New feature “Text and reading options” for SetupWizard, Wallpaper, and Settings (11/n).

- Create the display size LabeledSeekBarPreference and add the entry
1) It's integrated with the system display density configurations.
2) Create the new DisplaySizeData component to store the configurations related to the display size features.

Bug: 211503117
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DisplaySizeDataTest
Change-Id: If9e5cc6e2ff2c4f530634e39eb3cddd9e275bc03

res/xml/accessibility_text_reading_options.xml

@@ -31,6 +31,16 @@
         settings:iconStart="@drawable/ic_remove_24dp"
         settings:iconStartContentDescription="@string/font_size_make_smaller_desc"/>
 
+    <com.android.settings.widget.LabeledSeekBarPreference
+        android:key="display_size"
+        android:selectable="false"
+        android:summary="@string/screen_zoom_short_summary"
+        android:title="@string/screen_zoom_title"
+        settings:iconEnd="@drawable/ic_add_24dp"
+        settings:iconEndContentDescription="@string/screen_zoom_make_larger_desc"
+        settings:iconStart="@drawable/ic_remove_24dp"
+        settings:iconStartContentDescription="@string/screen_zoom_make_smaller_desc"/>
+
     <SwitchPreference
         android:key="toggle_force_bold_text"
         android:persistent="false"

src/com/android/settings/accessibility/DisplaySizeData.java

@@ -0,0 +1,65 @@
+/*
+ * 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.content.res.Resources;
+import android.view.Display;
+
+import com.android.settingslib.display.DisplayDensityConfiguration;
+import com.android.settingslib.display.DisplayDensityUtils;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.stream.Collectors;
+
+/**
+ * Data class for storing the configurations related to the display size.
+ */
+class DisplaySizeData extends PreviewSizeData<Integer> {
+    DisplaySizeData(Context context) {
+        super(context);
+
+        final DisplayDensityUtils density = new DisplayDensityUtils(getContext());
+        final int initialIndex = density.getCurrentIndex();
+        if (initialIndex < 0) {
+            // Failed to obtain default density, which means we failed to
+            // connect to the window manager service. Just use the current
+            // density and don't let the user change anything.
+            final Resources resources = getContext().getResources();
+            final int densityDpi = resources.getDisplayMetrics().densityDpi;
+            setDefaultValue(densityDpi);
+            setInitialIndex(0);
+            setValues(Collections.singletonList(densityDpi));
+        } else {
+            setDefaultValue(density.getDefaultDensity());
+            setInitialIndex(initialIndex);
+            setValues(Arrays.stream(density.getValues()).boxed().collect(Collectors.toList()));
+        }
+    }
+
+    @Override
+    void commit(int currentProgress) {
+        final int densityDpi = getValues().get(currentProgress);
+        if (densityDpi == getDefaultValue()) {
+            DisplayDensityConfiguration.clearForcedDisplayDensity(Display.DEFAULT_DISPLAY);
+        } else {
+            DisplayDensityConfiguration.setForcedDisplayDensity(Display.DEFAULT_DISPLAY,
+                    densityDpi);
+        }
+    }
+}

src/com/android/settings/accessibility/TextReadingPreferenceFragment.java

@@ -36,6 +36,7 @@ import java.util.List;
 public class TextReadingPreferenceFragment extends DashboardFragment {
     private static final String TAG = "TextReadingPreferenceFragment";
     private static final String FONT_SIZE_KEY = "font_size";
+    private static final String DISPLAY_SIZE_KEY = "display_size";
 
     @Override
     protected int getPreferenceScreenResId() {
@@ -56,8 +57,10 @@ public class TextReadingPreferenceFragment extends DashboardFragment {
     protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
         final List<AbstractPreferenceController> controllers = new ArrayList<>();
         final FontSizeData fontSizeData = new FontSizeData(context);
-
+        final DisplaySizeData displaySizeData = new DisplaySizeData(context);
         controllers.add(new PreviewSizeSeekBarController(context, FONT_SIZE_KEY, fontSizeData));
+        controllers.add(
+                new PreviewSizeSeekBarController(context, DISPLAY_SIZE_KEY, displaySizeData));
 
         return controllers;
     }

tests/robotests/src/com/android/settings/accessibility/DisplaySizeDataTest.java

@@ -0,0 +1,54 @@
+/*
+ * 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 static com.google.common.truth.Truth.assertThat;
+
+import android.content.Context;
+
+import androidx.test.core.app.ApplicationProvider;
+
+import org.junit.Before;
+import org.junit.Ignore;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+
+/**
+ * Tests for {@link DisplaySizeData}.
+ */
+@RunWith(RobolectricTestRunner.class)
+public class DisplaySizeDataTest {
+    private final Context mContext = ApplicationProvider.getApplicationContext();
+    private DisplaySizeData mDisplaySizeData;
+
+    @Before
+    public void setUp() {
+        mDisplaySizeData = new DisplaySizeData(mContext);
+    }
+
+    @Ignore("Ignore it since a NPE is happened in ShadowWindowManagerGlobal. (Ref. b/214161063)")
+    @Test
+    public void commit_success() {
+        final int progress = 4;
+
+        mDisplaySizeData.commit(progress);
+        final float density = mContext.getResources().getDisplayMetrics().density;
+
+        assertThat(density).isEqualTo(mDisplaySizeData.getValues().get(progress));
+    }
+}