private void OnDragOver(object sender, Telerik.Windows.DragDrop.DragEventArgs e)
{
object sourceItem = DragDropPayloadManager.GetDataFromObject(e.Data, __dragSource);
TreeListViewRow destinationRow = (e.OriginalSource as TreeListViewRow) ?? (e.OriginalSource as FrameworkElement).ParentOfType <TreeListViewRow>();
GridViewScrollViewer destinationTree = (e.OriginalSource as GridViewScrollViewer) ?? (e.OriginalSource as FrameworkElement).ParentOfType <GridViewScrollViewer>();
if (destinationRow != null && destinationRow.Item != sourceItem)
{
e.Effects = !IsChildOf(destinationRow, sourceItem) ? DragDropEffects.Move : DragDropEffects.None;
if (e.Effects == DragDropEffects.Move)
{
DragDropPayloadManager.SetData(e.Data, __dragTarget, destinationRow.Item);
}
}
else if (destinationTree != null)
{
DragDropPayloadManager.SetData(e.Data, __dragTarget, string.Empty);
}
else
{
e.Effects = DragDropEffects.None;
}
e.Handled = true;
}
void AssociatedObject_DataLoaded(object sender, EventArgs e)
{
this.AssociatedObject.DataLoaded -= new EventHandler <EventArgs>(AssociatedObject_DataLoaded);
this.AttachDropPositionFeedback();
this.scrollViewer = this.AssociatedObject.ChildrenOfType <GridViewScrollViewer>().FirstOrDefault();
this.scrollViewer.ScrollChanged += new ScrollChangedEventHandler(scrollViewer_ScrollChanged);
this.scrollViewerScrollTimer = new DispatcherTimer()
{
Interval = TimeSpan.FromSeconds(0.02)
};
this.scrollViewerScrollTimer.Tick += new EventHandler(this.OnScrollViewerScrollTimerCompleted);
}