Interfacing Raku to Gnome GTK+

Gnome::Gtk3::MenuShell

A base class for menu objects

Description

A Gnome::Gtk3::MenuShell is the abstract base class used to derive the Gnome::Gtk3::Menu and Gnome::Gtk3::MenuBar subclasses.

A Gnome::Gtk3::MenuShell is a container of Gnome::Gtk3::MenuItem objects arranged in a list which can be navigated, selected, and activated by the user to perform application functions. A Gnome::Gtk3::MenuItem can have a submenu associated with it, allowing for nested hierarchical menus.

Terminology

A menu item can be “selected”, this means that it is displayed in the prelight state, and if it has a submenu, that submenu will be popped up.

A menu is “active” when it is visible onscreen and the user is selecting from it. A menubar is not active until the user clicks on one of its menuitems. When a menu is active, passing the mouse over a submenu will pop it up.

There is also is a concept of the current menu and a current menu item. The current menu item is the selected menu item that is furthest down in the hierarchy. (Every active menu shell does not necessarily contain a selected menu item, but if it does, then the parent menu shell must also contain a selected menu item.) The current menu is the menu that contains the current menu item. It will always have a GTK grab and receive all key presses.

Synopsis

Declaration

unit class Gnome::Gtk3::MenuShell;
also is Gnome::Gtk3::Container;

Methods

new

Create an object using a native object from elsewhere. See also Gnome::GObject::Object.

multi method new ( N-GObject :$native-object! )

Create an object using a native object from a builder. See also Gnome::GObject::Object.

multi method new ( Str :$build-id! )

[gtk_] menu_shell_append

Adds a new Gnome::Gtk3::MenuItem to the end of the menu shell’s item list.

method gtk_menu_shell_append ( N-GObject $child )
  • N-GObject $child; (type Gnome::Gtk3::.MenuItem): The Gnome::Gtk3::MenuItem to add

[gtk_] menu_shell_prepend

Adds a new Gnome::Gtk3::MenuItem to the beginning of the menu shell’s item list.

method gtk_menu_shell_prepend ( N-GObject $child )
  • N-GObject $child; The Gnome::Gtk3::MenuItem to add

[gtk_] menu_shell_insert

Adds a new Gnome::Gtk3::MenuItem to the menu shell’s item list at the position indicated by position.

method gtk_menu_shell_insert ( N-GObject $child, Int $position )

  • N-GObject $child; The Gnome::Gtk3::MenuItem to add

  • Int $position; The position in the item list where child is added. Positions are numbered from 0 to n-1

[gtk_] menu_shell_deactivate

Deactivates the menu shell.

Typically this results in the menu shell being erased from the screen.

method gtk_menu_shell_deactivate ( )

[[gtk_] menu_shell_] select_item

Selects the menu item from the menu shell.

method gtk_menu_shell_select_item ( N-GObject $menu_item )
  • N-GObject $menu_item; The Gnome::Gtk3::MenuItem to select

[gtk_] menu_shell_deselect

Deselects the currently selected item from the menu shell, if any.

method gtk_menu_shell_deselect ( )

[[gtk_] menu_shell_] activate_item

Activates the menu item within the menu shell.

method gtk_menu_shell_activate_item ( N-GObject $menu_item, Int $force_deactivate )

  • N-GObject $menu_item; the Gnome::Gtk3::MenuItem to activate

  • Int $force_deactivate; if 1, force the deactivation of the menu shell after the menu item is activated

[[gtk_] menu_shell_] select_first

Select the first visible or selectable child of the menu shell; don’t select tearoff items unless the only item is a tearoff item.

Since: 2.2

method gtk_menu_shell_select_first ( Int $search_sensitive )
  • Int $search_sensitive; if 1, search for the first selectable menu item, otherwise select nothing if the first item isn’t sensitive. This should be 0 if the menu is being popped up initially.

[gtk_] menu_shell_cancel

Cancels the selection within the menu shell.

Since: 2.4

method gtk_menu_shell_cancel ( )

[[gtk_] menu_shell_] get_take_focus

Returns 1 if the menu shell will take the keyboard focus on popup.

Returns: 1 if the menu shell will take the keyboard focus on popup.

Since: 2.8

method gtk_menu_shell_get_take_focus ( --> Int  )

[[gtk_] menu_shell_] set_take_focus

If take_focus is 1 (the default) the menu shell will take the keyboard focus so that it will receive all keyboard events which is needed to enable keyboard navigation in menus.

Setting take_focus to 0 is useful only for special applications like virtual keyboard implementations which should not take keyboard focus.

The take_focus state of a menu or menu bar is automatically propagated to submenus whenever a submenu is popped up, so you don’t have to worry about recursively setting it for your entire menu hierarchy. Only when programmatically picking a submenu and popping it up manually, the take_focus property of the submenu needs to be set explicitly.

Note that setting it to 0 has side-effects:

If the focus is in some other app, it keeps the focus and keynav in the menu doesn’t work. Consequently, keynav on the menu will only work if the focus is on some toplevel owned by the onscreen keyboard.

To avoid confusing the user, menus with take_focus set to 0 should not display mnemonics or accelerators, since it cannot be guaranteed that they will work.

See also gdk_keyboard_grab()

Since: 2.8

method gtk_menu_shell_set_take_focus ( Int $take_focus )
  • Int $take_focus; 1 if the menu shell should take the keyboard focus on popup

[[gtk_] menu_shell_] get_selected_item

Gets the currently selected item.

Returns: (transfer none): the currently selected item

Since: 3.0

method gtk_menu_shell_get_selected_item ( --> N-GObject  )

[[gtk_] menu_shell_] get_parent_shell

Gets the parent menu shell.

The parent menu shell of a submenu is the Gnome::Gtk3::Menu or Gnome::Gtk3::MenuBar from which it was opened up.

Returns: (transfer none): the parent Gnome::Gtk3::MenuShell

Since: 3.0

method gtk_menu_shell_get_parent_shell ( --> N-GObject  )

[[gtk_] menu_shell_] bind_model

Establishes a binding between a Gnome::Gtk3::MenuShell and a GMenuModel.

The contents of shell are removed and then refilled with menu items according to model. When model changes, shell is updated. Calling this function twice on shell with different model will cause the first binding to be replaced with a binding to the new model. If model is Any then any previous binding is undone and all children are removed.

with_separators determines if toplevel items (eg: sections) have separators inserted between them. This is typically desired for menus but doesn’t make sense for menubars.

If action_namespace is non-Any then the effect is as if all actions mentioned in the model have their names prefixed with the namespace, plus a dot. For example, if the action “quit” is mentioned and action_namespace is “app” then the effective action name is “app.quit”.

This function uses Gnome::Gtk3::Actionable to define the action name and target values on the created menu items. If you want to use an action group other than “app” and “win”, or if you want to use a Gnome::Gtk3::MenuShell outside of a Gnome::Gtk3::ApplicationWindow, then you will need to attach your own action group to the widget hierarchy using gtk_widget_insert_action_group(). As an example, if you created a group with a “quit” action and inserted it with the name “mygroup” then you would use the action name “mygroup.quit” in your GMenuModel.

For most cases you are probably better off using gtk_menu_new_from_model() or gtk_menu_bar_new_from_model() or just directly passing the GMenuModel to gtk_application_set_app_menu() or gtk_application_set_menubar().

Since: 3.6

method gtk_menu_shell_bind_model ( N-GObject $model, Str $action_namespace, Int $with_separators )

  • N-GObject $model; (allow-none): the GMenuModel to bind to or Any to remove binding

  • Str $action_namespace; (allow-none): the namespace for actions in model

  • Int $with_separators; 1 if toplevel items in shell should have separators between them

Signals

There are two ways to connect to a signal. The first option you have is to use register-signal() from Gnome::GObject::Object. The second option is to use g_signal_connect_object() directly from Gnome::GObject::Signal.

First method

The positional arguments of the signal handler are all obligatory as well as their types. The named attributes :$widget and user data are optional.

# handler method
method mouse-event ( N-GdkEvent $event, :$widget ) { ... }

# connect a signal on window object
my Gnome::Gtk3::Window $w .= new( ... );
$w.register-signal( self, 'mouse-event', 'button-press-event');

Second method

my Gnome::Gtk3::Window $w .= new( ... );
my Callable $handler = sub (
  N-GObject $native, N-GdkEvent $event, OpaquePointer $data
) {
  ...
}

$w.connect-object( 'button-press-event', $handler);

Also here, the types of positional arguments in the signal handler are important. This is because both methods register-signal() and g_signal_connect_object() are using the signatures of the handler routines to setup the native call interface.

Supported signals

deactivate

This signal is emitted when a menu shell is deactivated.

method handler (
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menushell),
  *%user-options
);
  • $menushell; the object which received the signal

selection-done

This signal is emitted when a selection has been completed within a menu shell.

method handler (
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menushell),
  *%user-options
);
  • $menushell; the object which received the signal

move-current

An keybinding signal which moves the current menu item in the direction specified by direction.

method handler (
  Unknown type GTK_TYPE_MENU_DIRECTION_TYPE $direction,
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menushell),
  *%user-options
);

  • $menushell; the object which received the signal

  • $direction; the direction to move

activate-current

An action signal that activates the current menu item within the menu shell.

method handler (
  Int $force_hide,
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menushell),
  *%user-options
);

  • $menushell; the object which received the signal

  • $force_hide; if 1, hide the menu after activating the menu item

cancel

An action signal which cancels the selection within the menu shell. Causes the selection-done signal to be emitted.

method handler (
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menushell),
  *%user-options
);
  • $menushell; the object which received the signal

cycle-focus

A keybinding signal which moves the focus in the given direction.

method handler (
  Unknown type GTK_TYPE_DIRECTION_TYPE $direction,
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menushell),
  *%user-options
);

  • $menushell; the object which received the signal

  • $direction; the direction to cycle in

move-selected

The move-selected signal is emitted to move the selection to another item.

Returns: 1 to stop the signal emission, 0 to continue

Since: 2.12

method handler (
  Int $distance,
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menu_shell),
  *%user-options
  --> Int
);

  • $menu_shell; the object on which the signal is emitted

  • $distance; +1 to move to the next item, -1 to move to the previous

insert

The insert signal is emitted when a new Gnome::Gtk3::MenuItem is added to a Gnome::Gtk3::MenuShell. A separate signal is used instead of Gnome::Gtk3::Container::add because of the need for an additional position parameter.

The inverse of this signal is the Gnome::Gtk3::Container::removed signal.

Since: 3.2

method handler (
  N-GObject $child,
  Int $position,
  Int :$_handler_id,
  Gnome::GObject::Object :_widget($menu_shell),
  *%user-options
);

  • $menu_shell; the object on which the signal is emitted

  • $child; the Gnome::Gtk3::MenuItem that is being inserted

  • $position; the position at which the insert occurs

Properties

An example of using a string type property of a Gnome::Gtk3::Label object. This is just showing how to set/read a property, not that it is the best way to do it. This is because a) The class initialization often provides some options to set some of the properties and b) the classes provide many methods to modify just those properties. In the case below one can use new(:label(‘my text label’)) or gtk_label_set_text(‘my text label’).

my Gnome::Gtk3::Label $label .= new;
my Gnome::GObject::Value $gv .= new(:init(G_TYPE_STRING));
$label.g-object-get-property( 'label', $gv);
$gv.g-value-set-string('my text label');

Supported properties

Take Focus

A boolean that determines whether the menu and its submenus grab the keyboard focus. See gtk_menu_shell_set_take_focus() and gtk_menu_shell_get_take_focus(). Since: 2.8

The Gnome::GObject::Value type of property take-focus is G_TYPE_BOOLEAN.