# Menus

The Athena widget set provides support for single paned non-hierarchical popup and pulldown menus. Since menus are such a common user interface tool, support for them must be provided in even the most basic widget sets. In menuing as in other areas, the Athena Widget Set provides only basic functionality.

Menus in the Athena widget set are implemented as a menu container (the SimpleMenu widget) and a collection of objects that comprise the menu entries. The SimpleMenu widget is itself a direct subclass of the OverrideShell widget class, so no other shell is necessary when creating a menu. The managed children of a SimpleMenu must be subclasses of the Sme (Simple Menu Entry) object.

The Athena widget set provides three classes of Sme objects that may be used to build menus.

Sme

  The base class of all menu entries. It may be used as a menu entry itself to provide blank space in a menu. "Sme" means "Simple Menu Entry."

SmeBSB

  This menu entry provides a selectable entry containing a text string. A bitmap may also be placed in the left and right margins. "BSB" means "Bitmap String Bitmap."

SmeLine

  This menu entry provides an unselectable entry containing a separator line.

The SimpleMenu widget informs the window manager that it should ignore its window by setting the `Override Redirect` flag. This is the correct behavior for the press-drag-release style of menu operation. If click-move-click or "pinable" menus are desired it is the responsibility of the application programmer, using the SimpleMenu resources, to inform the window manager of the menu.

To allow easy creation of pulldown menus, a MenuButton widget is also provided as part of the Athena widget set.

## Using the Menus

The default configuration for the menus is press-drag-release. The menus will typically be activated by clicking a pointer button while the pointer is over a MenuButton, causing the menu to appear in a fixed location relative to that button; this is a `pulldown` menu. Menus may also be activated
when a specific pointer and/or key sequence is used anywhere in the application; this is a `popup` menu (e.g. clicking Ctrl-<pointer
button 1> in the common application `xterm`). In this case the menu should be positioned under the cursor. Typically menus will be placed so the pointer cursor is on the first menu entry, or the last entry selected by the user.

The menu remains on the screen as long as the pointer button is held down. Moving the pointer will highlight different menu items. If the pointer leaves the menu, or moves over an entry that cannot be selected then no menu entry will highlighted. When the desired menu entry has been highlighted, releasing the pointer button removes the menu, and causes any mechanism associated with this entry to be invoked.