protected override void DragStart(object sender, MouseEventArgs e)
{
var source = (DependencyObject)e.OriginalSource;
var sourceTypes = dragDropPairs?.Select(s => s.SourceType).ToList();
if (Utils.FindParentOfTypes(source, sourceTypes) is FrameworkElement sourceParent)
{
var args = new UiDragDropArgs
{
SourceElement = sourceParent,
Source = sourceParent.DataContext
};
CallOnDragChain(args);
DragDrop.DoDragDrop(source, new DataObject(Key, args), DragDropEffects.Link);
startPosition = null;
}
}
private void CallOnDropChain(UiDragDropArgs args)
{
args.Handled = false;
OnDrop?.Invoke(args);
if (args.Handled)
{
return;
}
if (args.Target is IDragDropAware targetAware)
{
targetAware.OnDrop(args);
if (args.Handled)
{
return;
}
}
if (args.TargetElement != containerElement && containerElement.DataContext is IDragDropAware elementAware)
{
elementAware.OnDrop(args);
}
}
private void CallOnDragChain(UiDragDropArgs args)
{
args.Handled = false;
OnDrag?.Invoke(args);
if (args.Handled)
{
return;
}
if (args.Source is IDragDropAware sourceAware)
{
sourceAware.OnDrag(args);
if (args.Handled)
{
return;
}
}
if (args.SourceElement != containerElement && containerElement.DataContext is IDragDropAware elementAware)
{
elementAware.OnDrag(args);
}
}