Set vertical/horizontal class on all widgets overriding GtkOrientable::orientation

This is so g_object_set() on that property leaves widgets' style in
a meaningful state. Fully fixes bug 639157.

1 files changed, 13 insertions, 0 deletions

diff --git a/gtk/gtkgrid.c b/gtk/gtkgrid.c
index 3557c16949..525f970df6 100644
--- a/gtk/gtkgrid.c
+++ b/gtk/gtkgrid.c
@@ -187,10 +187,23 @@ gtk_grid_set_orientation (GtkGrid        *grid,
                           GtkOrientation  orientation)
 {
   GtkGridPrivate *priv = grid->priv;
+  GtkStyleContext *context;
 
   if (priv->orientation != orientation)
     {
       priv->orientation = orientation;
+      context = gtk_widget_get_style_context (GTK_WIDGET (grid));
+
+      if (grid->priv->orientation == GTK_ORIENTATION_VERTICAL)
+        {
+          gtk_style_context_add_class (context, GTK_STYLE_CLASS_VERTICAL);
+          gtk_style_context_remove_class (context, GTK_STYLE_CLASS_HORIZONTAL);
+        }
+      else
+        {
+          gtk_style_context_add_class (context, GTK_STYLE_CLASS_HORIZONTAL);
+          gtk_style_context_remove_class (context, GTK_STYLE_CLASS_VERTICAL);
+        }
 
       g_object_notify (G_OBJECT (grid), "orientation");
     }