static void DragSource_PreviewMouseMove(object sender, MouseEventArgs e)
{
if (_mDragInfo == null && _mBolPreviewMouseLeftButtonDown)
{
_mBolPreviewMouseLeftButtonDown = false;
if (HitTestScrollBar(sender, e))
{
_mDragInfo = null;
return;
}
_mDragInfo = new DragInfo(sender, e);
IDragSource dragHandler = GetDragHandler(_mDragInfo.VisualSource);
if (dragHandler != null)
{
_mDragInfo.Data = dragHandler.DragData();
}
}
if (_mDragInfo != null)
{
Point dragStart = _mDragInfo.DragStartPosition;
Point position = e.GetPosition(null);
if (Math.Abs(position.X - dragStart.X) > SystemParameters.MinimumHorizontalDragDistance ||
Math.Abs(position.Y - dragStart.Y) > SystemParameters.MinimumVerticalDragDistance)
{
var dragHandler = GetDragHandler(_mDragInfo.VisualSource);
if (dragHandler != null)
{
_mDragInfo.Effects = dragHandler.StartDrag(_mDragInfo.Data);
if (_mDragInfo.Effects != DragDropEffects.None && _mDragInfo.Data != null)
{
var data = new DataObject(MFormat.Name, _mDragInfo.Data);
System.Windows.DragDrop.DoDragDrop(_mDragInfo.VisualSource, data, _mDragInfo.Effects);
_mDragInfo = null;
}
}
}
}
}