Automatically show closed captioning/hearing impaired text track

library/core/src/main/java/com/google/android/exoplayer2/trackselection/DefaultTrackSelector.java

@@ -432,6 +432,12 @@ public class DefaultTrackSelector extends MappingTrackSelector {
       return this;
     }
 
+    @Override
+    public ParametersBuilder setPreferredRoleFlags(int preferredRoleFlags) {
+      super.setPreferredRoleFlags(preferredRoleFlags);
+      return this;
+    }
+
     @Override
     public ParametersBuilder setSelectUndeterminedTextLanguage(
         boolean selectUndeterminedTextLanguage) {
@@ -642,6 +648,7 @@ public class DefaultTrackSelector extends MappingTrackSelector {
           allowAudioMixedSampleRateAdaptiveness,
           // Text
           preferredTextLanguage,
+          preferredRoleFlags,
           selectUndeterminedTextLanguage,
           disabledTextTrackSelectionFlags,
           // General
@@ -837,6 +844,7 @@ public class DefaultTrackSelector extends MappingTrackSelector {
           /* allowAudioMixedSampleRateAdaptiveness= */ false,
           // Text
           TrackSelectionParameters.DEFAULT.preferredTextLanguage,
+          TrackSelectionParameters.DEFAULT.preferredRoleFlags,
           TrackSelectionParameters.DEFAULT.selectUndeterminedTextLanguage,
           TrackSelectionParameters.DEFAULT.disabledTextTrackSelectionFlags,
           // General
@@ -869,6 +877,7 @@ public class DefaultTrackSelector extends MappingTrackSelector {
         boolean allowAudioMixedSampleRateAdaptiveness,
         // Text
         @Nullable String preferredTextLanguage,
+        int preferredRoleFlags,
         boolean selectUndeterminedTextLanguage,
         @C.SelectionFlags int disabledTextTrackSelectionFlags,
         // General
@@ -882,6 +891,7 @@ public class DefaultTrackSelector extends MappingTrackSelector {
       super(
           preferredAudioLanguage,
           preferredTextLanguage,
+          preferredRoleFlags,
           selectUndeterminedTextLanguage,
           disabledTextTrackSelectionFlags);
       // Video
@@ -2590,6 +2600,7 @@ public class DefaultTrackSelector extends MappingTrackSelector {
     private final boolean isDefault;
     private final boolean hasPreferredIsForcedFlag;
     private final int preferredLanguageScore;
+    private final int preferredRoleFlagsScore;
     private final int selectedAudioLanguageScore;
 
     public TextTrackScore(
@@ -2606,6 +2617,7 @@ public class DefaultTrackSelector extends MappingTrackSelector {
       preferredLanguageScore =
           getFormatLanguageScore(
               format, parameters.preferredTextLanguage, parameters.selectUndeterminedTextLanguage);
+      preferredRoleFlagsScore = format.roleFlags & parameters.preferredRoleFlags;
       // Prefer non-forced to forced if a preferred text language has been matched. Where both are
       // provided the non-forced track will usually contain the forced subtitles as a subset.
       // Otherwise, prefer a forced track.
@@ -2616,7 +2628,7 @@ public class DefaultTrackSelector extends MappingTrackSelector {
       selectedAudioLanguageScore =
           getFormatLanguageScore(format, selectedAudioLanguage, selectedAudioLanguageUndetermined);
       isWithinConstraints =
-          preferredLanguageScore > 0 || isDefault || (isForced && selectedAudioLanguageScore > 0);
+          (preferredLanguageScore > 0 || (parameters.preferredTextLanguage == null && selectedAudioLanguageScore > 0 && preferredRoleFlagsScore > 0)) || isDefault || (isForced && selectedAudioLanguageScore > 0);
     }
 
     /**
@@ -2634,6 +2646,9 @@ public class DefaultTrackSelector extends MappingTrackSelector {
       if (this.preferredLanguageScore != other.preferredLanguageScore) {
         return compareInts(this.preferredLanguageScore, other.preferredLanguageScore);
       }
+      if (this.preferredRoleFlagsScore != other.preferredRoleFlagsScore) {
+        return compareInts(this.preferredRoleFlagsScore, other.preferredRoleFlagsScore);
+      }
       if (this.isDefault != other.isDefault) {
         return this.isDefault ? 1 : -1;
       }

library/core/src/main/java/com/google/android/exoplayer2/trackselection/TrackSelectionParameters.java

@@ -33,6 +33,7 @@ public class TrackSelectionParameters implements Parcelable {
 
     @Nullable /* package */ String preferredAudioLanguage;
     @Nullable /* package */ String preferredTextLanguage;
+    @C.RoleFlags /* package */ int preferredRoleFlags;
     /* package */ boolean selectUndeterminedTextLanguage;
     @C.SelectionFlags /* package */ int disabledTextTrackSelectionFlags;
 
@@ -48,6 +49,7 @@ public class TrackSelectionParameters implements Parcelable {
     /* package */ Builder(TrackSelectionParameters initialValues) {
       preferredAudioLanguage = initialValues.preferredAudioLanguage;
       preferredTextLanguage = initialValues.preferredTextLanguage;
+      preferredRoleFlags = initialValues.preferredRoleFlags;
       selectUndeterminedTextLanguage = initialValues.selectUndeterminedTextLanguage;
       disabledTextTrackSelectionFlags = initialValues.disabledTextTrackSelectionFlags;
     }
@@ -74,6 +76,17 @@ public class TrackSelectionParameters implements Parcelable {
       return this;
     }
 
+    /**
+     * See {@link TrackSelectionParameters#preferredRoleFlags}.
+     *
+     * @param preferredRoleFlags Preferred role flags.
+     * @return This builder.
+     */
+    public Builder setPreferredRoleFlags(int preferredRoleFlags) {
+      this.preferredRoleFlags = preferredRoleFlags;
+      return this;
+    }
+
     /**
      * See {@link TrackSelectionParameters#selectUndeterminedTextLanguage}.
      *
@@ -102,6 +115,7 @@ public class TrackSelectionParameters implements Parcelable {
           preferredAudioLanguage,
           // Text
           preferredTextLanguage,
+          preferredRoleFlags,
           selectUndeterminedTextLanguage,
           disabledTextTrackSelectionFlags);
     }
@@ -121,6 +135,11 @@ public class TrackSelectionParameters implements Parcelable {
    * the default track if there is one, or no track otherwise. The default value is {@code null}.
    */
   @Nullable public final String preferredTextLanguage;
+  /**
+   * The preferred role flags for text tracks. {@code 0} selects
+   * the default track if there is one, or no track otherwise. The default value is {@code 0}.
+   */
+  @Nullable public final int preferredRoleFlags;
   /**
    * Whether a text track with undetermined language should be selected if no track with {@link
    * #preferredTextLanguage} is available, or if {@link #preferredTextLanguage} is unset. The
@@ -138,6 +157,7 @@ public class TrackSelectionParameters implements Parcelable {
         /* preferredAudioLanguage= */ null,
         // Text
         /* preferredTextLanguage= */ null,
+        /* preferredRoleFlags= */ 0,
         /* selectUndeterminedTextLanguage= */ false,
         /* disabledTextTrackSelectionFlags= */ 0);
   }
@@ -145,12 +165,14 @@ public class TrackSelectionParameters implements Parcelable {
   /* package */ TrackSelectionParameters(
       @Nullable String preferredAudioLanguage,
       @Nullable String preferredTextLanguage,
+      int preferredRoleFlags,
       boolean selectUndeterminedTextLanguage,
       @C.SelectionFlags int disabledTextTrackSelectionFlags) {
     // Audio
     this.preferredAudioLanguage = Util.normalizeLanguageCode(preferredAudioLanguage);
     // Text
     this.preferredTextLanguage = Util.normalizeLanguageCode(preferredTextLanguage);
+    this.preferredRoleFlags = preferredRoleFlags;
     this.selectUndeterminedTextLanguage = selectUndeterminedTextLanguage;
     this.disabledTextTrackSelectionFlags = disabledTextTrackSelectionFlags;
   }
@@ -158,6 +180,7 @@ public class TrackSelectionParameters implements Parcelable {
   /* package */ TrackSelectionParameters(Parcel in) {
     this.preferredAudioLanguage = in.readString();
     this.preferredTextLanguage = in.readString();
+    this.preferredRoleFlags = in.readInt();
     this.selectUndeterminedTextLanguage = Util.readBoolean(in);
     this.disabledTextTrackSelectionFlags = in.readInt();
   }
@@ -179,6 +202,7 @@ public class TrackSelectionParameters implements Parcelable {
     TrackSelectionParameters other = (TrackSelectionParameters) obj;
     return TextUtils.equals(preferredAudioLanguage, other.preferredAudioLanguage)
         && TextUtils.equals(preferredTextLanguage, other.preferredTextLanguage)
+        && preferredRoleFlags == other.preferredRoleFlags
         && selectUndeterminedTextLanguage == other.selectUndeterminedTextLanguage
         && disabledTextTrackSelectionFlags == other.disabledTextTrackSelectionFlags;
   }
@@ -188,6 +212,7 @@ public class TrackSelectionParameters implements Parcelable {
     int result = 1;
     result = 31 * result + (preferredAudioLanguage == null ? 0 : preferredAudioLanguage.hashCode());
     result = 31 * result + (preferredTextLanguage == null ? 0 : preferredTextLanguage.hashCode());
+    result = 31 * result + (preferredRoleFlags);
     result = 31 * result + (selectUndeterminedTextLanguage ? 1 : 0);
     result = 31 * result + disabledTextTrackSelectionFlags;
     return result;
@@ -204,6 +229,7 @@ public class TrackSelectionParameters implements Parcelable {
   public void writeToParcel(Parcel dest, int flags) {
     dest.writeString(preferredAudioLanguage);
     dest.writeString(preferredTextLanguage);
+    dest.writeInt(preferredRoleFlags);
     Util.writeBoolean(dest, selectUndeterminedTextLanguage);
     dest.writeInt(disabledTextTrackSelectionFlags);
   }