@Override public void onAttachedToWindow() { super.onAttachedToWindow(); IntentFilter filter = new IntentFilter(); filter.addAction(Intent.ACTION_BATTERY_CHANGED); filter.addAction(ACTION_LEVEL_TEST); final Intent sticky = getContext().registerReceiver(mTracker, filter); if (sticky != null) { // preload the battery level mTracker.onReceive(getContext(), sticky); } mAttached = true; }