Toc Gallery Index Tree Gtk.UI_Manager

Hierarchy

Description

A Gtk_UI_Manager constructs a user interface (menus and toolbars) from one or more UI definitions, which reference actions from one or more action groups.

------------------- UI Definitions -- -------------------

The UI definitions are specified in an XML format which can be roughly described by the following DTD. - - - - - - - - - - - - - - - - - - -

There are some additional restrictions beyond those specified in the DTD, e.g. every toolitem must have a toolbar in its ancestry and every menuitem must have a menubar or popup in its ancestry. Since a GMarkup parser is used to parse the UI description, it must not only be valid XML, but valid GMarkup.

If a name is not specified, it defaults to the action. If an action is not specified either, the element name is used. The name and action attributes must not contain '/' characters after parsing (since that would mess up path lookup) and must be usable as XML attributes when enclosed in doublequotes, thus they must not '"' characters or references to the " entity.

Here is an example:

The constructed widget hierarchy is very similar to the element tree of the XML, with the exception that placeholders are merged into their parents. The correspondence of XML elements to widgets should be almost obvious:

- menubar : a Gtk_Menu_Bar - toolbar : a Gtk_Toolbar - popup : a toplevel Gtk_Menu - menu : a Gtk_Menu attached to a menuitem - menuitem : a Gtk_Menu_Item subclass, the exact type depends on the action - toolitem : a Gtk_Tool_Item subclass, exact type depends on the action. This may contain a menu element only if the associated action specifies a Gtk_Menu_Tool_Button as proxy - separator : a Gtk_Separator_Menu_Item or Gtk_Separator_Tool_Item - accelerator : a keyboard accelerator

The "position" attribute determines where a constructed widget is positioned wrt. to its siblings in the partially constructed tree. If it is "top", the widget is prepended, otherwise it is appended.

--------------- UI Merging -- ---------------

The most remarkable feature of Gtk_UI_Manager is that it can overlay a set of menuitems and toolitems over another one, and demerge them later.

Merging is done based on the names of the XML elements. Each element is identified by a path which consists of the names of its anchestors, separated by slashes. For example, the menuitem named "Left" in the example above has the path /ui/menubar/JustifyMenu/Left and the toolitem with the same name has path /ui/toolbar1/JustifyToolItems/Left.

----------------- Accelerators -- -----------------

Every action has an accelerator path. Accelerators are installed together with menuitem proxies, but they can also be explicitly added with elements in the UI definition. This makes it possible to have accelerators for actions even if they have no visible proxies.

--------------------- Smart Separators -- ---------------------

The separators created by Gtk_UI_Manager are "smart", i.e. they do not show up in the UI unless they end up between two visible menu or tool items. Separators which are located at the very beginning or end of the menu or toolbar containing them, or multiple separators next to each other, are hidden. This is a useful feature, since the merging of UI elements from multiple sources can make it hard or impossible to determine in advance whether a separator will end up in such an unfortunate position.

For separators in toolbars, you can set expand="true" to turn them from a small, visible separator to an expanding, invisible one. Toolitems following an expanding separator are effectively right-aligned.

---------------- Empty Menus -- ----------------

Submenus pose similar problems to separators inconnection with merging. It is impossible to know in advance whether they will end up empty after merging. Gtk_UI_Manager offers two ways to treat empty submenus:

- make them disappear by hiding the menu item they're attached to - add an insensitive "Empty" item

The behaviour is chosen based on the "hide_if_empty" property of the action to which the submenu is associated.

Types

  • type Gtk_UI_Manager is access all Gtk_UI_Manager_Record'Class;
  • type Gtk_UI_Manager_Record is new Glib.Object.GObject_Record with null record;
  • type Manager_Item_Type is mod 2 ** 16;

Subprograms

    Creation

  • procedure Gtk_New (UI : out Gtk_UI_Manager);
    procedure Initialize (UI : access Gtk_UI_Manager_Record'Class);
    Creates a new ui manager object.
  • function Get_Type return GType;
    Return the internal value associated with a Gtk_UI_Manager.
  • function New_Merge_Id (Self : access Gtk_UI_Manager_Record) return Guint;
    Returns an unused merge id, suitable for use with Add_UI.
  • procedure Ensure_Update (Self : access Gtk_UI_Manager_Record);
    Makes sure that all pending updates to the UI have been completed. This may occasionally be necessary, since Gtk_UI_Manager updates the UI in an idle function. A typical example where this function is useful is to enforce that the menubar and toolbar have been added to the main window before showing it: Add (Window, Vbox); Connect (Merge, "add_widget", Add_Widget'Access, Vbox); Add_UI_From_File (Merge, "my-menus"); Add_UI_From_File (Merge, "my-toolbars"); Ensure_Update (Merge); Show (Window);
  • Merging contents

  • procedure Add_UI (Self : access Gtk_UI_Manager_Record; Merge_Id : Guint; Path : String; Name : String; Action : String := ""; Typ : Manager_Item_Type := Manager_Auto; Top : Boolean := False);
    procedure Remove_UI (Self : access Gtk_UI_Manager_Record; Merge_Id : Guint);
    Adds a UI element to the current contents of Self.

    If Typ is Manager_Auto, GTK+ inserts a menuitem, toolitem or separator if such an element can be inserted at the place determined by Path. Otherwise Typ must indicate an element that can be inserted at the place determined by Path.

    If Path points to a menuitem or toolitem, the new element will be inserted before or after this item, depending on Top.

    Merge_Id: see New_Merge_Id. Action should be the empty string for a separator.

  • function Add_UI_From_File (Self : access Gtk_UI_Manager_Record; Filename : String; Error : Glib.Error.GError_Access := null) return Guint;
    Parses a file containing a UI definition and merges it with the current contents of Self. Return value: The merge id for the merged UI. The merge id can be used to unmerge the UI with Remove_UI. If an error occurred, the return value is 0, and if Error was specified it is set to the error message.
  • function Add_UI_From_String (Self : access Gtk_UI_Manager_Record; Buffer : String; Error : Glib.Error.GError_Access := null) return Guint;
    Parses a string containing a UI definition and merges it with the current contents of Self. An enclosing element is added if it is missing. Return value: The merge id for the merged UI. The merge id can be used to unmerge the UI with Remove_UI. If an error occurred, the return value is 0, and if Error was specified it is set to the error message.
  • procedure Insert_Action_Group (Self : access Gtk_UI_Manager_Record; Action_Group : access Gtk.Action_Group.Gtk_Action_Group_Record'Class; Pos : Gint);
    procedure Remove_Action_Group (Self : access Gtk_UI_Manager_Record; Action_Group : access Gtk.Action_Group.Gtk_Action_Group_Record'Class);
    Inserts an action group into the list of action groups associated with Self. Actions in earlier groups hide actions with the same name in later groups. with Self.
  • Querying contents

  • function Get_Accel_Group (Self : access Gtk_UI_Manager_Record) return Gtk.Accel_Group.Gtk_Accel_Group;
    Returns the Gtk_Accel_Group associated with Self.
  • function Get_Action (Self : access Gtk_UI_Manager_Record; Path : String) return Gtk.Action.Gtk_Action;
    Looks up an action by following a path. See Get_Widget for more information about paths. Returns the action whose proxy widget is found by following the path, or null if no widget was found.
  • function Get_Action_Groups (Self : access Gtk_UI_Manager_Record) return Glib.Object.Object_Simple_List.Glist;
    Returns the list of action groups associated with Self. The returned list should not be modified.
  • procedure Set_Add_Tearoffs (Self : access Gtk_UI_Manager_Record; Add_Tearoffs : Boolean);
    function Get_Add_Tearoffs (Self : access Gtk_UI_Manager_Record) return Boolean;
    Sets the "add_tearoffs" property, which controls whether menus generated by this Gtk_UI_Manager will have tearoff menu items. Note that this only affects regular menus. Generated popup menus never have tearoff menu items.
  • function Get_Toplevels (Self : access Gtk_UI_Manager_Record; Types : Manager_Item_Type) return Gtk.Widget.Widget_SList.GSlist;
    Obtains a list of all toplevel widgets of the requested types. Types may contain Manager_Menubar, Manager_Toolbar or Manager_Popup. The returned list must be freed by the caller.
  • function Get_UI (Self : access Gtk_UI_Manager_Record) return String;
    Create a UI definition of the merged UI
  • function Get_Widget (Self : access Gtk_UI_Manager_Record; Path : String) return Gtk.Widget.Gtk_Widget;
    Looks up a widget by following a path. The path consists of the names specified in the XML description of the UI. separated by '/'. Elements which don't have a name or action attribute in the XML (e.g. <popup>) can be addressed by their XML element name (e.g. "popup"). The root element ("/ui") can be omitted in the path.

    Note that the widget found by following a path that ends in a

    ; element is the menuitem to which the menu is attached, not the menu itself.

    Also note that the widgets constructed by a ui manager are not tied to the lifecycle of the ui manager. If you add the widgets returned by this function to some container or explicitly ref them, they will survive the destruction of the ui manager.

Signals

  • actions_changed
    procedure Handler (UI : access Gtk_UI_Manager_Record'Class);
    This signal is emitted whenever the set of actions changes.
  • add_widget
    procedure Handler (UI : access Gtk_UI_Manager_Record'Class; Widget : access Gtk_Widget_Record'Class);
    The add_widget signal is emitted for each generated menubar and toolbar. It is not emitted for generated popup menus, which can be obtained by Get_Widget.
  • connect_proxy
    procedure Handler (UI : access Gtk_UI_Manager_Record'Class; Action : access Gtk_Action_Record'Class; Proxy : access Gtk_Widget_Record'Class);
    This signal is emitted after connecting a proxy to an action in the group. This is intended for simple customizations for which a custom action class would be too clumsy, e.g. showing tooltips for menuitems in the statusbar.
  • disconnect_proxy
    procedure Handler (UI : access Gtk_UI_Manager_Record'Class; Action : access Gtk_Action_Record'Class; Proxy : access Gtk_Widget_Record'Class);
    The disconnect_proxy signal is emitted after disconnecting a proxy from an action in the group.
  • post_activate
    procedure Handler (UI : access Gtk_UI_Manager_Record'Class; Action : access Gtk_Action_Record'Class);
    The post_activate signal is emitted just after the action is activated. This is intended for applications to get notification just after any action is activated.
  • pre_activate
    procedure Handler (UI : access Gtk_UI_Manager_Record'Class; Action : access Gtk_Action_Record'Class);
    The pre_activate signal is emitted just before the action is activated. This is intended for applications to get notification just before any action is activated.

Properties

  • Add_Tearoffs_Property
    Boolean
    Whether tearoff menu items should be added to menus
  • Ui_Property
    String
    An XML string describing the merged UI

Alphabetical Index