[gnome-tweak-tool] Single instance of gnome tweak tool

[John Stowers <jstowers src gnome org>]

commit 646cde92932e80512c14f2cb602a18fe35f3264a
Author: Alex Muñoz <alexmudoz gmail com>
Date:   Sun Jul 28 02:13:43 2013 -0400

    Single instance of gnome tweak tool

 gtweak/app.py |   25 ++++++++++++++-----------
 1 files changed, 14 insertions(+), 11 deletions(-)
---
diff --git a/gtweak/app.py b/gtweak/app.py
index b33e190..530f858 100644
--- a/gtweak/app.py
+++ b/gtweak/app.py
@@ -31,18 +31,21 @@ class GnomeTweakTool(Gtk.Application):
 
     def __init__(self):
         Gtk.Application.__init__(self,application_id="org.gnome.TweakTool")
-    
-    def do_activate(self):                                           
-        self.win = self.builder.get_object('main_window')
-        self.win.set_position(Gtk.WindowPosition.CENTER)
-        self.win.set_application(self)
-        self.win.set_size_request(720, 580)
+        self.win = None
+
+    def do_activate(self):
+        if not self.win:
+            self.win = self.builder.get_object('main_window')
+            self.win.set_position(Gtk.WindowPosition.CENTER)
+            self.win.set_application(self)
+            self.win.set_size_request(720, 580)
         
-        model = TweakModel()
-        view = TweakView(self.builder, model)
-        
-        self.win.show_all()
-        view.run()
+            model = TweakModel()
+            view = TweakView(self.builder, model)
+            
+            self.win.show_all()
+            view.run()
+        self.win.present()
         
     def do_startup(self):
         Gtk.Application.do_startup(self)