MultiButton widget is a button widget with ability to change active button by end user in application. User may hold left mouse button over a widget for a little time (controlled by Delay property) to get list of all available buttons and make any one of them active by releasing mouse button over selected button.
To add button to a list use
AddButton() methods. Buttons can also be added and removed in Form Builder in Hierarchy Editor.
List of buttons can appear in any of four directions (left, top, right, bottom) and this behaviour is controlled by OpenDirection property.
When widget is focused user can also use Up, Down, Left and Right (depends on open direction) arrow buttons on keyboard to change active button.
Below you can see how MultiButton widget looks like in regular (left) and opened (right) modes.