private void SpectrumMouseClick(object sender, MouseButtonEventArgs e)
 {
     if (e.ClickCount == 2)
     {
         //Double click to set Marker
         Point  point       = Mouse.GetPosition(e.Source as FrameworkElement);
         double xIndexScale = point.X / mWriteableBmpForSpectrumChart.Width;
         mViewModel.SetCurrentMarkerXIndex(xIndexScale);
     }
 }