3.2 Menu facilities

The menu facilities are centred around the concept of menubars. In guienv, there may be any number of menubars: an application menubar, and a menubar associated with each window. In both cases, these menubars are specified as instances of the menubar pattern:

menubar implements the facilities for defining menubars.

• append, delete and clear are used for manipulating the menus in the menubar.
• appendMenubar, replaceMenubar, and deleteMenubar is used for manipulating a menubar as part of another menubar (e.g. appending all menus in one menubar to another menubar).
• scan facilitates scanning all menus associated with this menubar.

The application menu can be specified by further binding the menubarType virtual. If a standard application menubar is what you want, just further bind to standardMenuBar.

StandardMenubar defines the following important attributes:

• standardFileMenu and standardEditMenu defines the standard file and edit menus. fileMenu, theFileMenu and editMenu, theEditMenu are facilities for specifying different file and edit menus.

The application menubar can be changed and accessed through the applicationMenubar attribute.

The individual menus in a menubar is specified as instances of the pattern menu. menu defines the following important attributes:

• name defines the name of this menu.
• onSelect is invoked when selecting in the menu. Further bind this attribute (defined in the local eventhandler virtual) to specify the actions to be executed when this manu is selected in the menubar.
• menuItem and dynamicMenuItem are used to define the individual menu items, and action is used to specify actions to be associated with dynamic menuItems (see later).
• append, delete, clear and scan are used for manipulating the menu items of this menu.
• popUp is used to pop-up this menu.
• enable and disable is used to control whether the menu is enabled or disabled in the menubar.

The pattern menuItem is the facility for defining the individual items in a menu. Most attributes (name, key, checked, etc.) define the visual appearance of the menu item. Besides the following important attributes are defined:

• onStatus is used to define when the menu item is selectable.
• onSelect is used to specify the actions to be executed when the menu item is selected.
• subMenu is used to attach an entire menu to a menu item (i.e. creating a hierarchical menu).

The separator pattern is a special menuItem that inserts a vertical line in the menu to separate groups of items.

The menuItem pattern assumes that the same actions always must be executed when a menu item is selected. If however, we want a more dynamic behaviour, the pattern dynamicMenuItem must be used. This pattern allows actions to be associated dynamically with the particular menu item. dynamicMenuItem idefines the following important attributes:

• attach and detach is used to associate the actions with this dynamicMenuItem.

The actions to be associated with a dynamicMenuItem must be instances of the menuAction pattern.