[meld/CompChange: 3/3] Add sensitivity handling for tab actions

[Kai Willadsen <kaiw src gnome org>]

commit 6836e3202ec3d86bdbee2346add8661c2f8c0e56
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sat Mar 5 14:39:45 2011 +1000

    Add sensitivity handling for tab actions

 data/ui/meldapp.ui |    1 +
 meld/meldwindow.py |   13 +++++++++++++
 2 files changed, 14 insertions(+), 0 deletions(-)
---
diff --git a/data/ui/meldapp.ui b/data/ui/meldapp.ui
index 49d8c7f..80135d3 100644
--- a/data/ui/meldapp.ui
+++ b/data/ui/meldapp.ui
@@ -21,6 +21,7 @@
             <signal handler="_update_notebook_menu" name="page-added"/>
             <signal handler="_update_notebook_menu" name="page-removed"/>
             <signal handler="_update_notebook_menu" name="page-reordered"/>
+            <signal handler="after_page_reordered" name="page-reordered" after="True"/>
           </object>
           <packing>
             <property name="position">1</property>
diff --git a/meld/meldwindow.py b/meld/meldwindow.py
index 2336301..e83ba2d 100644
--- a/meld/meldwindow.py
+++ b/meld/meldwindow.py
@@ -302,6 +302,15 @@ class MeldWindow(gnomeglade.Component):
     def on_delete_event(self, *extra):
         return self.on_menu_quit_activate()
 
+    def _update_page_action_sensitivity(self):
+        current_page = self.notebook.get_current_page()
+        have_prev_tab = current_page > 0
+        have_next_tab = current_page < self.notebook.get_n_pages() - 1
+        self.actiongroup.get_action("PrevTab").set_sensitive(have_prev_tab)
+        self.actiongroup.get_action("NextTab").set_sensitive(have_next_tab)
+        self.actiongroup.get_action("MoveTabPrev").set_sensitive(have_prev_tab)
+        self.actiongroup.get_action("MoveTabNext").set_sensitive(have_next_tab)
+
     def on_switch_page(self, notebook, page, which):
         newdoc = notebook.get_nth_page(which).get_data("pyobject")
         newseq = newdoc.undosequence
@@ -321,11 +330,15 @@ class MeldWindow(gnomeglade.Component):
         self.scheduler.add_task( newdoc.scheduler )
 
     def after_switch_page(self, notebook, page, which):
+        self._update_page_action_sensitivity()
         actiongroup = self.tab_switch_actiongroup
         if actiongroup:
             action_name = "SwitchTab%d" % which
             actiongroup.get_action(action_name).set_active(True)
 
+    def after_page_reordered(self, notebook, page, page_num):
+        self._update_page_action_sensitivity()
+
     def on_notebook_label_changed(self, component, text, tooltip):
         page = component.widget
         nbl = self.notebook.get_tab_label(page)