private async void BatteryService_BatteryStateChanged(object sender, BatteryStateChangedEventArgs e)
 {
     await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () => UpdateBattery(e.Data));
 }
 private void BatteryService_BatteryStateChanged(object sender, BatteryStateChangedEventArgs e)
 {
     Dispatcher.BeginInvoke(new Action(() => UpdateBattery(e.Data)));
 }