[meld] Use Alt+Up/Down for Previous/Next diff (closes bgo#626183, bgo#613849)

[Kai Willadsen <kaiw src gnome org>]

commit 0bcbab20550741cff80d57970303877735274a60
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Fri May 7 08:15:06 2010 +1000

    Use Alt+Up/Down for Previous/Next diff (closes bgo#626183, bgo#613849)
    
    GtkSourceView uses two different binding mechanisms; blatant
    interception pre-2.10, and a nice binding post-2.10. We need to deal
    with both.

 meld/meldapp.py           |    4 ++--
 meld/util/sourceviewer.py |   45 ++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 46 insertions(+), 3 deletions(-)
---
diff --git a/meld/meldapp.py b/meld/meldapp.py
index 39bb9a1..040eb9b 100644
--- a/meld/meldapp.py
+++ b/meld/meldapp.py
@@ -154,8 +154,8 @@ class MeldApp(gnomeglade.Component):
             ("Preferences", gtk.STOCK_PREFERENCES, _("Prefere_nces"), None, _("Configure the application"), self.on_menu_preferences_activate),
 
             ("ChangesMenu", None, _("_Changes")),
-            ("NextChange", gtk.STOCK_GO_DOWN, _("Next change"), "<control>D", _("Go to the next change"), self.on_menu_edit_down_activate),
-            ("PrevChange", gtk.STOCK_GO_UP,   _("Previous change"), "<control>E", _("Go to the previous change"), self.on_menu_edit_up_activate),
+            ("NextChange", gtk.STOCK_GO_DOWN, _("Next change"), "<Alt>Down", _("Go to the next change"), self.on_menu_edit_down_activate),
+            ("PrevChange", gtk.STOCK_GO_UP,   _("Previous change"), "<Alt>Up", _("Go to the previous change"), self.on_menu_edit_up_activate),
 
             ("ViewMenu", None, _("_View")),
             ("FileStatus",  None, _("File status")),
diff --git a/meld/util/sourceviewer.py b/meld/util/sourceviewer.py
index f1be1fc..ec97378 100644
--- a/meld/util/sourceviewer.py
+++ b/meld/util/sourceviewer.py
@@ -19,6 +19,9 @@
 
 import os
 
+import gtk
+
+
 class _srcviewer(object):
     # Module name to be imported for the sourceviewer class
     srcviewer_module = None
@@ -152,9 +155,48 @@ class gtksourceview24(_gtksourceview2):
         if self.gsv.pygtksourceview2_version[1] < 4:
             raise ImportError
 
+    def overrides(self):
+        _gtksourceview2.overrides(self)
+        viewClass = self.gsv.View
+
+        class SourceView(viewClass):
+
+            __gsignals__ = {
+                'key-press-event': 'override'
+            }
+
+            def do_key_press_event(self, event):
+                if event.keyval in (gtk.keysyms.KP_Up, gtk.keysyms.KP_Down,
+                                    gtk.keysyms.Up, gtk.keysyms.Down) and \
+                   (event.state & gtk.gdk.MOD1_MASK) != 0 and \
+                   (event.state & gtk.gdk.SHIFT_MASK) == 0:
+                    return True
+                return viewClass.do_key_press_event(self, event)
+
+        self.GtkTextView = SourceView
+
     def get_language_from_file(self, filename):
         return self.get_language_manager().guess_language(filename)
 
+
+class gtksourceview210(gtksourceview24):
+
+    def version_check(self):
+        if self.gsv.pygtksourceview2_version[1] < 10:
+            raise ImportError
+
+    def overrides(self):
+        _gtksourceview2.overrides(self)
+        gtk.binding_entry_remove(self.GtkTextView, gtk.keysyms.Up,
+                                 gtk.gdk.MOD1_MASK)
+        gtk.binding_entry_remove(self.GtkTextView, gtk.keysyms.KP_Up,
+                                 gtk.gdk.MOD1_MASK)
+        gtk.binding_entry_remove(self.GtkTextView, gtk.keysyms.Down,
+                                 gtk.gdk.MOD1_MASK)
+        gtk.binding_entry_remove(self.GtkTextView, gtk.keysyms.KP_Down,
+                                 gtk.gdk.MOD1_MASK)
+
+
 class nullsourceview(_srcviewer):
     """Implement the sourceviewer API when no real one is available
     """
@@ -181,7 +223,8 @@ class nullsourceview(_srcviewer):
         pass
 
 def _get_srcviewer():
-    for srcv in (gtksourceview24, gtksourceview22, gtksourceview, sourceview):
+    for srcv in (gtksourceview210, gtksourceview24, gtksourceview22,
+                 gtksourceview, sourceview):
         try:
             return srcv()
         except ImportError: