Refactor CaptionAppearanceFragment to improve maintainability (1/n)

Root cause: There is a bunch of different logic of preferences in CaptionAppearanceFragment. It’s hard to implement new features and hard to maintain and hard to be testable. Solution: Move out preview preference logic of CaptionAppearanceFragment into controllers to reduce the complexity of the relationship between preference and fragment. Bug: 197695932 Test: make RunSettingsRoboTests ROBOTEST_FILTER=com.android.settings.accessibility Change-Id: Ie8acdcb8659606ce3faf6d5532cc73ee19024725
2022-07-05 17:37:09 +08:00
parent 3d2e5a2447
commit 591e44bb99
7 changed files with 420 additions and 118 deletions
--- a/src/com/android/settings/accessibility/CaptionHelper.java
+++ b/src/com/android/settings/accessibility/CaptionHelper.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.accessibility;
+
+import android.content.Context;
+import android.view.View;
+import android.view.accessibility.CaptioningManager;
+
+import com.android.internal.widget.SubtitleView;
+import com.android.settings.R;
+import com.android.settingslib.accessibility.AccessibilityUtils;
+
+import com.google.common.annotations.VisibleForTesting;
+
+import java.util.Locale;
+
+/**
+ * Helper class for caption.
+ */
+public class CaptionHelper {
+
+    /* WebVtt specifies line height as 5.3% of the viewport height. */
+    @VisibleForTesting
+    static final float LINE_HEIGHT_RATIO = 0.0533f;
+
+    private final Context mContext;
+    private final CaptioningManager mCaptioningManager;
+
+    public CaptionHelper(Context context) {
+        mContext = context;
+        mCaptioningManager = context.getSystemService(CaptioningManager.class);
+    }
+
+    /**
+     * Updates font style of captioning properties for preview screen.
+     *
+     * @param previewText preview text
+     * @param previewWindow preview window
+     * @param styleId font style id
+     */
+    public void applyCaptionProperties(SubtitleView previewText, View previewWindow,
+            int styleId) {
+        previewText.setStyle(styleId);
+
+        final float fontScale = mCaptioningManager.getFontScale();
+        if (previewWindow != null) {
+            // Assume the viewport is clipped with a 16:9 aspect ratio.
+            final float virtualHeight = Math.max(9 * previewWindow.getWidth(),
+                    16 * previewWindow.getHeight()) / 16.0f;
+            previewText.setTextSize(virtualHeight * LINE_HEIGHT_RATIO * fontScale);
+        } else {
+            final float textSize = mContext.getResources().getDimension(
+                    R.dimen.caption_preview_text_size);
+            previewText.setTextSize(textSize * fontScale);
+        }
+
+        final Locale locale = mCaptioningManager.getLocale();
+        if (locale != null) {
+            final CharSequence localizedText = AccessibilityUtils.getTextForLocale(
+                    mContext, locale, R.string.captioning_preview_characters);
+            previewText.setText(localizedText);
+        } else {
+            previewText.setText(R.string.captioning_preview_characters);
+        }
+    }
+}