Handle recreation of TrackSelectionView instances.

TrackSelectionView requires an initialization with a call to init(...).
That's why we shouldn't let the view retain its view hierarchy automatically
as the views won't be backed by data if restored. Instead add a listener
which lets the containing activity/fragment save and restore the state if
needed.

PiperOrigin-RevId: 234152491

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

@@ -261,15 +261,17 @@ public final class TrackSelectionDialog extends DialogFragment {
   }
 
   /** Fragment to show a track seleciton in tab of the track selection dialog. */
-  public static final class TrackSelectionViewFragment extends Fragment {
+  public static final class TrackSelectionViewFragment extends Fragment
+      implements TrackSelectionView.TrackSelectionListener {
 
     private MappedTrackInfo mappedTrackInfo;
     private int rendererIndex;
-    private boolean initialIsDisabled;
-    @Nullable private SelectionOverride initialOverride;
     private boolean allowAdaptiveSelections;
     private boolean allowMultipleOverrides;
 
+    private boolean isDisabled;
+    private List<SelectionOverride> overrides;
+
     /* package */ TrackSelectionView trackSelectionView;
 
     public void init(
@@ -281,8 +283,11 @@ public final class TrackSelectionDialog extends DialogFragment {
         boolean allowMultipleOverrides) {
       this.mappedTrackInfo = mappedTrackInfo;
       this.rendererIndex = rendererIndex;
-      this.initialIsDisabled = initialIsDisabled;
-      this.initialOverride = initialOverride;
+      this.isDisabled = initialIsDisabled;
+      this.overrides =
+          initialOverride == null
+              ? Collections.emptyList()
+              : Collections.singletonList(initialOverride);
       this.allowAdaptiveSelections = allowAdaptiveSelections;
       this.allowMultipleOverrides = allowMultipleOverrides;
     }
@@ -301,13 +306,14 @@ public final class TrackSelectionDialog extends DialogFragment {
       trackSelectionView.setAllowMultipleOverrides(allowMultipleOverrides);
       trackSelectionView.setAllowAdaptiveSelections(allowAdaptiveSelections);
       trackSelectionView.init(
-          mappedTrackInfo,
-          rendererIndex,
-          initialIsDisabled,
-          initialOverride == null
-              ? Collections.emptyList()
-              : Collections.singletonList(initialOverride));
+          mappedTrackInfo, rendererIndex, isDisabled, overrides, /* listener= */ this);
       return rootView;
     }
+
+    @Override
+    public void onTrackSelectionChanged(boolean isDisabled, List<SelectionOverride> overrides) {
+      this.isDisabled = isDisabled;
+      this.overrides = overrides;
+    }
   }
 }

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

@@ -219,7 +219,7 @@ public final class TrackSelectionDialogBuilder {
     if (trackNameProvider != null) {
       selectionView.setTrackNameProvider(trackNameProvider);
     }
-    selectionView.init(mappedTrackInfo, rendererIndex, isDisabled, overrides);
+    selectionView.init(mappedTrackInfo, rendererIndex, isDisabled, overrides, /* listener= */ null);
     Dialog.OnClickListener okClickListener =
         (dialog, which) ->
             callback.onTracksSelected(selectionView.getIsDisabled(), selectionView.getOverrides());

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

@@ -41,6 +41,18 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 /** A view for making track selections. */
 public class TrackSelectionView extends LinearLayout {
 
+  /** Listener for changes to the selected tracks. */
+  public interface TrackSelectionListener {
+
+    /**
+     * Called when the selected tracks changed.
+     *
+     * @param isDisabled Whether the renderer is disabled.
+     * @param overrides List of selected track selection overrides for the renderer.
+     */
+    void onTrackSelectionChanged(boolean isDisabled, List<SelectionOverride> overrides);
+  }
+
   private final int selectableItemBackgroundResourceId;
   private final LayoutInflater inflater;
   private final CheckedTextView disableView;
@@ -54,10 +66,11 @@ public class TrackSelectionView extends LinearLayout {
   private TrackNameProvider trackNameProvider;
   private CheckedTextView[][] trackViews;
 
-  private @MonotonicNonNull MappedTrackInfo mappedTrackInfo;
+  @MonotonicNonNull private MappedTrackInfo mappedTrackInfo;
   private int rendererIndex;
   private TrackGroupArray trackGroups;
   private boolean isDisabled;
+  @Nullable private TrackSelectionListener listener;
 
   /** Creates a track selection view. */
   public TrackSelectionView(Context context) {
@@ -76,6 +89,9 @@ public class TrackSelectionView extends LinearLayout {
     super(context, attrs, defStyleAttr);
     overrides = new SparseArray<>();
 
+    // Don't save view hierarchy as it needs to be reinitialized with a call to init.
+    setSaveFromParentEnabled(false);
+
     TypedArray attributeArray =
         context
             .getTheme()
@@ -177,15 +193,18 @@ public class TrackSelectionView extends LinearLayout {
    * @param overrides List of initial overrides to be shown for this renderer. There must be at most
    *     one override for each track group. If {@link #setAllowMultipleOverrides(boolean)} hasn't
    *     been set to {@code true}, only the first override is used.
+   * @param listener An optional listener for track selection updates.
    */
   public void init(
       MappedTrackInfo mappedTrackInfo,
       int rendererIndex,
       boolean isDisabled,
-      List<SelectionOverride> overrides) {
+      List<SelectionOverride> overrides,
+      @Nullable TrackSelectionListener listener) {
     this.mappedTrackInfo = mappedTrackInfo;
     this.rendererIndex = rendererIndex;
     this.isDisabled = isDisabled;
+    this.listener = listener;
     int maxOverrides = allowMultipleOverrides ? overrides.size() : Math.min(overrides.size(), 1);
     for (int i = 0; i < maxOverrides; i++) {
       SelectionOverride override = overrides.get(i);
@@ -291,6 +310,9 @@ public class TrackSelectionView extends LinearLayout {
       onTrackViewClicked(view);
     }
     updateViewStates();
+    if (listener != null) {
+      listener.onTrackSelectionChanged(getIsDisabled(), getOverrides());
+    }
   }
 
   private void onDisableViewClicked() {