Prevent error msg: 'Unrecoverable player error occurred' while playin…

…g video during rotation (#6502)

Playing a video in VideoDetailFragment and rotating the screen to landscape (back and forth more often)
can trigger this error message. Especially if rotation for whatever reason takes long or
playing a high resolution (1080p) video.

The underlying logcat error messages:
05-12 16:38:38.251 24920 26037 E Surface : getSlotFromBufferLocked: unknown buffer: 0x923fc810
05-12 16:38:38.251 24920 26037 W ACodec  : [OMX.qcom.video.decoder.avc] can not return buffer 35 to native window

The problem is that that Exoplayer is trying to write to our -- during rotation -- no longer existant
(VideoDetailFragment) SurfaceView.

Solution:
Implementing SurfaceHolder.Callback and using DummySurface we can now handle the lifecycle of the Surface.

How?: In case we are no longer able to write to the Surface eg. through rotation/putting in
background we can set a DummySurface. Although it only works on API >= 23.
Result: we get a little video interruption (audio is still fine) but we won't get the
'Unrecoverable player error occurred' error message.

This implementation is based on and more background information:
 'ExoPlayer stuck in buffering after re-adding the surface view a few time 2703'

 -> exoplayer fix suggestion link
  google/ExoPlayer#2703 (comment)

app/src/main/java/org/schabi/newpipe/player/Player.java

@@ -33,6 +33,7 @@
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.MotionEvent;
+import android.view.Surface;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.WindowManager;
@@ -112,6 +113,7 @@
 import org.schabi.newpipe.player.playback.MediaSourceManager;
 import org.schabi.newpipe.player.playback.PlaybackListener;
 import org.schabi.newpipe.player.playback.PlayerMediaSession;
+import org.schabi.newpipe.player.playback.SurfaceHolderCallback;
 import org.schabi.newpipe.player.playqueue.PlayQueue;
 import org.schabi.newpipe.player.playqueue.PlayQueueAdapter;
 import org.schabi.newpipe.player.playqueue.PlayQueueItem;
@@ -267,6 +269,7 @@ public final class Player implements
     private SimpleExoPlayer simpleExoPlayer;
     private AudioReactor audioReactor;
     private MediaSessionManager mediaSessionManager;
+    @Nullable private SurfaceHolderCallback surfaceHolderCallback;
 
     @NonNull private final CustomTrackSelector trackSelector;
     @NonNull private final LoadController loadController;
@@ -489,7 +492,7 @@ private void initPlayer(final boolean playOnReady) {
         registerBroadcastReceiver();
 
         // Setup video view
-        simpleExoPlayer.setVideoSurfaceView(binding.surfaceView);
+        setupVideoSurface();
         simpleExoPlayer.addVideoListener(this);
 
         // Setup subtitle view
@@ -768,8 +771,12 @@ private void destroyPlayer() {
         if (DEBUG) {
             Log.d(TAG, "destroyPlayer() called");
         }
+
+        cleanupVideoSurface();
+
         if (!exoPlayerIsNull()) {
             simpleExoPlayer.removeListener(this);
+            simpleExoPlayer.removeVideoListener(this);
             simpleExoPlayer.stop();
             simpleExoPlayer.release();
         }
@@ -4232,6 +4239,36 @@ public ExpandableSurfaceView getSurfaceView() {
     public PlayQueueAdapter getPlayQueueAdapter() {
         return playQueueAdapter;
     }
-
     //endregion
+
+
+    //region SurfaceHolderCallback helpers
+    private void setupVideoSurface() {
+        // make sure there is nothing left over from previous calls
+        cleanupVideoSurface();
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { // >=API23
+            surfaceHolderCallback = new SurfaceHolderCallback(context, simpleExoPlayer);
+            binding.surfaceView.getHolder().addCallback(surfaceHolderCallback);
+            final Surface surface = binding.surfaceView.getHolder().getSurface();
+            // initially set the surface manually otherwise
+            // onRenderedFirstFrame() will not be called
+            simpleExoPlayer.setVideoSurface(surface);
+        } else {
+            simpleExoPlayer.setVideoSurfaceView(binding.surfaceView);
+        }
+    }
+
+    private void cleanupVideoSurface() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { // >=API23
+            if (surfaceHolderCallback != null) {
+                if (binding != null) {
+                    binding.surfaceView.getHolder().removeCallback(surfaceHolderCallback);
+                }
+                surfaceHolderCallback.release();
+                surfaceHolderCallback = null;
+            }
+        }
+    }
+    //endregion SurfaceHolderCallback helpers
 }

app/src/main/java/org/schabi/newpipe/player/playback/SurfaceHolderCallback.java

@@ -0,0 +1,62 @@
+package org.schabi.newpipe.player.playback;
+
+import android.content.Context;
+import android.view.SurfaceHolder;
+
+import com.google.android.exoplayer2.SimpleExoPlayer;
+import com.google.android.exoplayer2.video.DummySurface;
+
+/**
+ * Prevent error message: 'Unrecoverable player error occurred'
+ * In case of rotation some users see this kind of an error which is preventable
+ * having a Callback that handles the lifecycle of the surface.
+ * <p>
+ * How?: In case we are no longer able to write to the surface eg. through rotation/putting in
+ * background we set set a DummySurface. Although it it works on API >= 23 only.
+ * Result: we get a little video interruption (audio is still fine) but we won't get the
+ * 'Unrecoverable player error occurred' error message.
+ * <p>
+ * This implementation is based on:
+ * 'ExoPlayer stuck in buffering after re-adding the surface view a few time #2703'
+ * <p>
+ * -> exoplayer fix suggestion link
+ * https://github.com/google/ExoPlayer/issues/2703#issuecomment-300599981
+ */
+public final class SurfaceHolderCallback implements SurfaceHolder.Callback {
+
+    private final Context context;
+    private final SimpleExoPlayer player;
+    private DummySurface dummySurface;
+
+    public SurfaceHolderCallback(final Context context, final SimpleExoPlayer player) {
+        this.context = context;
+        this.player = player;
+    }
+
+    @Override
+    public void surfaceCreated(final SurfaceHolder holder) {
+        player.setVideoSurface(holder.getSurface());
+    }
+
+    @Override
+    public void surfaceChanged(final SurfaceHolder holder,
+                               final int format,
+                               final int width,
+                               final int height) {
+    }
+
+    @Override
+    public void surfaceDestroyed(final SurfaceHolder holder) {
+        if (dummySurface == null) {
+            dummySurface = DummySurface.newInstanceV17(context, false);
+        }
+        player.setVideoSurface(dummySurface);
+    }
+
+    public void release() {
+        if (dummySurface != null) {
+            dummySurface.release();
+            dummySurface = null;
+        }
+    }
+}