: 310112241

RELEASENOTES.md

@@ -3,6 +3,9 @@
 ### dev-v2 (not yet released)
 
 *   Core library:
+    *   Added `TextComponent.getCurrentCues` because the current cues are no
+        longer forwarded to a new `TextOutput` in `SimpleExoPlayer`
+        automatically.
     *   Add opt-in to verify correct thread usage with
         `SimpleExoPlayer.setThrowsWhenUsingWrongThread(true)`
         ([#4463](https://github.com/google/ExoPlayer/issues/4463)).

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

@@ -30,6 +30,7 @@ import com.google.android.exoplayer2.device.DeviceInfo;
 import com.google.android.exoplayer2.device.DeviceListener;
 import com.google.android.exoplayer2.metadata.MetadataOutput;
 import com.google.android.exoplayer2.source.TrackGroupArray;
+import com.google.android.exoplayer2.text.Cue;
 import com.google.android.exoplayer2.text.TextOutput;
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.util.Util;
@@ -348,6 +349,9 @@ public interface Player {
      * @param listener The output to remove.
      */
     void removeTextOutput(TextOutput listener);
+
+    /** Returns the current {@link Cue Cues}. This list may be empty. */
+    List<Cue> getCurrentCues();
   }
 
   /** The metadata component of a {@link Player}. */

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

@@ -354,7 +354,6 @@ public class SimpleExoPlayer extends BasePlayer
   private final CopyOnWriteArraySet<AudioRendererEventListener> audioDebugListeners;
   private final BandwidthMeter bandwidthMeter;
   private final AnalyticsCollector analyticsCollector;
-
   private final AudioBecomingNoisyManager audioBecomingNoisyManager;
   private final AudioFocusManager audioFocusManager;
   private final StreamVolumeManager streamVolumeManager;
@@ -981,9 +980,6 @@ public class SimpleExoPlayer extends BasePlayer
 
   @Override
   public void addTextOutput(TextOutput listener) {
-    if (!currentCues.isEmpty()) {
-      listener.onCues(currentCues);
-    }
     textOutputs.add(listener);
   }
 
@@ -992,6 +988,12 @@ public class SimpleExoPlayer extends BasePlayer
     textOutputs.remove(listener);
   }
 
+  @Override
+  public List<Cue> getCurrentCues() {
+    verifyApplicationThread();
+    return currentCues;
+  }
+
   /**
    * Sets an output to receive text events, removing all existing outputs.
    *

library/core/src/main/java/com/google/android/exoplayer2/text/TextOutput.java

@@ -23,9 +23,9 @@ import java.util.List;
 public interface TextOutput {
 
   /**
-   * Called when there is a change in the {@link Cue}s.
+   * Called when there is a change in the {@link Cue Cues}.
    *
-   * @param cues The {@link Cue}s. May be empty.
+   * @param cues The {@link Cue Cues}. May be empty.
    */
   void onCues(List<Cue> cues);
 }

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

@@ -580,13 +580,13 @@ public class PlayerView extends FrameLayout implements AdsLoader.AdViewProvider
         oldTextComponent.removeTextOutput(componentListener);
       }
     }
+    if (subtitleView != null) {
+      subtitleView.setCues(null);
+    }
     this.player = player;
     if (useController()) {
       controller.setPlayer(player);
     }
-    if (subtitleView != null) {
-      subtitleView.setCues(null);
-    }
     updateBuffering();
     updateErrorMessage();
     updateForCurrentTrackSelections(/* isNewPlayer= */ true);
@@ -608,6 +608,9 @@ public class PlayerView extends FrameLayout implements AdsLoader.AdViewProvider
       @Nullable Player.TextComponent newTextComponent = player.getTextComponent();
       if (newTextComponent != null) {
         newTextComponent.addTextOutput(componentListener);
+        if (subtitleView != null) {
+          subtitleView.setCues(newTextComponent.getCurrentCues());
+        }
       }
       player.addListener(componentListener);
       maybeShowController(false);