gui: Extend the GcalView interface with a method to redraw the weekday layout

Part-of: <https://gitlab.gnome.org/GNOME/gnome-calendar/-/merge_requests/822>

src/gui/gcal-window.c

@@ -729,6 +729,15 @@ on_window_undo_delete_event_cb (GSimpleAction *action,
   GCAL_EXIT;
 }
 
+static void
+on_week_start_day_changed_cb (GcalWindow *self)
+{
+  g_assert (GCAL_IS_WINDOW (self));
+
+  for (size_t i = 0; i < GCAL_WINDOW_VIEW_N_VIEWS; ++i)
+    gcal_view_first_weekday_changed (GCAL_VIEW (self->views[i]));
+}
+
 static void
 on_breakpoint_changed (GObject *object,
                        GParamSpec *pspec,
@@ -1497,6 +1506,11 @@ gcal_window_init (GcalWindow *self)
                    G_SETTINGS_BIND_SET | G_SETTINGS_BIND_GET);
 
   g_signal_connect (self->agenda_page, "notify::visible", G_CALLBACK (on_agenda_page_visible_changed_cb), self);
+
+  g_signal_connect_object (context, "notify::week-start-day",
+                           G_CALLBACK (on_week_start_day_changed_cb),
+                           self,
+                           G_CONNECT_SWAPPED);
 }
 
 /**

src/gui/views/gcal-view.c

@@ -294,3 +294,12 @@ gcal_view_event_activated (GcalView        *self,
 
   g_signal_emit (self, signals[EVENT_ACTIVATED], 0, event_widget);
 }
+
+void
+gcal_view_first_weekday_changed (GcalView *self)
+{
+  g_assert (GCAL_IS_VIEW (self));
+  g_assert (GCAL_VIEW_GET_IFACE (self)->first_weekday_changed != NULL);
+
+  GCAL_VIEW_GET_IFACE (self)->first_weekday_changed (self);
+}

src/gui/views/gcal-view.h

@@ -57,6 +57,8 @@ struct _GcalViewInterface
   GList*             (*get_children_by_uuid)                     (GcalView              *view,
                                                                   GcalRecurrenceModType  mod,
                                                                   const gchar           *uuid);
+
+  void               (*first_weekday_changed)                    (GcalView           *view);
 };
 
 void                 gcal_view_set_date                          (GcalView           *view,
@@ -76,4 +78,6 @@ GDateTime*           gcal_view_get_next_date                     (GcalView
 
 GDateTime*           gcal_view_get_previous_date                 (GcalView              *self);
 
+void                 gcal_view_first_weekday_changed             (GcalView              *self);
+
 G_END_DECLS