Merge branch 'issue-1863' into 'master'

Allow setting the GtkLayoutManager type per-class

Closes #1863

See merge request GNOME/gtk!821

gtk/gtkbox.c

@@ -161,6 +161,7 @@ gtk_box_class_init (GtkBoxClass *class)
 
   g_object_class_install_properties (object_class, LAST_PROP, props);
 
+  gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_BOX_LAYOUT);
   gtk_widget_class_set_accessible_role (widget_class, ATK_ROLE_FILLER);
   gtk_widget_class_set_css_name (widget_class, I_("box"));
 }
@@ -344,12 +345,9 @@ static void
 gtk_box_init (GtkBox *box)
 {
   GtkBoxPrivate *priv = gtk_box_get_instance_private (box);
-  GtkLayoutManager *box_layout = gtk_box_layout_new (GTK_ORIENTATION_HORIZONTAL);
 
   gtk_widget_set_has_surface (GTK_WIDGET (box), FALSE);
 
-  gtk_widget_set_layout_manager (GTK_WIDGET (box), box_layout);
-
   priv->orientation = GTK_ORIENTATION_HORIZONTAL;
   _gtk_orientable_set_style_classes (GTK_ORIENTABLE (box));
 }

gtk/gtkfilechooserbutton.c

@@ -422,6 +422,8 @@ gtk_file_chooser_button_class_init (GtkFileChooserButtonClass * class)
   _gtk_file_chooser_install_properties (gobject_class);
 
   gtk_widget_class_set_css_name (widget_class, I_("filechooserbutton"));
+
+  gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_BIN_LAYOUT);
 }
 
 static void
@@ -497,8 +499,6 @@ gtk_file_chooser_button_init (GtkFileChooserButton *button)
 		     target_list,
 		     GDK_ACTION_COPY);
   gdk_content_formats_unref (target_list);
-
-  gtk_widget_set_layout_manager (GTK_WIDGET (button), gtk_bin_layout_new ());
 }
 
 

gtk/gtkfilechooserwidget.c

@@ -8326,6 +8326,8 @@ gtk_file_chooser_widget_class_init (GtkFileChooserWidgetClass *class)
   gtk_widget_class_bind_template_callback (widget_class, widget_key_press_cb);
 
   gtk_widget_class_set_css_name (widget_class, I_("filechooser"));
+
+  gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_BIN_LAYOUT);
 }
 
 static void
@@ -8467,8 +8469,6 @@ gtk_file_chooser_widget_init (GtkFileChooserWidget *impl)
    */
   post_process_ui (impl);
 
-  gtk_widget_set_layout_manager (GTK_WIDGET (impl), gtk_bin_layout_new ());
-
   profile_end ("end", NULL);
 }
 

gtk/gtkfixed.c

@@ -96,11 +96,14 @@ static void
 gtk_fixed_class_init (GtkFixedClass *klass)
 {
   GtkContainerClass *container_class = GTK_CONTAINER_CLASS (klass);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
 
   container_class->add = gtk_fixed_add;
   container_class->remove = gtk_fixed_remove;
   container_class->forall = gtk_fixed_forall;
   container_class->child_type = gtk_fixed_child_type;
+
+  gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_FIXED_LAYOUT);
 }
 
 static GType
@@ -117,8 +120,7 @@ gtk_fixed_init (GtkFixed *self)
   gtk_widget_set_has_surface (GTK_WIDGET (self), FALSE);
   gtk_widget_set_overflow (GTK_WIDGET (self), GTK_OVERFLOW_HIDDEN);
 
-  priv->layout = gtk_fixed_layout_new ();
+  priv->layout = gtk_widget_get_layout_manager (GTK_WIDGET (self)); 
-  gtk_widget_set_layout_manager (GTK_WIDGET (self), priv->layout);
 }
 
 /**

gtk/gtkgrid.c

@@ -380,6 +380,8 @@ gtk_grid_class_init (GtkGridClass *class)
   g_object_class_install_properties (object_class, N_PROPERTIES, obj_properties);
 
   gtk_widget_class_set_css_name (widget_class, I_("grid"));
+
+  gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_GRID_LAYOUT);
 }
 
 static void
@@ -389,8 +391,7 @@ gtk_grid_init (GtkGrid *grid)
 
   gtk_widget_set_has_surface (GTK_WIDGET (grid), FALSE);
 
-  priv->layout_manager = gtk_grid_layout_new ();
+  priv->layout_manager = gtk_widget_get_layout_manager (GTK_WIDGET (grid));
-  gtk_widget_set_layout_manager (GTK_WIDGET (grid), priv->layout_manager);
 
   priv->orientation = GTK_ORIENTATION_HORIZONTAL;
   _gtk_orientable_set_style_classes (GTK_ORIENTABLE (grid));

gtk/gtkoverlay.c

@@ -302,6 +302,8 @@ gtk_overlay_class_init (GtkOverlayClass *klass)
                   GDK_TYPE_RECTANGLE | G_SIGNAL_TYPE_STATIC_SCOPE);
 
   gtk_widget_class_set_css_name (widget_class, I_("overlay"));
+
+  gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_OVERLAY_LAYOUT);
 }
 
 static void
@@ -311,8 +313,7 @@ gtk_overlay_init (GtkOverlay *overlay)
 
   gtk_widget_set_has_surface (GTK_WIDGET (overlay), FALSE);
 
-  priv->layout = gtk_overlay_layout_new ();
+  priv->layout = gtk_widget_get_layout_manager (GTK_WIDGET (overlay));
-  gtk_widget_set_layout_manager (GTK_WIDGET (overlay), priv->layout);
 }
 
 static GtkBuildableIface *parent_buildable_iface;

gtk/gtkwidget.c

@@ -497,6 +497,7 @@ struct _GtkWidgetClassPrivate
   GType accessible_type;
   AtkRole accessible_role;
   const char *css_name;
+  GType layout_manager_type;
 };
 
 enum {
@@ -2740,6 +2741,7 @@ gtk_widget_init (GTypeInstance *instance, gpointer g_class)
 {
   GtkWidget *widget = GTK_WIDGET (instance);
   GtkWidgetPrivate *priv = gtk_widget_get_instance_private (widget);
+  GType layout_manager_type;
 
   widget->priv = priv;
 
@@ -2808,6 +2810,10 @@ gtk_widget_init (GTypeInstance *instance, gpointer g_class)
 
   if (g_type_is_a (G_TYPE_FROM_CLASS (g_class), GTK_TYPE_ROOT))
     priv->root = (GtkRoot *) widget;
+
+  layout_manager_type = gtk_widget_class_get_layout_manager_type (g_class);
+  if (layout_manager_type != G_TYPE_INVALID)
+    gtk_widget_set_layout_manager (widget, g_object_new (layout_manager_type, NULL));
 }
 
 /**
@@ -13575,6 +13581,52 @@ gtk_widget_get_height (GtkWidget *widget)
   return priv->height;
 }
 
+/**
+ * gtk_widget_class_set_layout_manager_type:
+ * @widget_class: class to set the layout manager type for
+ * @type: The object type that implements the #GtkLayoutManager for @widget_class
+ *
+ * Sets the type to be used for creating layout managers for widgets of
+ * @widget_class. The given @type must be a subtype of #GtkLayoutManager.
+ *
+ * This function should only be called from class init functions of widgets.
+ **/
+void
+gtk_widget_class_set_layout_manager_type (GtkWidgetClass *widget_class,
+                                          GType           type)
+{
+  GtkWidgetClassPrivate *priv;
+
+  g_return_if_fail (GTK_IS_WIDGET_CLASS (widget_class));
+  g_return_if_fail (g_type_is_a (type, GTK_TYPE_LAYOUT_MANAGER));
+
+  priv = widget_class->priv;
+
+  priv->layout_manager_type = type;
+}
+
+/**
+ * gtk_widget_class_get_layout_manager_type:
+ * @widget_class: a #GtkWidgetClass
+ *
+ * Retrieves the type of the #GtkLayoutManager used by the #GtkWidget class.
+ *
+ * See also: gtk_widget_class_set_layout_manager_type()
+ *
+ * Returns: a #GtkLayoutManager subclass, or %G_TYPE_INVALID
+ */
+GType
+gtk_widget_class_get_layout_manager_type (GtkWidgetClass *widget_class)
+{
+  GtkWidgetClassPrivate *priv;
+
+  g_return_val_if_fail (GTK_IS_WIDGET_CLASS (widget_class), G_TYPE_INVALID);
+
+  priv = widget_class->priv;
+
+  return priv->layout_manager_type;
+}
+
 /**
  * gtk_widget_set_layout_manager:
  * @widget: a #GtkWidget

gtk/gtkwidget.h

@@ -414,6 +414,12 @@ void                    gtk_widget_set_layout_manager   (GtkWidget        *widge
 GDK_AVAILABLE_IN_ALL
 GtkLayoutManager *      gtk_widget_get_layout_manager   (GtkWidget        *widget);
 
+GDK_AVAILABLE_IN_ALL
+void                    gtk_widget_class_set_layout_manager_type        (GtkWidgetClass *widget_class,
+                                                                         GType           type);
+GDK_AVAILABLE_IN_ALL
+GType                   gtk_widget_class_get_layout_manager_type        (GtkWidgetClass *widget_class);
+
 GDK_AVAILABLE_IN_ALL
 void       gtk_widget_add_accelerator     (GtkWidget           *widget,
                                            const gchar         *accel_signal,