Add gtk_application_prefers_app_menu()

Applications can call this to determine if they should an app menu.
This will be %FALSE on desktop environments that do not have an
application menu like the one in gnome-shell.  It is %FALSE on Windows
and Mac OS.

Applications are completely free to totally ignore this API -- it is
only provided as a hint to help applications that may be interested in
supporting non-GNOME platforms with a more native 'look and feel'.

https://bugzilla.gnome.org/show_bug.cgi?id=722092

1 files changed, 34 insertions, 0 deletions

diff --git a/gtk/gtkapplication-dbus.c b/gtk/gtkapplication-dbus.c
index 09afcfa015..60d4edddf0 100644
--- a/gtk/gtkapplication-dbus.c
+++ b/gtk/gtkapplication-dbus.c
@@ -23,6 +23,7 @@
 #include "config.h"
 
 #include "gtkapplicationprivate.h"
+#include "gtksettings.h"
 
 G_DEFINE_TYPE (GtkApplicationImplDBus, gtk_application_impl_dbus, GTK_TYPE_APPLICATION_IMPL)
 
@@ -411,6 +412,38 @@ gtk_application_impl_dbus_is_inhibited (GtkApplicationImpl         *impl,
   return inhibited;
 }
 
+static gboolean
+gtk_application_impl_dbus_prefers_app_menu (GtkApplicationImpl *impl)
+{
+  static gboolean decided;
+  static gboolean result;
+
+  /* We do not support notifying if/when the result changes, so make
+   * sure that once we give an answer, we will always give the same one.
+   */
+  if (!decided)
+    {
+      GtkSettings *gtk_settings;
+      gboolean show_app_menu;
+      gboolean show_menubar;
+
+      gtk_settings = gtk_settings_get_default ();
+      g_object_get (G_OBJECT (gtk_settings),
+                    "gtk-shell-shows-app-menu", &show_app_menu,
+                    "gtk-shell-shows-menubar", &show_menubar,
+                    NULL);
+
+      /* We prefer traditional menus when we have a shell that doesn't
+       * show the appmenu or we have a shell that shows menubars
+       * (ie: Unity)
+       */
+      result = show_app_menu && !show_menubar;
+      decided = TRUE;
+    }
+
+  return result;
+}
+
 static void
 gtk_application_impl_dbus_init (GtkApplicationImplDBus *dbus)
 {
@@ -446,6 +479,7 @@ gtk_application_impl_dbus_class_init (GtkApplicationImplDBusClass *class)
   impl_class->inhibit = gtk_application_impl_dbus_inhibit;
   impl_class->uninhibit = gtk_application_impl_dbus_uninhibit;
   impl_class->is_inhibited = gtk_application_impl_dbus_is_inhibited;
+  impl_class->prefers_app_menu = gtk_application_impl_dbus_prefers_app_menu;
 
   gobject_class->finalize = gtk_application_impl_dbus_finalize;
 }