It is the basic "navigation interface" of the system. If you want to attach an interface to the navigation system, you only need it to create your interface.
Note: This interface itself has no focus. If you need to focus, you need to enable IsFocusable in its property details panel:
In addition, the interface supports nesting, but generally, nesting is not required. You can design it freely according to your needs.
It inherits from 1. UISystemWidgetBase，Therefore, it has all the overridable functions of UISystemWidgetBase.
Delegated event: OnClicked, which is used to bind in other interfaces.
This also applies to mouse, keyboard and game controller to simulate click events.
Delegated events: OnHovered and OnUnhovered, which are used to bind to other interfaces.
This also applies to mouse, keyboard and game controllers to simulate hover and unhover events.
