Add child to user created widgets, possible?

When you create a UMG widget in the editor and add e.g. a VerticalBox, it is possible to simply drag other widgets onto it (add child widgets). Is this somehow possible to achieve with User Created widgets?

Example of need:
I would like to have a widget that represents a window that has a title bar area (not talking about the widget WindowTitleBarArea). Now when creating another widget, I would like to drag in that User Created window and add stuff into the child area.

The same for a background. Create a background widget and simply drag it in from the User Created widgets and drop childs onto it.

Is it somehow possible to achieve that? Is there some naming trick like: Name that container XY and it will be the drop target?

I have serveral workarounds in mind, but they are just workarounds…

Have you tried using Named Slots? It basically opens up a spot for you to drag whatever you want into your user created widget.

Just plop a “Named Slot” widget where you want in your user created widget. When you now use your user created widget you should see an arrow next to it in the Hierarchy panel where you’ll find the Named Slot.

Awesome thanks. That’s exactly what I was looking for. Ever wondered what those ‘NamedSlots’ are for.
(Sorry for the late reply)