Add force SmartDark dev setting

Bug: 118348733
Test: toggled it
Change-Id: I43b8ddaada9f8fc0a2a1fb4144fd4a53141bdb2e

res/values/strings.xml

@@ -10281,6 +10281,11 @@
     <!-- UI debug setting: force desktop mode summary [CHAR LIMIT=NONE] -->
     <string name="force_desktop_mode_summary">Force experimental desktop mode on secondary displays</string>
 
+    <!-- UI debug setting: Force enable "smart dark" UI rendering feature [CHAR LIMIT=25] -->
+    <string name="hwui_force_dark_title">Force-enable SmartDark</string>
+    <!-- UI debug setting: Force enable "smart dark" UI rendering feature summary [CHAR LIMIT=50] -->
+    <string name="hwui_force_dark_summary">Forces the SmartDark feature to be always-on</string>
+
     <!-- Title for the top level Privacy Settings [CHAR LIMIT=30]-->
     <string name="privacy_dashboard_title">Privacy</string>
     <!-- Summary for the top level Privacy Settings [CHAR LIMIT=NONE]-->

res/xml/development_settings.xml

@@ -402,6 +402,11 @@
             android:entries="@array/show_non_rect_clip_entries"
             android:entryValues="@array/show_non_rect_clip_values" />
 
+        <SwitchPreference
+            android:key="hwui_force_dark"
+            android:title="@string/hwui_force_dark_title"
+            android:summary="@string/hwui_force_dark_summary" />
+
         <SwitchPreference
             android:key="force_msaa"
             android:title="@string/force_msaa"

src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java

@@ -445,6 +445,7 @@ public class DevelopmentSettingsDashboardFragment extends RestrictedDashboardFra
         controllers.add(new HardwareLayersUpdatesPreferenceController(context));
         controllers.add(new DebugGpuOverdrawPreferenceController(context));
         controllers.add(new DebugNonRectClipOperationsPreferenceController(context));
+        controllers.add(new ForceDarkPreferenceController(context));
         controllers.add(new ForceMSAAPreferenceController(context));
         controllers.add(new HardwareOverlaysPreferenceController(context));
         controllers.add(new SimulateColorSpacePreferenceController(context));

src/com/android/settings/development/ForceDarkPreferenceController.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2018 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.development;
+
+import android.content.Context;
+import android.os.SystemProperties;
+import android.view.ThreadedRenderer;
+
+import androidx.preference.Preference;
+import androidx.preference.SwitchPreference;
+
+import com.android.settings.core.PreferenceControllerMixin;
+import com.android.settingslib.development.DeveloperOptionsPreferenceController;
+import com.android.settingslib.development.SystemPropPoker;
+
+public class ForceDarkPreferenceController extends DeveloperOptionsPreferenceController
+        implements Preference.OnPreferenceChangeListener, PreferenceControllerMixin {
+
+    private static final String HWUI_FORCE_DARK = "hwui_force_dark";
+
+    public ForceDarkPreferenceController(Context context) {
+        super(context);
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return HWUI_FORCE_DARK;
+    }
+
+    @Override
+    public boolean onPreferenceChange(Preference preference, Object newValue) {
+        final boolean isEnabled = (Boolean) newValue;
+        SystemProperties.set(ThreadedRenderer.DEBUG_FORCE_DARK,
+                isEnabled ? "true" : null);
+        SystemPropPoker.getInstance().poke();
+        return true;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        final boolean isEnabled = SystemProperties.getBoolean(
+                ThreadedRenderer.DEBUG_FORCE_DARK, false /* default */);
+        ((SwitchPreference) mPreference).setChecked(isEnabled);
+    }
+
+    @Override
+    protected void onDeveloperOptionsSwitchDisabled() {
+        super.onDeveloperOptionsSwitchDisabled();
+        SystemProperties.set(ThreadedRenderer.DEBUG_FORCE_DARK, null);
+        ((SwitchPreference) mPreference).setChecked(false);
+    }
+}

tests/robotests/src/com/android/settings/development/ForceDarkPreferenceControllerTest.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2018 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.development;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.os.SystemProperties;
+import android.view.ThreadedRenderer;
+
+import androidx.preference.PreferenceScreen;
+import androidx.preference.SwitchPreference;
+
+import com.android.settings.testutils.SettingsRobolectricTestRunner;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RuntimeEnvironment;
+
+@RunWith(SettingsRobolectricTestRunner.class)
+public class ForceDarkPreferenceControllerTest {
+
+    @Mock
+    private SwitchPreference mPreference;
+    @Mock
+    private PreferenceScreen mPreferenceScreen;
+
+    private Context mContext;
+    private ForceDarkPreferenceController mController;
+
+    @Before
+    public void setup() {
+        MockitoAnnotations.initMocks(this);
+        mContext = RuntimeEnvironment.application;
+        mController = new ForceDarkPreferenceController(mContext);
+        when(mPreferenceScreen.findPreference(mController.getPreferenceKey())).thenReturn(
+                mPreference);
+        mController.displayPreference(mPreferenceScreen);
+    }
+
+    @Test
+    public void onPreferenceChanged_settingEnabled_turnOnForceDark() {
+        mController.onPreferenceChange(mPreference, true /* new value */);
+
+        final boolean mode = SystemProperties
+            .getBoolean(ThreadedRenderer.DEBUG_FORCE_DARK, false /* default */);
+
+        assertThat(mode).isTrue();
+    }
+
+    @Test
+    public void onPreferenceChanged_settingDisabled_turnOffForceDark() {
+        mController.onPreferenceChange(mPreference, false /* new value */);
+
+        final boolean mode = SystemProperties
+            .getBoolean(ThreadedRenderer.DEBUG_FORCE_DARK, false /* default */);
+
+        assertThat(mode).isFalse();
+    }
+
+    @Test
+    public void updateState_settingEnabled_preferenceShouldBeChecked() {
+        SystemProperties.set(ThreadedRenderer.DEBUG_FORCE_DARK, Boolean.toString(true));
+        mController.updateState(mPreference);
+
+        verify(mPreference).setChecked(true);
+    }
+
+    @Test
+    public void updateState_settingDisabled_preferenceShouldNotBeChecked() {
+        SystemProperties
+            .set(ThreadedRenderer.DEBUG_FORCE_DARK, Boolean.toString(false));
+        mController.updateState(mPreference);
+
+        verify(mPreference).setChecked(false);
+    }
+
+    @Test
+    public void onDeveloperOptionsDisabled_shouldDisablePreference() {
+        mController.onDeveloperOptionsDisabled();
+
+        verify(mPreference).setEnabled(false);
+        verify(mPreference).setChecked(false);
+    }
+}