MediaSession show media controls on Android

support/android/apk/servoapp/src/main/java/org/mozilla/servo/MainActivity.java

@@ -7,9 +7,16 @@ package org.mozilla.servo;
 
 import android.app.Activity;
 import android.app.AlertDialog;
+import android.app.PendingIntent;
+import android.app.Notification;
+import android.app.NotificationChannel;
+import android.app.NotificationManager;
+import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
+import android.content.IntentFilter;
 import android.net.Uri;
+import android.os.Build;
 import android.os.Bundle;
 import android.system.ErrnoException;
 import android.system.Os;
@@ -23,8 +30,6 @@ import android.widget.ProgressBar;
 import android.widget.TextView;
 import android.util.Log;
 
-//import org.mozilla.servo.MediaSessionCallback;
-
 import org.mozilla.servoview.ServoView;
 import org.mozilla.servoview.Servo;
 
@@ -32,7 +37,24 @@ import java.io.File;
 
 public class MainActivity extends Activity implements Servo.Client {
 
+    private class NotificationID {
+        private int lastID = 0;
+        public int getNext() {
+          lastID++;
+          return lastID;
+        }
+
+        public int get() {
+          return lastID;
+        }
+    }
+
     private static final String LOGTAG = "MainActivity";
+    private static final String MEDIA_CHANNEL_ID = "MediaNotificationChannel";
+    private static final String KEY_MEDIA_PAUSE = "org.mozilla.servoview.MainActivity.pause";
+    private static final String KEY_MEDIA_PREV = "org.mozilla.servoview.MainActivity.prev";
+    private static final String KEY_MEDIA_NEXT = "org.mozilla.servoview.MainActivity.next";
+    private static final String KEY_MEDIA_STOP = "org.mozilla.servoview.MainActivity.stop";
 
     ServoView mServoView;
     Button mBackButton;
@@ -43,7 +65,8 @@ public class MainActivity extends Activity implements Servo.Client {
     ProgressBar mProgressBar;
     TextView mIdleText;
     boolean mCanGoBack;
-    // MediaSession mSession;
+    NotificationID mNotificationID;
+    BroadcastReceiver mMediaSessionActionReceiver;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -86,6 +109,16 @@ public class MainActivity extends Activity implements Servo.Client {
           mServoView.loadUri(intent.getData());
         }
         setupUrlField();
+
+        mNotificationID = new NotificationID();
+        createMediaNotificationChannel();
+    }
+
+    @Override
+    protected void onDestroy() {
+      Log.d("SERVOMEDIA", "onDestroy");
+      super.onDestroy();
+      hideMediaSessionControls();
     }
 
     private void setupUrlField() {
@@ -206,6 +239,7 @@ public class MainActivity extends Activity implements Servo.Client {
         mServoView.onPause();
         super.onPause();
     }
+
     @Override
     public void onResume() {
         mServoView.onResume();
@@ -228,10 +262,98 @@ public class MainActivity extends Activity implements Servo.Client {
 
     @Override
     public void onMediaSessionPlaybackStateChange(int state) {
-      Log.d("SERVOMEDIA", "PLAYBACK STATE CHANGED");
+      Log.d("SERVOMEDIA", "PLAYBACK STATE CHANGED " + state);
+      if (state == 1 /* none */) {
+          hideMediaSessionControls();
+          return;
+      }
+      if (state == 2 /* playing */) {
+          showMediaSessionControls();
+          return;
+      }
     }
 
-/*    private void createMediaSession() {
-      mSession = new MediaSession(this, "ServoMediaSession");
-    }*/
+    private void createMediaNotificationChannel() {
+      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+          CharSequence name = getString(R.string.media_channel_name);
+          String description = getString(R.string.media_channel_description);
+          int importance = NotificationManager.IMPORTANCE_DEFAULT;
+          NotificationChannel channel = new NotificationChannel(MEDIA_CHANNEL_ID, name, importance);
+          channel.setDescription(description);
+          NotificationManager notificationManager = getSystemService(NotificationManager.class);
+          notificationManager.createNotificationChannel(channel);
+      }
+    }
+
+    private void showMediaSessionControls() {
+      Context context = getApplicationContext();
+
+      IntentFilter filter = new IntentFilter();
+      filter.addAction(KEY_MEDIA_PAUSE);
+      filter.addAction(KEY_MEDIA_STOP);
+      filter.addAction(KEY_MEDIA_PREV);
+      filter.addAction(KEY_MEDIA_NEXT);
+
+      mMediaSessionActionReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+          if (intent.getAction().equals(KEY_MEDIA_PAUSE)) {
+            Log.d("SERVOMEDIA", "PAUSE");
+          } else if (intent.getAction().equals(KEY_MEDIA_STOP)) {
+            Log.d("SERVOMEDIA", "STOP");
+          } else if (intent.getAction().equals(KEY_MEDIA_NEXT)) {
+            Log.d("SERVOMEDIA", "NEXT");
+          } else if (intent.getAction().equals(KEY_MEDIA_PREV)) {
+            Log.d("SERVOMEDIA", "PREV");
+          }
+        }
+      };
+
+      registerReceiver(mMediaSessionActionReceiver, filter);
+
+      Intent pauseIntent = new Intent(KEY_MEDIA_PAUSE);
+      Notification.Action pauseAction =
+        new Notification.Action(R.drawable.media_session_pause, "Pause",
+          PendingIntent.getBroadcast(context, 0, pauseIntent, 0));
+
+      Intent nextIntent = new Intent(KEY_MEDIA_NEXT);
+      Notification.Action nextAction =
+        new Notification.Action(R.drawable.media_session_next, "Next",
+          PendingIntent.getBroadcast(context, 0, nextIntent, 0));
+
+      Intent prevIntent = new Intent(KEY_MEDIA_PREV);
+      Notification.Action prevAction =
+        new Notification.Action(R.drawable.media_session_prev, "Previous",
+          PendingIntent.getBroadcast(context, 0, prevIntent, 0));
+
+      Intent stopIntent = new Intent(KEY_MEDIA_STOP);
+      Notification.Action stopAction =
+        new Notification.Action(R.drawable.media_session_stop, "Stop",
+          PendingIntent.getBroadcast(context, 0, stopIntent, 0));
+
+      Notification.Builder builder = new Notification.Builder(context, this.MEDIA_CHANNEL_ID);
+      builder
+        .setSmallIcon(R.drawable.media_session_icon)
+        .setContentTitle("This is the notification title")
+        .setVisibility(Notification.VISIBILITY_PUBLIC)
+        .addAction(prevAction)
+        .addAction(pauseAction)
+        .addAction(nextAction)
+        .addAction(stopAction)
+        .setStyle(new Notification.MediaStyle()
+            .setShowActionsInCompactView(1 /* pause button */ )
+            .setShowActionsInCompactView(3 /* stop button */));
+
+      NotificationManager notificationManager = getSystemService(NotificationManager.class);
+      notificationManager.notify(mNotificationID.getNext(), builder.build());
+    }
+
+    private void hideMediaSessionControls() {
+      Log.d("SERVOMEDIA", "hideMediaSessionControls");
+      NotificationManager notificationManager = getSystemService(NotificationManager.class);
+      notificationManager.cancel(mNotificationID.get());
+      unregisterReceiver(mMediaSessionActionReceiver);
+    }
+
+
 }

support/android/apk/servoapp/src/main/res/values/strings.xml

@@ -1,3 +1,5 @@
 <resources>
-    <string name="app_name">Servo</string>
+  <string name="app_name">Servo</string>
+  <string name="media_channel_name">ServoMedia</string>
+  <string name="media_channel_description">Notication channel for multimedia activity</string>
 </resources>