Initial prototype.

* Changed database to introduce Citations
* Introduced new Citation Primary object and CitationBase (equivalent to CitationRef) child object
* Implemented CitationTreeModel and CitationListModel
* Implemented CitationTreeView and CitationListView for new citation views in the navigator
* Implemented EditCitation which is used both for the citation views in the navigator and for the citations of an object
* Implemented the CitationEmbedList to display the citations of an object
* Modified the bottom bar gramplets to support citations
* Implemented the citation selector.
* Modified Media object to include references to Citations
* Initial work on deleting citations


svn: r17960

src/plugins/gramplet/Backlinks.py

@@ -1,6 +1,7 @@
 # Gramps - a GTK+/GNOME based genealogy program
 #
 # Copyright (C) 2011 Nick Hall
+# Copyright (C) 2011 Tim G L Lyons
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -172,6 +173,27 @@ class SourceBacklinks(Backlinks):
         else:
             self.set_has_data(False)
 
+class CitationBacklinks(Backlinks):
+    """
+    Displays the back references for a Citation,.
+    """
+    def db_changed(self):
+        self.dbstate.db.connect('citation-update', self.update)
+        self.connect_signal('Citation', self.update)
+        self.update()
+
+    def update_has_data(self):
+        active_handle = self.get_active('Citation')
+        self.set_has_data(self.get_has_data(active_handle))
+    
+    def main(self):
+        active_handle = self.get_active('Citation')
+        self.model.clear()
+        if active_handle:
+            self.display_backlinks(active_handle)
+        else:
+            self.set_has_data(False)
+
 class RepositoryBacklinks(Backlinks):
     """
     Displays the back references for a repository.