Superclass for UI elements. Doesn't have functionality by itself, use child subclasses instead.
Return the game object that this UI element is attached to. Returns undefined if the element isn't attached to a game object.
Return the widget that contains this widget, for example a border that wraps a check box. Returns undefined if this object has no parent.
Return whether the widget is currently enabled (see setEnabled).
Set whether the widget is enabled. When a widget is disabled, users can't interact with it and it is greyed out. When a widget that contains other widgets (like VerticalBox) is disabled, all its children behave as if disabled, too. By default, widgets are enabled.
Whether to enable the widget.