Class Choice

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Pick-one menu button

Inherits from Menu_


This is a button that when pushed pops up a menu (or hierarchy of menus) composed of menu items. Motif calls this an OptionButton.

The only difference between this and a Menu_Button is that the name of the most recent chosen menu item is displayed inside the box, while the label is displayed outside the box. However, since the use of this is most often to control a single variable rather than do individual callbacks, some of the Menu_Button methods are redescribed here in those terms.

When the user picks an item off the menu the value is set to the index of that item and then the callback is done.

All three mouse buttons pop up the menu. The Forms behavior of the first two buttons to increment/decrement the choice is not implemented. This could be added with a subclass, however.

The menu will also pop up in response to shortcuts indicated by putting a '&' character in the label. See Button for a description of this.

Typing the shortcut of any of the items will do exactly the same as when you pick the item with the mouse. The '&' character in item names are only looked at when the menu is popped up, however.

The changed property is true if the user has picked a different value. It's turned off by setting value, and just before performing a callback; the callback can turn it back on if desired.

The down_box attribute is used when the menu is popped up. It defaults to Boxtype.down.

doctool generated at Sun Aug 12 22:23:18 2001