private void Button_Click_1(object sender, RoutedEventArgs e)
{
DrawLine line = new DrawLine(this.MyMap);
MyMap.Action = line;
// line.Fill = new SolidColorBrush(Colors.Yellow);
line.StrokeThickness = 12;
line.DrawCompleted += new EventHandler<DrawEventArgs>(Line_DrawLineCompleted);
line.Opacity = 0.3;
}