Implemented Dark Mode for Android (flutter#25525) (flutter#7488)

ci/licenses_golden/licenses_flutter

@@ -423,9 +423,12 @@ FILE: ../../../flutter/shell/platform/android/io/flutter/app/FlutterFragmentActi
 FILE: ../../../flutter/shell/platform/android/io/flutter/app/FlutterPluginRegistry.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/FlutterEngine.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/FlutterJNI.java
+FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/dart/DartExecutor.java
+FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/dart/DartMessenger.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/dart/PlatformMessageHandler.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/renderer/FlutterRenderer.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/renderer/OnFirstFrameRenderedListener.java
+FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/SettingsChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/plugin/common/ActivityLifecycleListener.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/plugin/common/BasicMessageChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/plugin/common/BinaryCodec.java

lib/ui/hooks.dart

@@ -86,6 +86,7 @@ void _updateUserSettingsData(String jsonData) {
   }
   _updateTextScaleFactor(data['textScaleFactor'].toDouble());
   _updateAlwaysUse24HourFormat(data['alwaysUse24HourFormat']);
+  _updatePlatformBrightness(data['platformBrightness']);
 }
 
 void _updateTextScaleFactor(double textScaleFactor) {
@@ -97,6 +98,11 @@ void _updateAlwaysUse24HourFormat(bool alwaysUse24HourFormat) {
   window._alwaysUse24HourFormat = alwaysUse24HourFormat;
 }
 
+void _updatePlatformBrightness(String brightnessName) {
+  window._platformBrightness = brightnessName == 'dark' ? Brightness.dark : Brightness.light;
+  _invoke(window.onPlatformBrightnessChanged, window._onPlatformBrightnessChangedZone);
+}
+
 @pragma('vm:entry-point')
 // ignore: unused_element
 void _updateSemanticsEnabled(bool enabled) {

lib/ui/window.dart

@@ -590,6 +590,28 @@ class Window {
     _onTextScaleFactorChangedZone = Zone.current;
   }
 
+  /// The setting indicating the current brightness mode of the host platform.
+  /// If the platform has no preference, [platformBrightness] defaults to [Brightness.light].
+  Brightness get platformBrightness => _platformBrightness;
+  Brightness _platformBrightness = Brightness.light;
+
+  /// A callback that is invoked whenever [platformBrightness] changes value.
+  ///
+  /// The framework invokes this callback in the same zone in which the
+  /// callback was set.
+  ///
+  /// See also:
+  ///
+  ///  * [WidgetsBindingObserver], for a mechanism at the widgets layer to
+  ///    observe when this callback is invoked.
+  VoidCallback get onPlatformBrightnessChanged => _onPlatformBrightnessChanged;
+  VoidCallback _onPlatformBrightnessChanged;
+  Zone _onPlatformBrightnessChangedZone;
+  set onPlatformBrightnessChanged(VoidCallback callback) {
+    _onPlatformBrightnessChanged = callback;
+    _onPlatformBrightnessChangedZone = Zone.current;
+  }
+
   /// A callback that is invoked to notify the application that it is an
   /// appropriate time to provide a scene using the [SceneBuilder] API and the
   /// [render] method. When possible, this is driven by the hardware VSync

shell/platform/android/BUILD.gn

@@ -108,9 +108,12 @@ java_library("flutter_shell_java") {
     "io/flutter/app/FlutterPluginRegistry.java",
     "io/flutter/embedding/engine/FlutterEngine.java",
     "io/flutter/embedding/engine/FlutterJNI.java",
+    "io/flutter/embedding/engine/dart/DartExecutor.java",
+    "io/flutter/embedding/engine/dart/DartMessenger.java",
     "io/flutter/embedding/engine/dart/PlatformMessageHandler.java",
     "io/flutter/embedding/engine/renderer/FlutterRenderer.java",
     "io/flutter/embedding/engine/renderer/OnFirstFrameRenderedListener.java",
+    "io/flutter/embedding/engine/systemchannels/SettingsChannel.java",
     "io/flutter/plugin/common/ActivityLifecycleListener.java",
     "io/flutter/plugin/common/BasicMessageChannel.java",
     "io/flutter/plugin/common/BinaryCodec.java",

shell/platform/android/io/flutter/app/FlutterActivity.java

@@ -9,6 +9,8 @@
 import android.content.Intent;
 import android.content.res.Configuration;
 import android.os.Bundle;
+import android.support.annotation.NonNull;
+import android.util.Log;
 import io.flutter.app.FlutterActivityDelegate.ViewFactory;
 import io.flutter.plugin.common.PluginRegistry;
 import io.flutter.view.FlutterNativeView;
@@ -18,6 +20,8 @@
  * Base class for activities that use Flutter.
  */
 public class FlutterActivity extends Activity implements FlutterView.Provider, PluginRegistry, ViewFactory {
+    private static final String TAG = "FlutterActivity";
+
     private final FlutterActivityDelegate delegate = new FlutterActivityDelegate(this, this);
 
     // These aliases ensure that the methods we forward to the delegate adhere
@@ -129,7 +133,7 @@ protected void onPostResume() {
     }
 
     // @Override - added in API level 23
-    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
         eventDelegate.onRequestPermissionsResult(requestCode, permissions, grantResults);
     }
 

shell/platform/android/io/flutter/app/FlutterActivityDelegate.java

@@ -8,6 +8,7 @@
 import android.animation.AnimatorListenerAdapter;
 import android.app.Activity;
 import android.app.Application;
+import android.app.UiModeManager;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.ActivityInfo;
@@ -283,8 +284,7 @@ public void onLowMemory() {
     }
 
     @Override
-    public void onConfigurationChanged(Configuration newConfig) {
-    }
+    public void onConfigurationChanged(Configuration newConfig) {}
 
     private static String[] getArgsFromIntent(Intent intent) {
         // Before adding more entries to this list, consider that arbitrary
@@ -399,7 +399,7 @@ private Drawable getLaunchScreenDrawableFromActivityTheme() {
         if (!activity.getTheme().resolveAttribute(
             android.R.attr.windowBackground,
             typedValue,
-            true)) {;
+            true)) {
             return null;
         }
         if (typedValue.resourceId == 0) {