Add error and buffering views to PlayerView

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195203362

RELEASENOTES.md

@@ -12,9 +12,12 @@
   `SimpleExoPlayer` to receive detailed meta data for each ExoPlayer event.
 * Added `getPlaybackError` to `Player` interface.
 * UI components:
+  * Add support for displaying error messages and a buffering spinner in
+    `PlayerView`.
   * Add support for listening to `AspectRatioFrameLayout`'s aspect ratio update
     ([#3736](https://github.com/google/ExoPlayer/issues/3736)).
-  * Add PlayerNotificationManager.
+  * Add `PlayerNotificationManager` for displaying notifications reflecting the
+    player state.
 * Downloading: Add `DownloadService`, `DownloadManager` and
   related classes ([#2643](https://github.com/google/ExoPlayer/issues/2643)).
 * MediaSources:

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

@@ -81,6 +81,7 @@ import com.google.android.exoplayer2.ui.TrackSelectionView;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DefaultBandwidthMeter;
 import com.google.android.exoplayer2.upstream.HttpDataSource;
+import com.google.android.exoplayer2.util.ErrorMessageProvider;
 import com.google.android.exoplayer2.util.EventLogger;
 import com.google.android.exoplayer2.util.ParcelableArray;
 import com.google.android.exoplayer2.util.Util;
@@ -143,7 +144,6 @@ public class PlayerActivity extends Activity
   private DefaultTrackSelector trackSelector;
   private DefaultTrackSelector.Parameters trackSelectorParameters;
   private DebugTextViewHelper debugViewHelper;
-  private boolean inErrorState;
   private TrackGroupArray lastSeenTrackGroupArray;
 
   private boolean startAutoPlay;
@@ -174,6 +174,7 @@ public class PlayerActivity extends Activity
 
     playerView = findViewById(R.id.player_view);
     playerView.setControllerVisibilityListener(this);
+    playerView.setErrorMessageProvider(new PlayerErrorMessageProvider());
     playerView.requestFocus();
 
     if (savedInstanceState != null) {
@@ -235,17 +236,17 @@ public class PlayerActivity extends Activity
   @Override
   public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
       @NonNull int[] grantResults) {
-    if (grantResults.length > 0) {
+    if (grantResults.length == 0) {
+      // Empty results are triggered if a permission is requested while another request was already
+      // pending and can be safely ignored in this case.
+      return;
+    }
     if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
       initializePlayer();
     } else {
       showToast(R.string.storage_permission_denied);
       finish();
     }
-    } else {
-      // Empty results are triggered if a permission is requested while another request was already
-      // pending and can be safely ignored in this case.
-    }
   }
 
   @Override
@@ -440,7 +441,6 @@ public class PlayerActivity extends Activity
       player.seekTo(startWindow, startPosition);
     }
     player.prepare(mediaSource, !haveStartPosition, false);
-    inErrorState = false;
     updateButtonVisibilities();
   }
 
@@ -486,8 +486,10 @@ public class PlayerActivity extends Activity
   private DefaultDrmSessionManager<FrameworkMediaCrypto> buildDrmSessionManagerV18(
       UUID uuid, String licenseUrl, String[] keyRequestPropertiesArray, boolean multiSession)
       throws UnsupportedDrmException {
-    HttpMediaDrmCallback drmCallback = new HttpMediaDrmCallback(licenseUrl,
+    HttpDataSource.Factory licenseDataSourceFactory =
-        buildHttpDataSourceFactory(false));
+        ((DemoApplication) getApplication()).buildHttpDataSourceFactory(/* listener= */ null);
+    HttpMediaDrmCallback drmCallback =
+        new HttpMediaDrmCallback(licenseUrl, licenseDataSourceFactory);
     if (keyRequestPropertiesArray != null) {
       for (int i = 0; i < keyRequestPropertiesArray.length - 1; i += 2) {
         drmCallback.setKeyRequestProperty(keyRequestPropertiesArray[i],
@@ -543,18 +545,6 @@ public class PlayerActivity extends Activity
         .buildDataSourceFactory(useBandwidthMeter ? BANDWIDTH_METER : null);
   }
 
-  /**
-   * Returns a new HttpDataSource factory.
-   *
-   * @param useBandwidthMeter Whether to set {@link #BANDWIDTH_METER} as a listener to the new
-   *     DataSource factory.
-   * @return A new HttpDataSource factory.
-   */
-  private HttpDataSource.Factory buildHttpDataSourceFactory(boolean useBandwidthMeter) {
-    return ((DemoApplication) getApplication())
-        .buildHttpDataSourceFactory(useBandwidthMeter ? BANDWIDTH_METER : null);
-  }
-
   /** Returns an ads media source, reusing the ads loader if one exists. */
   private @Nullable MediaSource createAdsMediaSource(MediaSource mediaSource, Uri adTagUri) {
     // Load the extension source using reflection so the demo app doesn't have to depend on it.
@@ -623,7 +613,7 @@ public class PlayerActivity extends Activity
       return;
     }
 
-    for (int i = 0; i < mappedTrackInfo.length; i++) {
+    for (int i = 0; i < mappedTrackInfo.getRendererCount(); i++) {
       TrackGroupArray trackGroups = mappedTrackInfo.getTrackGroups(i);
       if (trackGroups.length != 0) {
         Button button = new Button(this);
@@ -687,43 +677,15 @@ public class PlayerActivity extends Activity
 
     @Override
     public void onPositionDiscontinuity(@Player.DiscontinuityReason int reason) {
-      if (inErrorState) {
+      if (player.getPlaybackError() != null) {
-        // This will only occur if the user has performed a seek whilst in the error state. Update
+        // The user has performed a seek whilst in the error state. Update the resume position so
-        // the resume position so that if the user then retries, playback will resume from the
+        // that if the user then retries, playback resumes from the position to which they seeked.
-        // position to which they seeked.
         updateStartPosition();
       }
     }
 
     @Override
     public void onPlayerError(ExoPlaybackException e) {
-      String errorString = null;
-      if (e.type == ExoPlaybackException.TYPE_RENDERER) {
-        Exception cause = e.getRendererException();
-        if (cause instanceof DecoderInitializationException) {
-          // Special case for decoder initialization failures.
-          DecoderInitializationException decoderInitializationException =
-              (DecoderInitializationException) cause;
-          if (decoderInitializationException.decoderName == null) {
-            if (decoderInitializationException.getCause() instanceof DecoderQueryException) {
-              errorString = getString(R.string.error_querying_decoders);
-            } else if (decoderInitializationException.secureDecoderRequired) {
-              errorString = getString(R.string.error_no_secure_decoder,
-                  decoderInitializationException.mimeType);
-            } else {
-              errorString = getString(R.string.error_no_decoder,
-                  decoderInitializationException.mimeType);
-            }
-          } else {
-            errorString = getString(R.string.error_instantiating_decoder,
-                decoderInitializationException.decoderName);
-          }
-        }
-      }
-      if (errorString != null) {
-        showToast(errorString);
-      }
-      inErrorState = true;
       if (isBehindLiveWindow(e)) {
         clearStartPosition();
         initializePlayer();
@@ -753,7 +715,40 @@ public class PlayerActivity extends Activity
         lastSeenTrackGroupArray = trackGroups;
       }
     }
+  }
 
+  private class PlayerErrorMessageProvider implements ErrorMessageProvider<ExoPlaybackException> {
+
+    @Override
+    public Pair<Integer, String> getErrorMessage(ExoPlaybackException e) {
+      String errorString = getString(R.string.error_generic);
+      if (e.type == ExoPlaybackException.TYPE_RENDERER) {
+        Exception cause = e.getRendererException();
+        if (cause instanceof DecoderInitializationException) {
+          // Special case for decoder initialization failures.
+          DecoderInitializationException decoderInitializationException =
+              (DecoderInitializationException) cause;
+          if (decoderInitializationException.decoderName == null) {
+            if (decoderInitializationException.getCause() instanceof DecoderQueryException) {
+              errorString = getString(R.string.error_querying_decoders);
+            } else if (decoderInitializationException.secureDecoderRequired) {
+              errorString =
+                  getString(
+                      R.string.error_no_secure_decoder, decoderInitializationException.mimeType);
+            } else {
+              errorString =
+                  getString(R.string.error_no_decoder, decoderInitializationException.mimeType);
+            }
+          } else {
+            errorString =
+                getString(
+                    R.string.error_instantiating_decoder,
+                    decoderInitializationException.decoderName);
+          }
+        }
+      }
+      return Pair.create(0, errorString);
+    }
   }
 
 }

demos/main/src/main/res/values/strings.xml

@@ -19,6 +19,8 @@
 
   <string name="unexpected_intent_action">Unexpected intent action: <xliff:g id="action">%1$s</xliff:g></string>
 
+  <string name="error_generic">Playback failed</string>
+
   <string name="error_unrecognized_abr_algorithm">Unrecognized ABR algorithm</string>
 
   <string name="error_drm_not_supported">Protected content not supported on API levels below 18</string>

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

@@ -53,7 +53,7 @@ public final class LeanbackPlayerAdapter extends PlayerAdapter {
 
   private @Nullable PlaybackPreparer playbackPreparer;
   private ControlDispatcher controlDispatcher;
-  private ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider;
+  private @Nullable ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider;
   private SurfaceHolderGlueHost surfaceHolderGlueHost;
   private boolean hasSurface;
   private boolean lastNotifiedPreparedState;
@@ -110,7 +110,7 @@ public final class LeanbackPlayerAdapter extends PlayerAdapter {
    * @param errorMessageProvider The {@link ErrorMessageProvider}.
    */
   public void setErrorMessageProvider(
-      ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider) {
+      @Nullable ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider) {
     this.errorMessageProvider = errorMessageProvider;
   }
 

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

@@ -334,7 +334,7 @@ public final class MediaSessionConnector {
   private Player player;
   private CustomActionProvider[] customActionProviders;
   private Map<String, CustomActionProvider> customActionMap;
-  private ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider;
+  private @Nullable ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider;
   private PlaybackPreparer playbackPreparer;
   private QueueNavigator queueNavigator;
   private QueueEditor queueEditor;
@@ -436,12 +436,12 @@ public final class MediaSessionConnector {
   }
 
   /**
-   * Sets the {@link ErrorMessageProvider}.
+   * Sets the optional {@link ErrorMessageProvider}.
    *
    * @param errorMessageProvider The error message provider.
    */
   public void setErrorMessageProvider(
-      ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider) {
+      @Nullable ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider) {
     if (this.errorMessageProvider != errorMessageProvider) {
       this.errorMessageProvider = errorMessageProvider;
       updateMediaSessionPlaybackState();

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

@@ -36,9 +36,11 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.FrameLayout;
 import android.widget.ImageView;
+import android.widget.TextView;
 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;
 import com.google.android.exoplayer2.Player.DiscontinuityReason;
@@ -51,6 +53,7 @@ import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.ui.AspectRatioFrameLayout.ResizeMode;
 import com.google.android.exoplayer2.util.Assertions;
+import com.google.android.exoplayer2.util.ErrorMessageProvider;
 import com.google.android.exoplayer2.util.RepeatModeUtil;
 import com.google.android.exoplayer2.util.Util;
 import com.google.android.exoplayer2.video.VideoListener;
@@ -102,6 +105,12 @@ import java.util.List;
  *         <li>Corresponding method: {@link #setControllerHideDuringAds(boolean)}
  *         <li>Default: {@code true}
  *       </ul>
+ *   <li><b>{@code show_buffering}</b> - Whether the buffering spinner is displayed when the player
+ *       is buffering.
+ *       <ul>
+ *         <li>Corresponding method: {@link #setShowBuffering(boolean)}
+ *         <li>Default: {@code false}
+ *       </ul>
  *   <li><b>{@code resize_mode}</b> - Controls how video and album art is resized within the view.
  *       Valid values are {@code fit}, {@code fixed_width}, {@code fixed_height} and {@code fill}.
  *       <ul>
@@ -164,6 +173,11 @@ import java.util.List;
  *       <ul>
  *         <li>Type: {@link View}
  *       </ul>
+ *   <li><b>{@code exo_buffering}</b> - A view that's made visible when the player is buffering.
+ *       This view typically displays a buffering spinner or animation.
+ *       <ul>
+ *         <li>Type: {@link View}
+ *       </ul>
  *   <li><b>{@code exo_subtitles}</b> - Displays subtitles.
  *       <ul>
  *         <li>Type: {@link SubtitleView}
@@ -172,6 +186,10 @@ import java.util.List;
  *       <ul>
  *         <li>Type: {@link ImageView}
  *       </ul>
+ *   <li><b>{@code exo_error_message}</b> - Displays an error message to the user if playback fails.
+ *       <ul>
+ *         <li>Type: {@link TextView}
+ *       </ul>
  *   <li><b>{@code exo_controller_placeholder}</b> - A placeholder that's replaced with the inflated
  *       {@link PlayerControlView}. Ignored if an {@code exo_controller} view exists.
  *       <ul>
@@ -213,6 +231,8 @@ public class PlayerView extends FrameLayout {
   private final View surfaceView;
   private final ImageView artworkView;
   private final SubtitleView subtitleView;
+  private final @Nullable View bufferingView;
+  private final @Nullable TextView errorMessageView;
   private final PlayerControlView controller;
   private final ComponentListener componentListener;
   private final FrameLayout overlayFrameLayout;
@@ -221,6 +241,9 @@ public class PlayerView extends FrameLayout {
   private boolean useController;
   private boolean useArtwork;
   private Bitmap defaultArtwork;
+  private boolean showBuffering;
+  private @Nullable ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider;
+  private @Nullable CharSequence customErrorMessage;
   private int controllerShowTimeoutMs;
   private boolean controllerAutoShow;
   private boolean controllerHideDuringAds;
@@ -244,6 +267,8 @@ public class PlayerView extends FrameLayout {
       surfaceView = null;
       artworkView = null;
       subtitleView = null;
+      bufferingView = null;
+      errorMessageView = null;
       controller = null;
       componentListener = null;
       overlayFrameLayout = null;
@@ -269,6 +294,7 @@ public class PlayerView extends FrameLayout {
     boolean controllerHideOnTouch = true;
     boolean controllerAutoShow = true;
     boolean controllerHideDuringAds = true;
+    boolean showBuffering = false;
     if (attrs != null) {
       TypedArray a = context.getTheme().obtainStyledAttributes(attrs, R.styleable.PlayerView, 0, 0);
       try {
@@ -286,6 +312,7 @@ public class PlayerView extends FrameLayout {
         controllerHideOnTouch =
             a.getBoolean(R.styleable.PlayerView_hide_on_touch, controllerHideOnTouch);
         controllerAutoShow = a.getBoolean(R.styleable.PlayerView_auto_show, controllerAutoShow);
+        showBuffering = a.getBoolean(R.styleable.PlayerView_show_buffering, showBuffering);
         controllerHideDuringAds =
             a.getBoolean(R.styleable.PlayerView_hide_during_ads, controllerHideDuringAds);
       } finally {
@@ -341,6 +368,19 @@ public class PlayerView extends FrameLayout {
       subtitleView.setUserDefaultTextSize();
     }
 
+    // Buffering view.
+    bufferingView = findViewById(R.id.exo_buffering);
+    if (bufferingView != null) {
+      bufferingView.setVisibility(View.GONE);
+    }
+    this.showBuffering = showBuffering;
+
+    // Error message view.
+    errorMessageView = findViewById(R.id.exo_error_message);
+    if (errorMessageView != null) {
+      errorMessageView.setVisibility(View.GONE);
+    }
+
     // Playback control view.
     PlayerControlView customController = findViewById(R.id.exo_controller);
     View controllerPlaceholder = findViewById(R.id.exo_controller_placeholder);
@@ -438,6 +478,8 @@ public class PlayerView extends FrameLayout {
     if (subtitleView != null) {
       subtitleView.setCues(null);
     }
+    updateBuffering();
+    updateErrorMessage();
     if (player != null) {
       Player.VideoComponent newVideoComponent = player.getVideoComponent();
       if (newVideoComponent != null) {
@@ -558,6 +600,44 @@ public class PlayerView extends FrameLayout {
     }
   }
 
+  /**
+   * Sets whether a buffering spinner is displayed when the player is in the buffering state. The
+   * buffering spinner is not displayed by default.
+   *
+   * @param showBuffering Whether the buffering icon is displayer
+   */
+  public void setShowBuffering(boolean showBuffering) {
+    if (this.showBuffering != showBuffering) {
+      this.showBuffering = showBuffering;
+      updateBuffering();
+    }
+  }
+
+  /**
+   * Sets the optional {@link ErrorMessageProvider}.
+   *
+   * @param errorMessageProvider The error message provider.
+   */
+  public void setErrorMessageProvider(
+      @Nullable ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider) {
+    if (this.errorMessageProvider != errorMessageProvider) {
+      this.errorMessageProvider = errorMessageProvider;
+      updateErrorMessage();
+    }
+  }
+
+  /**
+   * Sets a custom error message to be displayed by the view. The error message will be displayed
+   * permanently, unless it is cleared by passing {@code null} to this method.
+   *
+   * @param message The message to display, or {@code null} to clear a previously set message.
+   */
+  public void setCustomErrorMessage(@Nullable CharSequence message) {
+    Assertions.checkState(errorMessageView != null);
+    customErrorMessage = message;
+    updateErrorMessage();
+  }
+
   @Override
   public boolean dispatchKeyEvent(KeyEvent event) {
     if (player != null && player.isPlayingAd()) {
@@ -954,6 +1034,40 @@ public class PlayerView extends FrameLayout {
     }
   }
 
+  private void updateBuffering() {
+    if (bufferingView != null) {
+      boolean showBufferingSpinner =
+          showBuffering
+              && player != null
+              && player.getPlaybackState() == Player.STATE_BUFFERING
+              && player.getPlayWhenReady();
+      bufferingView.setVisibility(showBufferingSpinner ? View.VISIBLE : View.GONE);
+    }
+  }
+
+  private void updateErrorMessage() {
+    if (errorMessageView != null) {
+      if (customErrorMessage != null) {
+        errorMessageView.setText(customErrorMessage);
+        errorMessageView.setVisibility(View.VISIBLE);
+        return;
+      }
+      ExoPlaybackException error = null;
+      if (player != null
+          && player.getPlaybackState() == Player.STATE_IDLE
+          && errorMessageProvider != null) {
+        error = player.getPlaybackError();
+      }
+      if (error != null) {
+        CharSequence errorMessage = errorMessageProvider.getErrorMessage(error).second;
+        errorMessageView.setText(errorMessage);
+        errorMessageView.setVisibility(View.VISIBLE);
+      } else {
+        errorMessageView.setVisibility(View.GONE);
+      }
+    }
+  }
+
   @TargetApi(23)
   private static void configureEditModeLogoV23(Resources resources, ImageView logo) {
     logo.setImageDrawable(resources.getDrawable(R.drawable.exo_edit_mode_logo, null));
@@ -1070,6 +1184,8 @@ public class PlayerView extends FrameLayout {
 
     @Override
     public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
+      updateBuffering();
+      updateErrorMessage();
       if (isPlayingAd() && controllerHideDuringAds) {
         hideController();
       } else {

library/ui/src/main/res/layout/exo_simple_player_view.xml

@@ -36,6 +36,20 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent"/>
 
+    <ProgressBar android:id="@id/exo_buffering"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:indeterminate="true"
+        android:layout_gravity="center"/>
+
+    <TextView android:id="@id/exo_error_message"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:layout_gravity="center"
+        android:gravity="center"
+        android:background="@color/exo_error_message_background_color"
+        android:padding="16dp"/>
+
   </com.google.android.exoplayer2.ui.AspectRatioFrameLayout>
 
   <FrameLayout android:id="@id/exo_overlay"

library/ui/src/main/res/values/attrs.xml

@@ -50,6 +50,7 @@
     <attr name="hide_on_touch" format="boolean"/>
     <attr name="hide_during_ads" format="boolean"/>
     <attr name="auto_show" format="boolean"/>
+    <attr name="show_buffering" format="boolean"/>
     <attr name="resize_mode"/>
     <attr name="surface_type"/>
     <attr name="player_layout_id"/>

library/ui/src/main/res/values/constants.xml

@@ -18,6 +18,7 @@
   <dimen name="exo_media_button_width">71dp</dimen>
   <dimen name="exo_media_button_height">52dp</dimen>
 
+  <color name="exo_error_message_background_color">#AA000000</color>
   <color name="exo_edit_mode_background_color">#FFF4F3F0</color>
 
 </resources>

library/ui/src/main/res/values/ids.xml

@@ -33,5 +33,7 @@
   <item name="exo_duration" type="id"/>
   <item name="exo_position" type="id"/>
   <item name="exo_progress" type="id"/>
+  <item name="exo_buffering" type="id"/>
+  <item name="exo_error_message" type="id"/>
 
 </resources>