[gitg] Make sure to unbind from settings when closing preferences

[Jesse van den Kieboom <jessevdk src gnome org>]

commit 5023d3304e480c64faa7663f7d9a51117176b4c4
Author: Jesse van den Kieboom <jessevdk gmail com>
Date:   Sun Dec 14 10:05:23 2014 +0100

    Make sure to unbind from settings when closing preferences

 gitg/preferences/gitg-preferences-interface.vala |   33 ++++++++++++++++------
 1 files changed, 24 insertions(+), 9 deletions(-)
---
diff --git a/gitg/preferences/gitg-preferences-interface.vala 
b/gitg/preferences/gitg-preferences-interface.vala
index a1287a2..69f36ad 100644
--- a/gitg/preferences/gitg-preferences-interface.vala
+++ b/gitg/preferences/gitg-preferences-interface.vala
@@ -26,15 +26,16 @@ public class PreferencesInterface : Gtk.Grid, GitgExt.Preferences
        // Do this to pull in config.h before glib.h (for gettext...)
        private const string version = Gitg.Config.VERSION;
        private bool d_block;
+       private Settings? d_settings;
 
        [GtkChild (name = "horizontal_layout_enabled")]
        private Gtk.CheckButton d_horizontal_layout_enabled;
 
        construct
        {
-               var settings = new Settings("org.gnome.gitg.preferences.interface");
+               d_settings = new Settings("org.gnome.gitg.preferences.interface");
 
-               d_horizontal_layout_enabled.active = settings.get_enum("orientation") == 0;
+               d_horizontal_layout_enabled.active = d_settings.get_enum("orientation") == 0;
 
                d_horizontal_layout_enabled.notify["active"].connect((obj, spec)=> {
                        if (d_block)
@@ -42,17 +43,31 @@ public class PreferencesInterface : Gtk.Grid, GitgExt.Preferences
                                return;
                        }
 
-                       if (!settings.set_enum("orientation", d_horizontal_layout_enabled.active ? 0 : 1))
+                       if (!d_settings.set_enum("orientation", d_horizontal_layout_enabled.active ? 0 : 1))
                        {
-                               d_horizontal_layout_enabled.active = settings.get_enum("orientation") == 0;
+                               d_horizontal_layout_enabled.active = d_settings.get_enum("orientation") == 0;
                        }
                });
 
-               settings.changed["orientation"].connect((s, k) => {
-                       d_block = true;
-                       d_horizontal_layout_enabled.active = settings.get_enum("orientation") == 0;
-                       d_block = false;
-               });
+               d_settings.changed["orientation"].connect(orientation_changed);
+       }
+
+       public override void dispose()
+       {
+               if (d_settings != null)
+               {
+                       d_settings.changed["orientation"].disconnect(orientation_changed);
+                       d_settings = null;
+               }
+
+               base.dispose();
+       }
+
+       private void orientation_changed(Settings settings, string key)
+       {
+               d_block = true;
+               d_horizontal_layout_enabled.active = settings.get_enum(key) == 0;
+               d_block = false;
        }
 
        public Gtk.Widget widget