Merge pull request #11 in THFM/fm.touhou.touhoufm from...

Merge pull request #11 in THFM/fm.touhou.touhoufm from bugfix/THFMA-5-nullpointer-exception-in-radioservice to development

* commit 'b21e3956':
  Fix NullPointer exception in RadioService

app/src/main/java/fm/touhou/touhoufm/service/RadioService.java

@@ -293,7 +293,8 @@ public class RadioService extends Service implements AudioManager.OnAudioFocusCh
         runOnUiThread(new Runnable() {
             @Override
             public void run() {
-                activity.setPlayingStatus(false);
+                if(activity != null)
+                    activity.setPlayingStatus(false);
                 mBuilder.setContentText("Stopped").setSmallIcon(R.drawable.ic_stat_stopped);
                 mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
             }