Invisible Beans
You can add an Invisible bean to your hierarchy by deselecting
everything in the hierarchy, and clicking on an invisible bean in the
palette. This results in the invisible bean appearing in your hierarchy
as a new root bean.
You can treat an invisible bean exactly as would
treat any other component in the hierarchy.
You can edit their properties with the Property Editor, access customizers (if
they have any), you can bind events to them in the Event Bindings editor, and you can cut,
copy, paste, and delete them.
Examples of invisible beans are: CheckboxGroup,
ResourceBundle, and if you have the Swing components loaded, ButtonGroup.