eventcontrollerscroll: Conditionally propagate ::scrollscroll-event-propagation

Currently, gtk_event_controller_scroll_handle_event() always returns
TRUE if it is handled, which stops the propagation of the event. If
there’s a single GtkEventControllerScroll in the widget hierarchy, that
means that no others will run, depending on the propagation phase. In
Nautilus, this can be observed when adding a scroll controller to the
GtkScrolledWindow (ctrl-scrolling controls the zoom level) - either the
scrolling or the zooming breaks.

Fixes https://gitlab.gnome.org/GNOME/gtk/issues/45

1 files changed, 4 insertions, 2 deletions

diff --git a/gtk/gtkmenu.c b/gtk/gtkmenu.c
index 1efbb2ed4d..d73f2df91d 100644
--- a/gtk/gtkmenu.c
+++ b/gtk/gtkmenu.c
@@ -247,7 +247,7 @@ static void     gtk_menu_grab_notify       (GtkWidget        *widget,
 static gboolean gtk_menu_captured_event    (GtkWidget        *widget,
                                             GdkEvent         *event);
 
-static void     gtk_menu_scroll_controller_scroll (GtkEventControllerScroll *scroll,
+static gboolean gtk_menu_scroll_controller_scroll (GtkEventControllerScroll *scroll,
                                                    gdouble                   dx,
                                                    gdouble                   dy,
                                                    GtkMenu                  *menu);
@@ -3211,13 +3211,15 @@ gtk_menu_scroll_timeout (gpointer data)
   return TRUE;
 }
 
-static void
+static gboolean
 gtk_menu_scroll_controller_scroll (GtkEventControllerScroll *scroll,
                                    gdouble                   dx,
                                    gdouble                   dy,
                                    GtkMenu                  *menu)
 {
   gtk_menu_scroll_by (menu, dy * MENU_SCROLL_STEP2);
+
+  return TRUE;
 }
 
 static void