/// <summary>
/// Drag handler. Element is being dragged.
/// </summary>
/// <param name="sender"></param>
/// <param name="args"></param>
protected void DragMove(Object sender, DragDropEventArgs args)
{
var o = args.AnchorPosition - args.HitPosition;
var p = layer.Map.PointFromScreen(args.Position);
Point = layer.ToWorld(p + o);
}
/// <summary>
/// Inserts a new via way point and attaches a Drag&Drop operation to it.
/// </summary>
/// <param name="style">Display style of the way point</param>
/// <param name="initialPosition">Initial position</param>
/// <param name="position">Current position</param>
public void BeginDragVia(ShapeStyle style, Point initialPosition, Point?position = null)
{
// the via location in world coordinates
var pointOnMap = layer.ToWorld(layer.Map.PointFromScreen(initialPosition));
// insert the via way point then attach the drag and drop operation to it.
InsertVia(pointOnMap, style).BeginDrag(initialPosition, position);
}