A Menu is a type of control that integrates a series of options, also called items or MenuItems. Each of them consists of a short text, optionally an icon and optionally also a keyboard shortcut, such as the classic Ctrl+C/Ctrl+V for copy and paste. Additionally, an item can host a submenu, forming a hierarchy with different levels of depth. In Products you have an example application that uses menus.

Use menu_create to create a menu.
Use menu_destroy to destroy a menu.
Use menu_item to add an option.
Use menu_launch to launch a popup menu.
Use osapp_menubar to set the application menu bar.

We must explicitly destroy any menu that we create in the application, just as happens with windows.

By destroying a menu, all its elements are implicitly destroyed.

Generally, we have two ways to launch or show menu. On the one hand, the menu bars (Figure 1), which are anchored to a window, although there are operating systems (such as macOS) that display the menu bar at the top of the screen. On the other hand, the popup or contextual menus (Figure 2) that are displayed at any time during execution as an overlaid window, normally when you right-click on some element of the interface.

Screenshot of the menu bar of a desktop application. — Figure 1: Menu bar in Windows, macOS and Linux.

The concept of the menu, like that of the window, exists from the origin of the graphic interfaces. The first computer to incorporate them was the Xerox Alto that appeared in 1973 and its commercial successor the Xerox Star. Concepts still very alive today such as: Menu, Window, Icon, Desk, or Mouse were already present on these computers that served as inspiration to Steve Jobs in the creation of Apple Lisa (Figure 3), predecessor of Machintosh and inspirer of Microsoft Windows.

Apple Lisa desktop environment capture. — Figure 3: The Apple Lisa was one of the first systems to incorporate menus as part of the graphical interface.

menu_create ()

Create a new menu.

Menu*
menu_create(void);

Return

The new menu.

menu_destroy ()

Destroy a menu and its entire hierarchy.

void
menu_destroy(Menu **menu);

menu	The menu. Will be set to `NULL` after destruction.

menu_launch ()

Launch a menu as secondary or PopUp.

void
menu_launch(Menu *menu,
            const V2Df position);

menu	The menu.
position	Coordinates of the upper left corner.

menu_hide ()

Hides a secondary PopUp menu.

void
menu_hide(Menu *menu);

The menu.

menu_item ()

Add an item to the menu.

void
menu_item(Menu *menu,
          MenuItem *item);

menu	The menu.
item	The item to add.

menu_off_items ()

Set status ekGUI_OFF for all menu items.

void
menu_off_items(Menu *menu);

The menu.

menu_get_item ()

Get an item from the menu.

MenuItem*
menu_get_item(Menu *menu,
              const uint32_t index);

menu	The menu.
index	The index of the item.

Return

The item.

menu_size ()

Gets the number of items.

uint32_t
menu_size(const Menu *menu);

The menu.

Return

Number of items.

Menu*	menu_create (void)
void	menu_destroy (...)
void	menu_launch (...)
void	menu_hide (...)
void	menu_item (...)
void	menu_off_items (...)
MenuItem*	menu_get_item (...)
uint32_t	menu_size (...)

Menu

Functions

menu_create ()

menu_destroy ()

menu_launch ()

menu_hide ()

menu_item ()

menu_off_items ()

menu_get_item ()

menu_size ()