-Added settings for managing caption font size.

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

@@ -51,6 +51,7 @@ import android.widget.Toast;
 
 import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.ui.AspectRatioFrameLayout;
+import com.google.android.exoplayer2.ui.SubtitleView;
 
 import org.schabi.newpipe.R;
 import org.schabi.newpipe.extractor.stream.StreamInfo;
@@ -337,8 +338,24 @@ public final class MainVideoPlayer extends Activity {
             channelTextView.setSelected(true);
 
             getRootView().setKeepScreenOn(true);
-            getSubtitleView().setFixedTextSize(TypedValue.COMPLEX_UNIT_PX,
+        }
-                    getCaptionSizePx(context));
+
+        @Override
+        protected void setupSubtitleView(@NonNull SubtitleView view,
+                                         @NonNull String captionSizeKey) {
+            final float captionRatio;
+            if (captionSizeKey.equals(getString(R.string.smaller_caption_size_key))) {
+                captionRatio = 22f;
+            } else if (captionSizeKey.equals(getString(R.string.larger_caption_size_key))) {
+                captionRatio = 18f;
+            } else {
+                captionRatio = 20f;
+            }
+
+            final DisplayMetrics metrics = context.getResources().getDisplayMetrics();
+            final int minimumLength = Math.min(metrics.heightPixels, metrics.widthPixels);
+            view.setFixedTextSize(TypedValue.COMPLEX_UNIT_PX,
+                    (float) minimumLength / captionRatio);
         }
 
         @Override
@@ -768,12 +785,6 @@ public final class MainVideoPlayer extends Activity {
             };
         }
 
-        private float getCaptionSizePx(@NonNull Context context) {
-            final DisplayMetrics metrics = context.getResources().getDisplayMetrics();
-            final int minimumLength = Math.min(metrics.heightPixels, metrics.widthPixels);
-            // todo: expose size control to users
-            return (float) minimumLength / 20f;
-        }
         ///////////////////////////////////////////////////////////////////////////
         // Getters
         ///////////////////////////////////////////////////////////////////////////

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

@@ -53,6 +53,7 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.PlaybackParameters;
 import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.ui.AspectRatioFrameLayout;
+import com.google.android.exoplayer2.ui.SubtitleView;
 
 import org.schabi.newpipe.BuildConfig;
 import org.schabi.newpipe.R;
@@ -391,6 +392,18 @@ public final class PopupVideoPlayer extends Service {
             rootView.addOnLayoutChangeListener(this);
         }
 
+        @Override
+        protected void setupSubtitleView(@NonNull SubtitleView view,
+                                         @NonNull String captionSizeKey) {
+            float captionRatio = SubtitleView.DEFAULT_TEXT_SIZE_FRACTION;
+            if (captionSizeKey.equals(getString(R.string.smaller_caption_size_key))) {
+                captionRatio *= 0.9;
+            } else if (captionSizeKey.equals(getString(R.string.larger_caption_size_key))) {
+                captionRatio *= 1.1;
+            }
+            view.setFractionalTextSize(captionRatio);
+        }
+
         @Override
         public void onLayoutChange(final View view, int left, int top, int right, int bottom,
                                    int oldLeft, int oldTop, int oldRight, int oldBottom) {

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

@@ -32,6 +32,7 @@ import android.graphics.PorterDuff;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Handler;
+import android.preference.PreferenceManager;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.content.ContextCompat;
@@ -183,7 +184,12 @@ public abstract class VideoPlayer extends BasePlayer
         this.bottomControlsRoot = rootView.findViewById(R.id.bottomControls);
         this.topControlsRoot = rootView.findViewById(R.id.topControls);
         this.qualityTextView = rootView.findViewById(R.id.qualityTextView);
+
         this.subtitleView = rootView.findViewById(R.id.subtitleView);
+        final String captionSizeKey = PreferenceManager.getDefaultSharedPreferences(context)
+                .getString(context.getString(R.string.caption_size_key),
+                        context.getString(R.string.caption_size_default));
+        setupSubtitleView(subtitleView, captionSizeKey);
 
         this.resizeView =  rootView.findViewById(R.id.resizeTextView);
         resizeView.setText(PlayerHelper.resizeTypeOf(context, aspectRatioFrameLayout.getResizeMode()));
@@ -204,6 +210,9 @@ public abstract class VideoPlayer extends BasePlayer
                 .getIndeterminateDrawable().setColorFilter(Color.WHITE, PorterDuff.Mode.MULTIPLY);
     }
 
+    protected abstract void setupSubtitleView(@NonNull SubtitleView view,
+                                              @NonNull String captionSizeKey);
+
     @Override
     public void initListeners() {
         super.initListeners();

app/src/main/res/values/settings_keys.xml

@@ -100,6 +100,25 @@
         <item>@string/black_theme_title</item>
     </string-array>
 
+    <!-- Caption Size -->
+    <string name="caption_size_key" translatable="false">caption_size_key</string>
+    <string name="caption_size_default" translatable="false">@string/normal_caption_size_key</string>
+
+    <string name="smaller_caption_size_key" translatable="false">smaller_caption_size</string>
+    <string name="normal_caption_size_key" translatable="false">normal_caption_size</string>
+    <string name="larger_caption_size_key" translatable="false">larger_caption_size</string>
+
+    <string-array name="caption_size_descriptions_list" translatable="false">
+        <item>@string/smaller_caption_font_size</item>
+        <item>@string/normal_caption_font_size</item>
+        <item>@string/larger_caption_font_size</item>
+    </string-array>
+    <string-array name="caption_size_values_list" translatable="false">
+        <item>@string/smaller_caption_size_key</item>
+        <item>@string/normal_caption_size_key</item>
+        <item>@string/larger_caption_size_key</item>
+    </string-array>
+
     <!-- Content & History -->
     <string name="show_search_suggestions_key" translatable="false">show_search_suggestions</string>
     <string name="show_play_with_kodi_key" translatable="false">show_play_with_kodi</string>

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

@@ -403,4 +403,9 @@
     <string name="resize_fill">FILL</string>
     <string name="resize_zoom">ZOOM</string>
 
+    <string name="caption_font_size_settings_title">Caption Font Size</string>
+    <string name="smaller_caption_font_size">Smaller Font</string>
+    <string name="normal_caption_font_size">Normal Font</string>
+    <string name="larger_caption_font_size">Larger Font</string>
+
 </resources>

app/src/main/res/xml/appearance_settings.xml

@@ -21,4 +21,12 @@
         android:key="@string/show_hold_to_append_key"
         android:title="@string/show_hold_to_append_title"
         android:summary="@string/show_hold_to_append_summary"/>
+
+    <ListPreference
+        android:defaultValue="@string/caption_size_default"
+        android:entries="@array/caption_size_descriptions_list"
+        android:entryValues="@array/caption_size_values_list"
+        android:key="@string/caption_size_key"
+        android:summary="%s"
+        android:title="@string/caption_font_size_settings_title"/>
 </PreferenceScreen>