Frame layout is used to display a single view at a time. The view can contain many widgets but only one will appear at a time.

See this example the view has two image views but only one of them is displayed at a time which is the last view defined in the file. The frame layout displays views as if they are in a stack.

If we have two image views one displays a blue box and the other displays a red box, the blue is bigger than the red one, it would be like this: