OptionMenu

An OptionMenu appears as a button with either a pixmap or text label value next 
to a small indicator. The label value indicates the current value of the 
OptionMenu. Pressing the button causes the full set of available values to 
appear in a RowColumn menu on top of the button. The menu is displayed relative 
to the current OptionMenu label values position. The menu remains displayed
as long as the button is pressed. To choose an alternative value, slide the 
cursor along the RowColumn menu and release the button. The RowColumn menu
value selected with the cursor when the button is released now becomes the
new OptionMenus label value.

