protected override void DragStart(object sender, MouseEventArgs e)
{
var source = e.OriginalSource as DependencyObject;
if (Utils.FindParentOfTypes(source, fileDragSources) is FrameworkElement parent)
{
var args = new UiFileDragArgs
{
Element = parent,
Source = parent.DataContext
};
CallOnDragChain(args);
if (args.Files?.Count > 0)
{
var dataObject = new DataObject(DataFormats.FileDrop, args.Files.ToArray());
dataObject.SetData(AdditionalKey, new object());
DragDrop.DoDragDrop(source, dataObject, DragDropEffects.Move);
foreach (var file in args.Files)
{
if (File.Exists(file))
{
File.Delete(file);
}
}
startPosition = null;
}
}
}
private void CallOnDragChain(UiFileDragArgs args)
{
OnFileDrag?.Invoke(args);
if (args.Files?.Count > 0)
{
return;
}
if (args.Element.DataContext is IFileDragDropAware parentAware)
{
parentAware.OnFileDrag(args);
if (args.Files?.Count > 0)
{
return;
}
}
if (args.Element != containerElement && containerElement.DataContext is IFileDragDropAware elementAware)
{
elementAware.OnFileDrag(args);
}
}