[sensor] Support v2 android embedder.

packages/sensors/android/build.gradle

@@ -45,3 +45,28 @@ android {
         disable 'InvalidPackage'
     }
 }
+
+afterEvaluate {
+    def containsEmbeddingDependencies = false
+    for (def configuration : configurations.all) {
+        for (def dependency : configuration.dependencies) {
+            if (dependency.group == 'io.flutter' &&
+                dependency.name.startsWith('flutter_embedding') &&
+                dependency.isTransitive())
+            {
+                containsEmbeddingDependencies = true
+                break
+            }
+        }
+    }
+    if (!containsEmbeddingDependencies) {
+        android {
+            dependencies {
+                def lifecycle_version = "2.1.0"
+
+                compileOnly "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"
+                compileOnly "androidx.lifecycle:lifecycle-runtime:$lifecycle_version"
+            }
+        }
+    }
+}

packages/sensors/android/gradle.properties

@@ -1 +1,4 @@
 org.gradle.jvmargs=-Xmx1536M
+android.enableR8=true
+android.useAndroidX=true
+android.enableJetifier=true

packages/sensors/android/src/main/java/io/flutter/plugins/sensors/SensorsPlugin.java

@@ -6,71 +6,63 @@
 
 import android.content.Context;
 import android.hardware.Sensor;
-import android.hardware.SensorEvent;
-import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;
+import io.flutter.embedding.engine.plugins.FlutterPlugin;
+import io.flutter.plugin.common.BinaryMessenger;
 import io.flutter.plugin.common.EventChannel;
 import io.flutter.plugin.common.PluginRegistry.Registrar;
 
 /** SensorsPlugin */
-public class SensorsPlugin implements EventChannel.StreamHandler {
+public class SensorsPlugin implements FlutterPlugin {
   private static final String ACCELEROMETER_CHANNEL_NAME =
       "plugins.flutter.io/sensors/accelerometer";
   private static final String GYROSCOPE_CHANNEL_NAME = "plugins.flutter.io/sensors/gyroscope";
   private static final String USER_ACCELEROMETER_CHANNEL_NAME =
       "plugins.flutter.io/sensors/user_accel";
 
+  private EventChannel accelerometerChannel;
+  private EventChannel userAccelChannel;
+  private EventChannel gyroscopeChannel;
+
   /** Plugin registration. */
   public static void registerWith(Registrar registrar) {
-    final EventChannel accelerometerChannel =
-        new EventChannel(registrar.messenger(), ACCELEROMETER_CHANNEL_NAME);
-    accelerometerChannel.setStreamHandler(
-        new SensorsPlugin(registrar.context(), Sensor.TYPE_ACCELEROMETER));
-
-    final EventChannel userAccelChannel =
-        new EventChannel(registrar.messenger(), USER_ACCELEROMETER_CHANNEL_NAME);
-    userAccelChannel.setStreamHandler(
-        new SensorsPlugin(registrar.context(), Sensor.TYPE_LINEAR_ACCELERATION));
-
-    final EventChannel gyroscopeChannel =
-        new EventChannel(registrar.messenger(), GYROSCOPE_CHANNEL_NAME);
-    gyroscopeChannel.setStreamHandler(
-        new SensorsPlugin(registrar.context(), Sensor.TYPE_GYROSCOPE));
-  }
-
-  private SensorEventListener sensorEventListener;
-  private final SensorManager sensorManager;
-  private final Sensor sensor;
-
-  private SensorsPlugin(Context context, int sensorType) {
-    sensorManager = (SensorManager) context.getSystemService(context.SENSOR_SERVICE);
-    sensor = sensorManager.getDefaultSensor(sensorType);
+    SensorsPlugin plugin = new SensorsPlugin();
+    plugin.setupEventChannels(registrar.context(), registrar.messenger());
   }
 
   @Override
-  public void onListen(Object arguments, EventChannel.EventSink events) {
-    sensorEventListener = createSensorEventListener(events);
-    sensorManager.registerListener(sensorEventListener, sensor, sensorManager.SENSOR_DELAY_NORMAL);
+  public void onAttachedToEngine(FlutterPluginBinding binding) {
+    Context context = binding.getApplicationContext();
+    setupEventChannels(context, binding.getFlutterEngine().getDartExecutor());
   }
 
   @Override
-  public void onCancel(Object arguments) {
-    sensorManager.unregisterListener(sensorEventListener);
+  public void onDetachedFromEngine(FlutterPluginBinding binding) {
+    accelerometerChannel.setStreamHandler(null);
+    userAccelChannel.setStreamHandler(null);
+    gyroscopeChannel.setStreamHandler(null);
   }
 
-  SensorEventListener createSensorEventListener(final EventChannel.EventSink events) {
-    return new SensorEventListener() {
-      @Override
-      public void onAccuracyChanged(Sensor sensor, int accuracy) {}
+  private void setupEventChannels(Context context, BinaryMessenger messenger) {
+    accelerometerChannel = new EventChannel(messenger, ACCELEROMETER_CHANNEL_NAME);
+    final StreamHandlerImpl accelerationStreamHandler =
+        new StreamHandlerImpl(
+            (SensorManager) context.getSystemService(context.SENSOR_SERVICE),
+            Sensor.TYPE_ACCELEROMETER);
+    accelerometerChannel.setStreamHandler(accelerationStreamHandler);
+
+    userAccelChannel = new EventChannel(messenger, USER_ACCELEROMETER_CHANNEL_NAME);
+    final StreamHandlerImpl linearAccelerationStreamHandler =
+        new StreamHandlerImpl(
+            (SensorManager) context.getSystemService(context.SENSOR_SERVICE),
+            Sensor.TYPE_LINEAR_ACCELERATION);
+    userAccelChannel.setStreamHandler(linearAccelerationStreamHandler);
 
-      @Override
-      public void onSensorChanged(SensorEvent event) {
-        double[] sensorValues = new double[event.values.length];
-        for (int i = 0; i < event.values.length; i++) {
-          sensorValues[i] = event.values[i];
-        }
-        events.success(sensorValues);
-      }
-    };
+    gyroscopeChannel = new EventChannel(messenger, GYROSCOPE_CHANNEL_NAME);
+    final StreamHandlerImpl gyroScopeStreamHandler =
+        new StreamHandlerImpl(
+            (SensorManager) context.getSystemService(context.SENSOR_SERVICE),
+            Sensor.TYPE_GYROSCOPE);
+    gyroscopeChannel.setStreamHandler(gyroScopeStreamHandler);
   }
 }

packages/sensors/android/src/main/java/io/flutter/plugins/sensors/StreamHandlerImpl.java

@@ -0,0 +1,50 @@
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.sensors;
+
+import android.hardware.Sensor;
+import android.hardware.SensorEvent;
+import android.hardware.SensorEventListener;
+import android.hardware.SensorManager;
+import io.flutter.plugin.common.EventChannel;
+
+class StreamHandlerImpl implements EventChannel.StreamHandler {
+
+  private SensorEventListener sensorEventListener;
+  private final SensorManager sensorManager;
+  private final Sensor sensor;
+
+  StreamHandlerImpl(SensorManager sensorManager, int sensorType) {
+    this.sensorManager = sensorManager;
+    sensor = sensorManager.getDefaultSensor(sensorType);
+  }
+
+  @Override
+  public void onListen(Object arguments, EventChannel.EventSink events) {
+    sensorEventListener = createSensorEventListener(events);
+    sensorManager.registerListener(sensorEventListener, sensor, sensorManager.SENSOR_DELAY_NORMAL);
+  }
+
+  @Override
+  public void onCancel(Object arguments) {
+    sensorManager.unregisterListener(sensorEventListener);
+  }
+
+  SensorEventListener createSensorEventListener(final EventChannel.EventSink events) {
+    return new SensorEventListener() {
+      @Override
+      public void onAccuracyChanged(Sensor sensor, int accuracy) {}
+
+      @Override
+      public void onSensorChanged(SensorEvent event) {
+        double[] sensorValues = new double[event.values.length];
+        for (int i = 0; i < event.values.length; i++) {
+          sensorValues[i] = event.values[i];
+        }
+        events.success(sensorValues);
+      }
+    };
+  }
+}

packages/sensors/example/android/app/src/main/AndroidManifest.xml

@@ -4,12 +4,19 @@
     <uses-permission android:name="android.permission.INTERNET"/>
 
     <application android:name="io.flutter.app.FlutterApplication" android:label="sensors_example" android:icon="@mipmap/ic_launcher">
-        <activity android:name=".MainActivity"
+        <activity android:name=".EmbeddingV1Activity"
                   android:launchMode="singleTop"
                   android:theme="@android:style/Theme.Black.NoTitleBar"
                   android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection"
                   android:hardwareAccelerated="true"
                   android:windowSoftInputMode="adjustResize">
+        </activity>
+        <activity android:name=".MainActivity"
+            android:launchMode="singleTop"
+            android:theme="@android:style/Theme.Black.NoTitleBar"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>

packages/sensors/example/android/app/src/main/java/io/flutter/plugins/sensorsexample/EmbeddingV1Activity.java

@@ -0,0 +1,17 @@
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.sensorsexample;
+
+import android.os.Bundle;
+import io.flutter.app.FlutterActivity;
+import io.flutter.plugins.GeneratedPluginRegistrant;
+
+public class EmbeddingV1Activity extends FlutterActivity {
+  @Override
+  protected void onCreate(Bundle savedInstanceState) {
+    super.onCreate(savedInstanceState);
+    GeneratedPluginRegistrant.registerWith(this);
+  }
+}

packages/sensors/example/android/app/src/main/java/io/flutter/plugins/sensorsexample/MainActivity.java

@@ -1,13 +1,18 @@
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
 package io.flutter.plugins.sensorsexample;
 
-import android.os.Bundle;
-import io.flutter.app.FlutterActivity;
-import io.flutter.plugins.GeneratedPluginRegistrant;
+import io.flutter.embedding.android.FlutterActivity;
+import io.flutter.embedding.engine.FlutterEngine;
+import io.flutter.plugins.sensors.SensorsPlugin;
 
 public class MainActivity extends FlutterActivity {
+
   @Override
-  protected void onCreate(Bundle savedInstanceState) {
-    super.onCreate(savedInstanceState);
-    GeneratedPluginRegistrant.registerWith(this);
+  public void configureFlutterEngine(FlutterEngine flutterEngine) {
+    super.configureFlutterEngine(flutterEngine);
+    flutterEngine.getPlugins().add(new SensorsPlugin());
   }
 }

packages/sensors/example/android/gradle.properties

@@ -1 +1,4 @@
 org.gradle.jvmargs=-Xmx1536M
+android.enableR8=true
+android.useAndroidX=true
+android.enableJetifier=true