[gnome-clocks/wip/headerbar: 2/2] Fix crash

[Stefano Facchini <sfacchini src gnome org>]

commit 20c34964b128b8d495ad10c785509e69f6465d00
Author: Stefano Facchini <stefano facchini gmail com>
Date:   Fri Mar 8 15:14:09 2013 +0100

    Fix crash

 src/widgets.vala |   19 ++++++++++++++-----
 1 files changed, 14 insertions(+), 5 deletions(-)
---
diff --git a/src/widgets.vala b/src/widgets.vala
index b9027a9..182b15a 100644
--- a/src/widgets.vala
+++ b/src/widgets.vala
@@ -28,6 +28,8 @@ public class Toolbar : Gd.HeaderBar {
     private List<Gtk.Widget> buttons;
     private Gd.StackSwitcher stack_switcher;
 
+    private bool realized = false;
+
     [CCode (notify = false)]
     public Mode mode {
         get {
@@ -35,7 +37,7 @@ public class Toolbar : Gd.HeaderBar {
         }
 
         set {
-            if (_mode != value) {
+            if (_mode != value && realized) {
                 _mode = value;
 
                 custom_title = (_mode == Mode.NORMAL) ? stack_switcher : null;
@@ -53,12 +55,19 @@ public class Toolbar : Gd.HeaderBar {
 
     private Mode _mode;
 
+    construct {
+        stack_switcher = new Gd.StackSwitcher ();
+        realize.connect (() => {
+            realized = true;
+            custom_title = stack_switcher;
+       });
+       unrealize.connect (() => {
+           realized = false;
+        });
+    }
+
     public void set_stack (Gd.Stack stack) {
-        if (stack_switcher == null) {
-            stack_switcher = new Gd.StackSwitcher ();
-        }
         stack_switcher.set_stack (stack);
-        custom_title = stack_switcher;
     }
 
     public Gtk.Button add_button (string? icon_name, string? label, bool should_pack_start) {