GtkTextHandle: Look up for the first child of a scrolled window found

Text handles use to connect to the first GtkScrollable up the hierarchy
so they can be repositioned when scrolling. It makes more sense to look
up the first child of a GtkScrolledWindow, it must be an scrollable too,
and will be the scrollable that can actually change the position of the
text handles.

https://bugzilla.gnome.org/show_bug.cgi?id=761676

diff --git a/gtk/gtktexthandle.c b/gtk/gtktexthandle.c
index 5ed6ebce31cd6d10db9bc0eed2b3bd9809acf0ea..cc98d226a01217ebc9d4c170375bd37c601311cf 100644 (file)
--- a/gtk/gtktexthandle.c
+++ b/gtk/gtktexthandle.c
@@ -544,6 +544,21 @@ _gtk_text_handle_update_scrollable (GtkTextHandle *handle,
                         handle);
 }
 
+static GtkWidget *
+gtk_text_handle_lookup_scrollable (GtkTextHandle *handle)
+{
+  GtkTextHandlePrivate *priv;
+  GtkWidget *scrolled_window;
+
+  priv = handle->priv;
+  scrolled_window = gtk_widget_get_ancestor (priv->parent,
+                                             GTK_TYPE_SCROLLED_WINDOW);
+  if (!scrolled_window)
+    return NULL;
+
+  return gtk_bin_get_child (GTK_BIN (scrolled_window));
+}
+
 static void
 _gtk_text_handle_parent_hierarchy_changed (GtkWidget     *widget,
                                            GtkWindow     *previous_toplevel,
@@ -574,7 +589,7 @@ _gtk_text_handle_parent_hierarchy_changed (GtkWidget     *widget,
         }
     }
 
-  scrollable = gtk_widget_get_ancestor (widget, GTK_TYPE_SCROLLABLE);
+  scrollable = gtk_text_handle_lookup_scrollable (handle);
   _gtk_text_handle_update_scrollable (handle, GTK_SCROLLABLE (scrollable));
 }
 
@@ -603,7 +618,7 @@ _gtk_text_handle_set_parent (GtkTextHandle *handle,
                           G_CALLBACK (_gtk_text_handle_parent_hierarchy_changed),
                           handle);
 
-      scrollable = gtk_widget_get_ancestor (parent, GTK_TYPE_SCROLLABLE);
+      scrollable = gtk_text_handle_lookup_scrollable (handle);
     }
 
   _gtk_text_handle_update_scrollable (handle, GTK_SCROLLABLE (scrollable));