Drag and drop from the navigator to the viewframes now work.

system/plots.py

@@ -59,6 +59,13 @@ class ViewFrame (gtk.Frame):
         else:
             self.unfocus()
 
+        # Get dropped views
+        self.drag_dest_set(gtk.DEST_DEFAULT_ALL,
+                           [("GTK_TREE_MODEL_ROW", gtk.TARGET_SAME_APP, 7)],
+                           gtk.gdk.ACTION_LINK)
+        self.connect("drag-data-received", self.on_drag_data_received)
+       
+
         # Set view
         self._view = self.empty_view
         self._view.connect("button-press-event", self.on_button_press_event)
@@ -79,7 +86,7 @@ class ViewFrame (gtk.Frame):
         return self
 
     def unfocus(self):
-        """Removes focus from the ViewFrame if it is focused."""
+        """Removes focus from the ViewFrame. Does nothing if unfocused."""
         if not self.focused:
             return
 
@@ -88,6 +95,7 @@ class ViewFrame (gtk.Frame):
 
     def set_view(self, view):
         """Set view to view or to empty view if parameter is None"""
+
         # if None is passed, use empty view
         if view == None:
             view = self.empty_view
@@ -104,6 +112,7 @@ class ViewFrame (gtk.Frame):
         # switch which widget we are listening to
         if self._button_event:
             self._view.disconnect(self._button_event)
+
         self._button_event = view.connect("button-press-event", self.on_button_press_event)
 
         # remove old view, set new view
@@ -124,6 +133,14 @@ class ViewFrame (gtk.Frame):
         if not self.focused:
             self.focus()
             
+    def on_drag_data_received(self, widget, drag_context, x, y, selection, info, timestamp):
+        treestore, path = selection.tree_get_row_drag_data()
+        iter = treestore.get_iter(path)
+        obj  = treestore.get_value(iter,2)
+        if isinstance(obj, Plot):
+            self.set_view(obj)
+
+
 class MainView (gtk.Notebook):
     def __init__(self):
         gtk.Notebook.__init__(self)