protected override void DropStart(object sender, DragEventArgs e)
{
var target = e.OriginalSource as DependencyObject;
var files = e.Data.GetData(DataFormats.FileDrop) as string[];
var fromHelper = e.Data.GetData(AdditionalKey) != null;
if (files?.Length > 0 && !fromHelper && Utils.FindParentOfTypes(target, fileDropTargets) is FrameworkElement parent)
{
var args = new UiFileDropArgs
{
Files = files.ToList(),
Element = parent,
Target = parent.DataContext
};
CallOnDropChain(args);
}
}
private void CallOnDropChain(UiFileDropArgs args)
{
args.Handled = false;
OnFileDrop?.Invoke(args);
if (args.Handled)
{
return;
}
if (args.Element.DataContext is IFileDragDropAware parentAware)
{
parentAware.OnFilesDrop(args);
if (args.Handled)
{
return;
}
}
if (args.Element != containerElement && containerElement.DataContext is IFileDragDropAware elementAware)
{
elementAware.OnFilesDrop(args);
}
}