void CleanUpAdorners()
{
if (_InsertAdorner != null)
{
_InsertAdorner.Dispose();
_InsertAdorner = null;
}
}
void DragEnd()
{
_AutoScroller.IsEnabled = false;
// Remove the drag adorner from the adorner layer.
CleanUpAdorners();
if (_InsertAdorner != null)
{
_InsertAdorner.Dispose();
_InsertAdorner = null;
}
if (_ItemMouseIsOver != null)
{
_ItemMouseIsOver.IsCurrentDropTarget = false;
_ItemMouseIsOver = null;
}
}
void OnDragOver(object sender, DragEventArgs e)
{
e.Effects = DragDropEffects.None;
e.Handled = true;
// drag over is the only event which returns the position
Point point = e.GetPosition(TreeView);
if (TryScroll(point))
{
return;
}
if (IsMouseOverAdorner(point))
{
return;
}
var itemsPresenter = TreeView.ScrollViewer.Content as ItemsPresenter;
/*
* if (itemsPresenter.InputHitTest(e.GetPosition(itemsPresenter)) == null)
* {
* if (insertAdorner != null) insertAdorner.Dispose();
* return;
* }
*/
if (_ItemMouseIsOver != null)
{
_ItemMouseIsOver.IsCurrentDropTarget = false;
}
_ItemMouseIsOver = GetTreeViewItemUnderMouse(point);
//if (itemMouseIsOver == null) return;
CanInsertReturn canInsertReturn = CanInsert(_ItemMouseIsOver, e.GetPosition, e.Data);
if (canInsertReturn != null)
{
e.Effects = DragDropEffects.Move;
if (_InsertAdorner == null)
{
_InsertAdorner = new InsertAdorner(_ItemMouseIsOver, new InsertContent {
Before = canInsertReturn.Before
});
}
else
{
_InsertAdorner.Dispose();
_InsertAdorner = new InsertAdorner(_ItemMouseIsOver, new InsertContent {
Before = canInsertReturn.Before
});
}
_ItemMouseIsOver.IsCurrentDropTarget = false;
}
else
{
if (_InsertAdorner != null)
{
_InsertAdorner.Dispose();
_InsertAdorner = null;
}
if (CanDrop(_ItemMouseIsOver, e.Data))
{
e.Effects = DragDropEffects.Move;
if (_ItemMouseIsOver != null)
{
_ItemMouseIsOver.IsCurrentDropTarget = true;
}
}
}
}