[gtkmm] Gtk::ApplicationWindow: Disambiguate activate_action()

[Kjell Ahlstedt <kjellahl src gnome org>]

commit aecbdbf33298853581f493ddb8b948f4a99975fa
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Tue Jul 26 18:48:38 2022 +0200

    Gtk::ApplicationWindow: Disambiguate activate_action()
    
    A call to activate_action() is a call to Gtk::Widget::activate_action(),
    not a call to Gio::ActionGroup::activate_action().
    Fixes #122

 gtk/src/applicationwindow.hg | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)
---
diff --git a/gtk/src/applicationwindow.hg b/gtk/src/applicationwindow.hg
index bc66df4b..fce17931 100644
--- a/gtk/src/applicationwindow.hg
+++ b/gtk/src/applicationwindow.hg
@@ -31,11 +31,10 @@ class GTKMM_API ShortcutsWindow;
 
 /** A Gtk::Window subclass with Gtk::Application support.
  *
- * ApplicationWindow is a Gtk::Window subclass that offers some
+ * %ApplicationWindow is a Gtk::Window subclass that offers some
  * extra functionality for better integration with Gtk::Application
  * features.  Notably, it can handle both the application menu as well
- * as the menubar. See set_app_menu() and
- * set_menubar().
+ * as the menubar. See set_app_menu() and set_menubar().
  *
  * This class derives from Gio::ActionGroup and Gio::ActionMap,
  * to let you add window-specific actions that will be exported by the
@@ -43,9 +42,10 @@ class GTKMM_API ShortcutsWindow;
  * actions.  Window-specific actions are prefixed with the "win."
  * prefix and application-wide actions are prefixed with the "app."
  * prefix.  Actions must be addressed with the prefixed name when
- * referring to them from a Gio::MenuModel.
+ * referring to them from a Gio::MenuModel, or in activate_action().
+ * Gio::ActionGroup::activate_action() does not accept prefixes.
  *
- * Note that widgets that are placed inside a Gtk::ApplicationWindow
+ * Note that widgets that are placed inside a %Gtk::ApplicationWindow
  * can also activate these actions, if they implement the
  * Gtk::Actionable interface.
  *
@@ -54,7 +54,7 @@ class GTKMM_API ShortcutsWindow;
  * be held when activating actions locally (if GDK threads are enabled).
  *
  * The settings Gtk::Settings::property_gtk_shell_shows_app_menu() and
- * Gtk::Settings::property_gtk_shell_shows_menubar() tell GTK+ whether the
+ * Gtk::Settings::property_gtk_shell_shows_menubar() tell GTK whether the
  * desktop environment is showing the application menu and menubar
  * models outside the application as part of the desktop shell.
  * For instance, on OS X, both menus will be displayed remotely;
@@ -62,11 +62,9 @@ class GTKMM_API ShortcutsWindow;
  * will display the application menu, but not the menubar.
  *
  * If the desktop environment does not display the menubar, then
- * Gtk::ApplicationWindow will automatically show a Gtk::MenuBar for it.
- * (see the <a 
href="http://developer.gnome.org/gtk3/stable/GtkApplication.html#GtkApplication.description";>GtkApplication 
documentation</a> for some screenshots of how this
- * looks on different platforms).
- * This behaviour can be overridden with the Gtk::ApplicationWindow::property_show_menubar()
- * property. If the desktop environment does not display the application
+ * %Gtk::ApplicationWindow will automatically show a menubar for it.
+ * This behaviour can be overridden with property_show_menubar().
+ * If the desktop environment does not display the application
  * menu, then it will automatically be included in the menubar.
  */
 class GTKMM_API ApplicationWindow
@@ -79,6 +77,14 @@ class GTKMM_API ApplicationWindow
   _IMPLEMENTS_INTERFACE(Gio::ActionMap)
   _UNMANAGEABLE
 public:
+  // Disambiguate calls to activate_action().
+  // g_action_group_activate_action() and gtk_widget_activate_action() are
+  // very similar, but gtk_widget_activate_action() requires a "win." prefix.
+  // If you prefer g_action_group_activate_action(), call
+  // Gio::ActionGroup::activate_action().
+  // https://discourse.gnome.org/t/which-activate-action-shall-be-chosen-in-gtkapplicationwindow/10555/2
+  using Widget::activate_action;
+
   _CTOR_DEFAULT
   explicit ApplicationWindow(const Glib::RefPtr<Application>& application);
 dnl // Don't ignore gtk_application_window_new(). h2def.py erroneously classifies