Windows Store App, Shaken

Accelerometer _accelerometer;
int _shakeCount = 0;
public MainPage()
{
this.InitializeComponent();
_accelerometer=Accelerometer.GetDefault();
if (_accelerometer != null)
_accelerometer.Shaken += new TypedEventHandler<Accelerometer, AccelerometerShakenEventArgs>(Shaken);
}

async private void Shaken(object sender, AccelerometerShakenEventArgs e)
{
await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
{
_shakeCount++;
});

if (_shakeCount >= 3)
{
//method call
_shakeCount = 0;
}
}