GtkMenuButton: Support popovers

Add api to allow explicitly setting a GtkPopover instead of
a GtkMenu as the popup of a GtkMenuButton. Also, add api to
instruct the menu button to construct a popover when given
a menu model.

We set the style class "menu-button" on the button only when
it pops up a menu, to allow different treatment for the active
state of the button in the two cases.

https://bugzilla.gnome.org/show_bug.cgi?id=723878

2 files changed, 360 insertions, 100 deletions

diff --git a/gtk/gtkmenubutton.c b/gtk/gtkmenubutton.c
index dbce31b631..c79cebeae8 100644
--- a/gtk/gtkmenubutton.c
+++ b/gtk/gtkmenubutton.c
@@ -20,25 +20,28 @@
 
 /**
  * SECTION:gtkmenubutton
- * @short_description: A widget that shows a menu when clicked on
+ * @short_description: A widget that shows a popup when clicked on
  * @title: GtkMenuButton
  *
- * The #GtkMenuButton widget is used to display a menu when clicked on.
- * This menu can be provided either as a #GtkMenu, or an abstract #GMenuModel.
+ * The #GtkMenuButton widget is used to display a popup when clicked on.
+ * This popup can be provided either as a #GtkMenu, a #GtkPopover or an
+ * abstract #GMenuModel.
  *
  * The #GtkMenuButton widget can hold any valid child widget. That is, it
  * can hold almost any other standard #GtkWidget. The most commonly used
  * child is the provided #GtkArrow.
  *
- * The positioning of the menu is determined by the #GtkMenuButton:direction
- * property of the menu button and the #GtkWidget:halign or #GtkWidget:valign
- * properties of the menu. For example, when the direction is %GTK_ARROW_DOWN
- * and the horizontal alignment is %GTK_ALIGN_START, the menu will be
- * positioned below the button, with the starting edge (depending on the
- * text direction) of the menu aligned with the starting edge of the button.
- * If there is not enough space below the button, the menu is popped up above
- * the button instead. If the alignment would move part of the menu offscreen,
- * it is “pushed in”.
+ * The positioning of the popup is determined by the #GtkMenuButton:direction
+ * property of the menu button.
+ *
+ * For menus, the #GtkWidget:halign and #GtkWidget:valign properties of the
+ * menu are also taken into account. For example, when the direction is
+ * %GTK_ARROW_DOWN and the horizontal alignment is %GTK_ALIGN_START, the
+ * menu will be positioned below the button, with the starting edge
+ * (depending on the text direction) of the menu aligned with the starting
+ * edge of the button. If there is not enough space below the button, the
+ * menu is popped up above the button instead. If the alignment would move
+ * part of the menu offscreen, it is “pushed in”.
  *
  * ## Direction = Down
  *
@@ -107,6 +110,7 @@
 #include "gtkwindow.h"
 #include "gtkmain.h"
 #include "gtkaccessible.h"
+#include "gtkpopover.h"
 #include "a11y/gtkmenubuttonaccessible.h"
 
 #include "gtkprivate.h"
@@ -114,7 +118,8 @@
 
 struct _GtkMenuButtonPrivate
 {
-  GtkWidget *popup;
+  GtkWidget *menu;    /* The menu and the popover are mutually exclusive */
+  GtkWidget *popover; /* Only one at a time can be set */
   GMenuModel *model;
 
   GtkMenuButtonShowMenuCallback func;
@@ -123,6 +128,7 @@ struct _GtkMenuButtonPrivate
   GtkWidget *align_widget;
   gpointer arrow_widget;
   GtkArrowType arrow_type;
+  gboolean use_popover;
 };
 
 enum
@@ -131,7 +137,9 @@ enum
   PROP_POPUP,
   PROP_MODEL,
   PROP_ALIGN_WIDGET,
-  PROP_DIRECTION
+  PROP_DIRECTION,
+  PROP_USE_POPOVER,
+  PROP_POPOVER
 };
 
 G_DEFINE_TYPE_WITH_PRIVATE (GtkMenuButton, gtk_menu_button, GTK_TYPE_TOGGLE_BUTTON)
@@ -160,6 +168,12 @@ gtk_menu_button_set_property (GObject      *object,
       case PROP_DIRECTION:
         gtk_menu_button_set_direction (self, g_value_get_enum (value));
         break;
+      case PROP_USE_POPOVER:
+        gtk_menu_button_set_use_popover (self, g_value_get_boolean (value));
+        break;
+      case PROP_POPOVER:
+        gtk_menu_button_set_popover (self, g_value_get_object (value));
+        break;
       default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
     }
@@ -176,7 +190,7 @@ gtk_menu_button_get_property (GObject    *object,
   switch (property_id)
     {
       case PROP_POPUP:
-        g_value_set_object (value, priv->popup);
+        g_value_set_object (value, priv->menu);
         break;
       case PROP_MODEL:
         g_value_set_object (value, priv->model);
@@ -187,6 +201,12 @@ gtk_menu_button_get_property (GObject    *object,
       case PROP_DIRECTION:
         g_value_set_enum (value, priv->arrow_type);
         break;
+      case PROP_USE_POPOVER:
+        g_value_set_boolean (value, priv->use_popover);
+        break;
+      case PROP_POPOVER:
+        g_value_set_object (value, priv->popover);
+        break;
       default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
     }
@@ -199,8 +219,13 @@ gtk_menu_button_state_flags_changed (GtkWidget    *widget,
   GtkMenuButton *button = GTK_MENU_BUTTON (widget);
   GtkMenuButtonPrivate *priv = button->priv;
 
-  if (!gtk_widget_is_sensitive (widget) && priv->popup)
-    gtk_menu_shell_deactivate (GTK_MENU_SHELL (priv->popup));
+  if (!gtk_widget_is_sensitive (widget))
+    {
+      if (priv->menu)
+        gtk_menu_shell_deactivate (GTK_MENU_SHELL (priv->menu));
+      else if (priv->popover)
+        gtk_widget_hide (priv->popover);
+    }
 }
 
 static void
@@ -227,11 +252,11 @@ menu_position_up_down_func (GtkMenu       *menu,
    */
   if (priv->arrow_type == GTK_ARROW_DOWN)
     {
-      toplevel = gtk_widget_get_toplevel (GTK_WIDGET (priv->popup));
+      toplevel = gtk_widget_get_toplevel (priv->menu);
       gtk_window_set_type_hint (GTK_WINDOW (toplevel), GDK_WINDOW_TYPE_HINT_DROPDOWN_MENU);
     }
 
-  align = gtk_widget_get_halign (GTK_WIDGET (priv->popup));
+  align = gtk_widget_get_halign (priv->menu);
   direction = gtk_widget_get_direction (widget);
   window = gtk_widget_get_window (priv->align_widget ? priv->align_widget : widget);
 
@@ -243,7 +268,7 @@ menu_position_up_down_func (GtkMenu       *menu,
 
   gtk_widget_get_allocation (priv->align_widget ? priv->align_widget : widget, &allocation);
   gtk_widget_get_allocation (widget, &arrow_allocation);
-  gtk_widget_get_allocation (GTK_WIDGET (priv->popup), &menu_allocation);
+  gtk_widget_get_allocation (priv->menu, &menu_allocation);
 
   gdk_window_get_origin (window, x, y);
   *x += allocation.x;
@@ -311,7 +336,7 @@ menu_position_side_func (GtkMenu       *menu,
   gdk_window_get_origin (gtk_button_get_event_window (GTK_BUTTON (menu_button)), x, y);
 
   gtk_widget_get_allocation (widget, &allocation);
-  gtk_widget_get_allocation (GTK_WIDGET (priv->popup), &menu_allocation);
+  gtk_widget_get_allocation (priv->menu, &menu_allocation);
 
   if ((priv->arrow_type == GTK_ARROW_RIGHT && direction == GTK_TEXT_DIR_LTR) ||
       (priv->arrow_type == GTK_ARROW_LEFT && direction == GTK_TEXT_DIR_RTL))
@@ -352,7 +377,7 @@ popup_menu (GtkMenuButton  *menu_button,
   if (priv->func)
     priv->func (priv->user_data);
 
-  if (!priv->popup)
+  if (!priv->menu)
     return;
 
   switch (priv->arrow_type)
@@ -366,7 +391,7 @@ popup_menu (GtkMenuButton  *menu_button,
         break;
   }
 
-  gtk_menu_popup_for_device (GTK_MENU (priv->popup),
+  gtk_menu_popup_for_device (GTK_MENU (priv->menu),
                              event ? event->device : NULL,
                              NULL, NULL,
                              func,
@@ -382,27 +407,38 @@ gtk_menu_button_toggled (GtkToggleButton *button)
   GtkMenuButton *menu_button = GTK_MENU_BUTTON (button);
   GtkMenuButtonPrivate *priv = menu_button->priv;
 
-  if (!priv->popup)
+  if (!gtk_toggle_button_get_active (button))
     return;
 
-  if (gtk_toggle_button_get_active (button) &&
-      !gtk_widget_get_visible (GTK_WIDGET (priv->popup)))
-    {
-      /* we get here only when the menu is activated by a key
-       * press, so that we can select the first menu item
-       */
-      popup_menu (menu_button, NULL);
-      gtk_menu_shell_select_first (GTK_MENU_SHELL (priv->popup), FALSE);
+  if (priv->menu)
+    {  
+      if (!gtk_widget_get_visible (priv->menu))
+        {
+          /* we get here only when the menu is activated by a key
+           * press, so that we can select the first menu item
+           */
+          popup_menu (menu_button, NULL);
+          gtk_menu_shell_select_first (GTK_MENU_SHELL (priv->menu), FALSE);
+        }
     }
+  else if (priv->popover)
+    gtk_widget_show (priv->popover); 
 }
 
 static gboolean
 gtk_menu_button_button_press_event (GtkWidget      *widget,
                                     GdkEventButton *event)
 {
+  GtkMenuButton *menu_button = GTK_MENU_BUTTON (widget);
+  GtkMenuButtonPrivate *priv = menu_button->priv;
+
   if (event->button == GDK_BUTTON_PRIMARY)
     {
-      popup_menu (GTK_MENU_BUTTON (widget), event);
+      if (priv->menu)
+        popup_menu (menu_button, event);
+      else if (priv->popover)
+        gtk_widget_show (priv->popover);
+
       gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (widget), TRUE);
 
       return TRUE;
@@ -473,7 +509,10 @@ gtk_menu_button_class_init (GtkMenuButtonClass *klass)
   /**
    * GtkMenuButton:menu-model:
    *
-   * The #GMenuModel from which the menu to pop up will be created.
+   * The #GMenuModel from which the popup will be created.
+   * Depending on the #GtkMenuButton:use-popover property, that may
+   * be a menu or a popover.
+   *
    * See gtk_menu_button_set_menu_model() for the interaction with the
    * #GtkMenuButton:popup property.
    *
@@ -483,13 +522,13 @@ gtk_menu_button_class_init (GtkMenuButtonClass *klass)
                                    PROP_MODEL,
                                    g_param_spec_object ("menu-model",
                                                         P_("Menu model"),
-                                                        P_("The dropdown menu's model."),
+                                                        P_("The model from which the popup is made."),
                                                         G_TYPE_MENU_MODEL,
                                                         G_PARAM_READWRITE));
   /**
    * GtkMenuButton:align-widget:
    *
-   * The #GtkWidget to use to align the popup menu with.
+   * The #GtkWidget to use to align the menu with.
    *
    * Since: 3.6
    */
@@ -504,7 +543,7 @@ gtk_menu_button_class_init (GtkMenuButtonClass *klass)
    * GtkMenuButton:direction:
    *
    * The #GtkArrowType representing the direction in which the
-   * menu will be popped out.
+   * menu or popover will be popped out.
    *
    * Since: 3.6
    */
@@ -516,6 +555,37 @@ gtk_menu_button_class_init (GtkMenuButtonClass *klass)
                                                       GTK_TYPE_ARROW_TYPE,
                                                       GTK_ARROW_DOWN,
                                                       G_PARAM_READWRITE));
+  /**
+   * GtkMenuButton:use-popover:
+   *
+   * Whether to construct a #GtkPopover from the menu model,
+   * or a #GtkMenu.
+   *
+   * Since: 3.12
+   */
+  g_object_class_install_property (gobject_class,
+                                   PROP_USE_POPOVER,
+                                   g_param_spec_boolean ("use-popover",
+                                                         P_("Use a popover"),
+                                                         P_("Use a popover instead of a menu"),
+                                                         FALSE,
+                                                         G_PARAM_READWRITE));
+
+  /**
+   * GtkMenuButton:popover:
+   *
+   * The #GtkPopover that will be popped up when the button is clicked.
+   *
+   * Since: 3.12
+   */
+  g_object_class_install_property (gobject_class,
+                                   PROP_POPOVER,
+                                   g_param_spec_object ("popover",
+                                                        P_("Popover"),
+                                                        P_("The popover"),
+                                                        GTK_TYPE_POPOVER,
+                                                        G_PARAM_READWRITE));
+
 
   gtk_widget_class_set_accessible_type (widget_class, GTK_TYPE_MENU_BUTTON_ACCESSIBLE);
 }
@@ -557,7 +627,7 @@ gtk_menu_button_init (GtkMenuButton *menu_button)
  * arrow as the only child. You can replace the child widget
  * with another #GtkWidget should you wish to.
  *
- * Returns: The newly created #GtkMenuButton widget.
+ * Returns: The newly created #GtkMenuButton widget
  *
  * Since: 3.6
  */
@@ -570,10 +640,10 @@ gtk_menu_button_new (void)
 /* Callback for the "deactivate" signal on the pop-up menu.
  * This is used so that we unset the state of the toggle button
  * when the pop-up menu disappears.
+ * Also used for the "close" signal on the popover.
  */
-static int
-menu_deactivate_cb (GtkMenuShell  *menu_shell,
-                    GtkMenuButton *menu_button)
+static gboolean
+menu_deactivate_cb (GtkMenuButton *menu_button)
 {
   gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (menu_button), FALSE);
 
@@ -586,9 +656,9 @@ menu_detacher (GtkWidget *widget,
 {
   GtkMenuButtonPrivate *priv = GTK_MENU_BUTTON (widget)->priv;
 
-  g_return_if_fail (priv->popup == (GtkWidget *) menu);
+  g_return_if_fail (priv->menu == (GtkWidget *) menu);
 
-  priv->popup = NULL;
+  priv->menu = NULL;
 }
 
 /* This function is used in GtkMenuToolButton, the call back will
@@ -610,36 +680,32 @@ _gtk_menu_button_set_popup_with_func (GtkMenuButton                 *menu_button
   priv->func = func;
   priv->user_data = user_data;
 
-  if (priv->popup == GTK_WIDGET (menu))
+  if (priv->menu == GTK_WIDGET (menu))
     return;
 
-  if (priv->popup)
+  if (priv->menu)
     {
-      if (gtk_widget_get_visible (GTK_WIDGET (priv->popup)))
-        gtk_menu_shell_deactivate (GTK_MENU_SHELL (priv->popup));
+      if (gtk_widget_get_visible (priv->menu))
+        gtk_menu_shell_deactivate (GTK_MENU_SHELL (priv->menu));
 
-      g_signal_handlers_disconnect_by_func (priv->popup,
+      g_signal_handlers_disconnect_by_func (priv->menu,
                                             menu_deactivate_cb,
                                             menu_button);
-      gtk_menu_detach (GTK_MENU (priv->popup));
+      gtk_menu_detach (GTK_MENU (priv->menu));
     }
 
-  priv->popup = menu;
+  priv->menu = menu;
 
-  if (priv->popup)
+  if (priv->menu)
     {
-      gtk_menu_attach_to_widget (GTK_MENU (priv->popup), GTK_WIDGET (menu_button),
+      gtk_menu_attach_to_widget (GTK_MENU (priv->menu), GTK_WIDGET (menu_button),
                                  menu_detacher);
 
-      gtk_widget_set_visible (priv->popup, FALSE);
-      gtk_widget_set_sensitive (GTK_WIDGET (menu_button), TRUE);
+      gtk_widget_set_visible (priv->menu, FALSE);
 
-      g_signal_connect (priv->popup, "deactivate",
-                        G_CALLBACK (menu_deactivate_cb), menu_button);
-    }
-  else
-    {
-      gtk_widget_set_sensitive (GTK_WIDGET (menu_button), FALSE);
+      g_signal_connect_swapped (priv->menu, "deactivate",
+                                G_CALLBACK (menu_deactivate_cb), menu_button);
+      gtk_style_context_add_class (gtk_widget_get_style_context (GTK_WIDGET (menu_button)), "menu-button");
     }
 
   g_object_notify (G_OBJECT (menu_button), "popup");
@@ -649,27 +715,32 @@ _gtk_menu_button_set_popup_with_func (GtkMenuButton                 *menu_button
 /**
  * gtk_menu_button_set_popup:
  * @menu_button: a #GtkMenuButton
- * @popup: (allow-none): a #GtkMenu
+ * @menu: (allow-none): a #GtkMenu
  *
  * Sets the #GtkMenu that will be popped up when the button is clicked,
- * or %NULL to disable the button. If #GtkMenuButton:menu-model is set,
- * it will be set to %NULL.
+ * or %NULL to disable the button. If #GtkMenuButton:menu-model or
+ * #GtkMenuButton:popover are set, they will be set to %NULL.
  *
  * Since: 3.6
  */
 void
 gtk_menu_button_set_popup (GtkMenuButton *menu_button,
-                           GtkWidget     *popup)
+                           GtkWidget     *menu)
 {
-  GtkMenuButtonPrivate *priv;
+  GtkMenuButtonPrivate *priv = menu_button->priv;
 
   g_return_if_fail (GTK_IS_MENU_BUTTON (menu_button));
-  g_return_if_fail (GTK_IS_MENU (popup) || popup == NULL);
+  g_return_if_fail (GTK_IS_MENU (menu) || menu == NULL);
 
-  priv = menu_button->priv;
   g_clear_object (&priv->model);
 
-  _gtk_menu_button_set_popup_with_func (menu_button, popup, NULL, NULL);
+  _gtk_menu_button_set_popup_with_func (menu_button, menu, NULL, NULL);
+
+  if (menu && priv->popover)
+    gtk_menu_button_set_popover (menu_button, NULL);
+
+  gtk_widget_set_sensitive (GTK_WIDGET (menu_button),
+                            priv->menu != NULL || priv->popover != NULL);
 }
 
 /**
@@ -677,8 +748,10 @@ gtk_menu_button_set_popup (GtkMenuButton *menu_button,
  * @menu_button: a #GtkMenuButton
  *
  * Returns the #GtkMenu that pops out of the button.
+ * If the button does not use a #GtkMenu, this function
+ * returns %NULL.
  *
- * Returns: (transfer none): a #GtkMenu or %NULL.
+ * Returns: (transfer none): a #GtkMenu or %NULL
  *
  * Since: 3.6
  */
@@ -687,7 +760,7 @@ gtk_menu_button_get_popup (GtkMenuButton *menu_button)
 {
   g_return_val_if_fail (GTK_IS_MENU_BUTTON (menu_button), NULL);
 
-  return GTK_MENU (menu_button->priv->popup);
+  return GTK_MENU (menu_button->priv->menu);
 }
 
 /**
@@ -695,14 +768,16 @@ gtk_menu_button_get_popup (GtkMenuButton *menu_button)
  * @menu_button: a #GtkMenuButton
  * @menu_model: (allow-none): a #GMenuModel
  *
- * Sets the #GMenuModel from which the #GtkMenuButton:popup property will be
- * filled in, or %NULL to disable the button.
+ * Sets the #GMenuModel from which the popup will be constructed,
+ * or %NULL to disable the button.
  *
- * The #GtkMenu will be created with gtk_menu_new_from_model(), so actions
- * will be connected as documented there.
+ * Depending on the value of #GtkMenuButton:use-popover, either a
+ * #GtkMenu will be created with gtk_menu_new_from_model(), or a
+ * #GtkPopover with gtk_popover_new_from_model(). In either case,
+ * actions will be connected as documented for these functions.
  *
- * If #GtkMenuButton:popup is already set, then its content will be lost
- * and replaced by our newly created #GtkMenu.
+ * If #GtkMenuButton:popup or #GtkMenuButton:popover are already set,
+ * their content will be lost and replaced by the newly created popup.
  *
  * Since: 3.6
  */
@@ -711,33 +786,45 @@ gtk_menu_button_set_menu_model (GtkMenuButton *menu_button,
                                 GMenuModel    *menu_model)
 {
   GtkMenuButtonPrivate *priv;
-  GtkWidget *menu;
 
   g_return_if_fail (GTK_IS_MENU_BUTTON (menu_button));
   g_return_if_fail (G_IS_MENU_MODEL (menu_model) || menu_model == NULL);
 
   priv = menu_button->priv;
+
   g_clear_object (&priv->model);
+  gtk_menu_button_set_popup (menu_button, NULL);
+  gtk_menu_button_set_popover (menu_button, NULL);
 
   if (menu_model == NULL)
+    return;
+
+  priv->model = g_object_ref (menu_model);
+
+  if (priv->use_popover)
     {
-      gtk_menu_button_set_popup (menu_button, NULL);
-      return;
+      GtkWidget *popover;
+
+      popover = gtk_popover_new_from_model (GTK_WIDGET (menu_button), menu_model);
+      gtk_menu_button_set_popover (menu_button, popover);
     }
+  else
+    {
+      GtkWidget *menu;
 
-  priv->model = g_object_ref (menu_model);
-  menu = gtk_menu_new_from_model (menu_model);
-  gtk_widget_show_all (menu);
-  gtk_menu_button_set_popup (menu_button, menu);
+      menu = gtk_menu_new_from_model (menu_model);
+      gtk_widget_show_all (menu);
+      gtk_menu_button_set_popup (menu_button, menu);
+    }
 }
 
 /**
  * gtk_menu_button_get_menu_model:
  * @menu_button: a #GtkMenuButton
  *
- * Returns the #GMenuModel used to generate the menu.
+ * Returns the #GMenuModel used to generate the popup.
  *
- * Returns: (transfer none): a #GMenuModel or %NULL.
+ * Returns: (transfer none): a #GMenuModel or %NULL
  *
  * Since: 3.6
  */
@@ -771,12 +858,15 @@ set_align_widget_pointer (GtkMenuButton *menu_button,
  * @menu_button: a #GtkMenuButton
  * @align_widget: (allow-none): a #GtkWidget
  *
- * Sets the #GtkWidget to use to line the menu with when popped up. Note that
- * the @align_widget must contain the #GtkMenuButton itself.
+ * Sets the #GtkWidget to use to line the menu with when popped up.
+ * Note that the @align_widget must contain the #GtkMenuButton itself.
  *
- * Setting it to %NULL means that the popup menu will be aligned with the
+ * Setting it to %NULL means that the menu will be aligned with the
  * button itself.
  *
+ * Note that this property is only used with menus currently,
+ * and not for popovers.
+ *
  * Since: 3.6
  */
 void
@@ -803,7 +893,7 @@ gtk_menu_button_set_align_widget (GtkMenuButton *menu_button,
  *
  * Returns the parent #GtkWidget to use to line up with menu.
  *
- * Returns: (transfer none): a #GtkWidget value or %NULL.
+ * Returns: (transfer none): a #GtkWidget value or %NULL
  *
  * Since: 3.6
  */
@@ -815,19 +905,45 @@ gtk_menu_button_get_align_widget (GtkMenuButton *menu_button)
   return menu_button->priv->align_widget;
 }
 
+static void
+update_popover_direction (GtkMenuButton *menu_button)
+{
+  GtkMenuButtonPrivate *priv = menu_button->priv;
+
+  if (!priv->popover)
+    return;
+
+  switch (priv->arrow_type)
+    {
+    case GTK_ARROW_UP:
+      gtk_popover_set_position (GTK_POPOVER (priv->popover), GTK_POS_TOP);
+      break;
+    case GTK_ARROW_DOWN:
+    case GTK_ARROW_NONE:
+      gtk_popover_set_position (GTK_POPOVER (priv->popover), GTK_POS_BOTTOM);
+      break;
+    case GTK_ARROW_LEFT:
+      gtk_popover_set_position (GTK_POPOVER (priv->popover), GTK_POS_LEFT);
+      break;
+    case GTK_ARROW_RIGHT:
+      gtk_popover_set_position (GTK_POPOVER (priv->popover), GTK_POS_RIGHT);
+      break;
+    }
+}
+
 /**
  * gtk_menu_button_set_direction:
  * @menu_button: a #GtkMenuButton
  * @direction: a #GtkArrowType
  *
- * Sets the direction in which the menu will be popped up, as
+ * Sets the direction in which the popup will be popped up, as
  * well as changing the arrow’s direction. The child will not
  * be changed to an arrow if it was customized.
  *
- * If the menu when popped out would have collided with screen edges,
- * we will do our best to keep it inside the screen and fully visible.
+ * If the does not fit in the available space in the given direction,
+ * GTK+ will its best to keep it inside the screen and fully visible.
  *
- * If you pass %GTK_ARROW_NONE for a @direction, the menu will behave
+ * If you pass %GTK_ARROW_NONE for a @direction, the popup will behave
  * as if you passed %GTK_ARROW_DOWN (although you won’t see any arrows).
  *
  * Since: 3.6
@@ -852,15 +968,17 @@ gtk_menu_button_set_direction (GtkMenuButton *menu_button,
     return;
 
   gtk_arrow_set (GTK_ARROW (child), priv->arrow_type, GTK_SHADOW_NONE);
+
+  update_popover_direction (menu_button);
 }
 
 /**
  * gtk_menu_button_get_direction:
  * @menu_button: a #GtkMenuButton
  *
- * Returns the direction the menu will be pointing at when popped up.
+ * Returns the direction the popup will be pointing at when popped up.
  *
- * Returns: a #GtkArrowType value.
+ * Returns: a #GtkArrowType value
  *
  * Since: 3.6
  */
@@ -877,13 +995,19 @@ gtk_menu_button_dispose (GObject *object)
 {
   GtkMenuButtonPrivate *priv = GTK_MENU_BUTTON (object)->priv;
 
-  if (priv->popup)
+  if (priv->menu)
     {
-      g_signal_handlers_disconnect_by_func (priv->popup,
+      g_signal_handlers_disconnect_by_func (priv->menu,
                                             menu_deactivate_cb,
                                             object);
-      gtk_menu_detach (GTK_MENU (priv->popup));
-      priv->popup = NULL;
+      gtk_menu_detach (GTK_MENU (priv->menu));
+      priv->menu = NULL;
+    }
+
+  if (priv->popover)
+    {
+      gtk_widget_destroy (priv->popover);
+      priv->popover = NULL;
     }
 
   set_align_widget_pointer (GTK_MENU_BUTTON (object), NULL);
@@ -892,3 +1016,124 @@ gtk_menu_button_dispose (GObject *object)
 
   G_OBJECT_CLASS (gtk_menu_button_parent_class)->dispose (object);
 }
+
+/**
+ * gtk_menu_button_set_use_popover:
+ * @menu_button: a #GtkMenuButton
+ * @use_popover: %TRUE to construct a popover from the menu model
+ *
+ * Sets whether to construct a #GtkPopover instead of #GtkMenu
+ * when gtk_menu_button_set_menu_model() is called. Note that
+ * this property is only consulted when a new menu model is set.
+ *
+ * Since: 3.12
+ */
+void
+gtk_menu_button_set_use_popover (GtkMenuButton *menu_button,
+                                 gboolean       use_popover)
+{
+  GtkMenuButtonPrivate *priv;
+
+  g_return_if_fail (GTK_IS_MENU_BUTTON (menu_button));
+
+  priv = menu_button->priv;
+
+  use_popover = use_popover != FALSE;
+
+  if (priv->use_popover == use_popover)
+    return;
+
+  priv->use_popover = use_popover;
+
+  g_object_notify (G_OBJECT (menu_button), "use-popover");
+}
+
+/**
+ * gtk_menu_button_get_use_popover:
+ * @menu_button: a #GtkMenuButton
+ *
+ * Returns whether a #GtkPopover or a #GtkMenu will be constructed
+ * from the menu model.
+ *
+ * Return value: %TRUE if using a #GtkPopover
+ *
+ * Since: 3.12
+ */
+gboolean
+gtk_menu_button_get_use_popover (GtkMenuButton *menu_button)
+{
+  g_return_val_if_fail (GTK_IS_MENU_BUTTON (menu_button), FALSE);
+
+  return menu_button->priv->use_popover;
+}
+
+/**
+ * gtk_menu_button_set_popover:
+ * @menu_button: a #GtkMenuButton
+ * @popover: (allow-none): a #GtkPopover
+ *
+ * Sets the #GtkPopover that will be popped up when the button is
+ * clicked, or %NULL to disable the button. If #GtkMenuButton:menu-model
+ * or #GtkMenuButton:popup are set, they will be set to %NULL.
+ *
+ * Since: 3.12
+ */
+void
+gtk_menu_button_set_popover (GtkMenuButton *menu_button,
+                             GtkWidget     *popover)
+{
+  GtkMenuButtonPrivate *priv = menu_button->priv;
+
+  g_return_if_fail (GTK_IS_MENU_BUTTON (menu_button));
+  g_return_if_fail (GTK_IS_POPOVER (popover) || popover == NULL);
+
+  g_clear_object (&priv->model);
+
+  if (priv->popover)
+    {
+      if (gtk_widget_get_visible (priv->popover))
+        gtk_widget_hide (priv->popover);
+
+      g_signal_handlers_disconnect_by_func (priv->popover,
+                                            menu_deactivate_cb,
+                                            menu_button);
+      gtk_popover_set_relative_to (GTK_POPOVER (priv->popover), NULL);
+    }
+
+  priv->popover = popover;
+
+  if (popover)
+    {
+      gtk_popover_set_relative_to (GTK_POPOVER (priv->popover), GTK_WIDGET (menu_button));
+      g_signal_connect_swapped (priv->popover, "closed",
+                                G_CALLBACK (menu_deactivate_cb), menu_button);
+      update_popover_direction (menu_button);
+      gtk_style_context_remove_class (gtk_widget_get_style_context (GTK_WIDGET (menu_button)), "menu-button");
+    }
+
+  if (popover && priv->menu)
+    gtk_menu_button_set_popup (menu_button, NULL);
+
+  gtk_widget_set_sensitive (GTK_WIDGET (menu_button),
+                            priv->menu != NULL || priv->popover != NULL);
+}
+
+/**
+ * gtk_menu_button_get_popover:
+ * @menu_button: a #GtkMenuButton
+ *
+ * Returns the #GtkPopover that pops out of the button.
+ * If the button is not using a #GtkPopover, this function
+ * returns %NULL.
+ *
+ * Returns: (transfer none): a #GtkPopover or %NULL
+ *
+ * Since: 3.12
+ */
+GtkPopover *
+gtk_menu_button_get_popover (GtkMenuButton *menu_button)
+{
+  g_return_val_if_fail (GTK_IS_MENU_BUTTON (menu_button), NULL);
+
+  return GTK_POPOVER (menu_button->priv->popover);
+}
diff --git a/gtk/gtkmenubutton.h b/gtk/gtkmenubutton.h
index 8aa2644cd2..82a876b606 100644
--- a/gtk/gtkmenubutton.h
+++ b/gtk/gtkmenubutton.h
@@ -27,6 +27,7 @@
 
 #include <gtk/gtktogglebutton.h>
 #include <gtk/gtkmenu.h>
+#include <gtk/gtkpopover.h>
 
 G_BEGIN_DECLS
 
@@ -67,10 +68,16 @@ GtkWidget   *gtk_menu_button_new            (void);
 
 GDK_AVAILABLE_IN_3_6
 void         gtk_menu_button_set_popup      (GtkMenuButton *menu_button,
-                                             GtkWidget     *popup);
+                                             GtkWidget     *menu);
 GDK_AVAILABLE_IN_3_6
 GtkMenu     *gtk_menu_button_get_popup      (GtkMenuButton *menu_button);
 
+GDK_AVAILABLE_IN_3_12
+void         gtk_menu_button_set_popover    (GtkMenuButton *menu_button,
+                                             GtkWidget     *popover);
+GDK_AVAILABLE_IN_3_12
+GtkPopover  *gtk_menu_button_get_popover    (GtkMenuButton *menu_button);
+
 GDK_AVAILABLE_IN_3_6
 void         gtk_menu_button_set_direction  (GtkMenuButton *menu_button,
                                              GtkArrowType   direction);
@@ -89,6 +96,14 @@ void         gtk_menu_button_set_align_widget (GtkMenuButton *menu_button,
 GDK_AVAILABLE_IN_3_6
 GtkWidget   *gtk_menu_button_get_align_widget (GtkMenuButton *menu_button);
 
+GDK_AVAILABLE_IN_3_12
+void         gtk_menu_button_set_use_popover (GtkMenuButton *menu_button,
+                                              gboolean       use_popover);
+
+GDK_AVAILABLE_IN_3_12
+gboolean     gtk_menu_button_get_use_popover (GtkMenuButton *menu_button);
+
+
 G_END_DECLS
 
 #endif /* __GTK_MENU_BUTTON_H__ */