============= > Numerous clever workarounds are given in the forums but I decided to > try using "formfield_for_manytomany" in the inline class. This works > brilliantly. ============== Make that "...using formfield_for_foreignkey() in the inline class." !!! (Rushing to go for a coffee!)
On Aug 16, 9:52 am, DelS <[email protected]> wrote: > I am fairly new and using Django Admin to manage a set of lists and > forms for a database GUI. > I am not happy with the performance rendering a form which has > foreignkey fields or manytomany fields with numerous values. This > inspired me to get involved with overloading > "formfield_for_foreignkey" which I eventually managed. > When I went to tackle a "manytomany" formfield for an 'inline' the > "admin" doco says "use 'formfield_for_manytomany' as usual, so I > created the approriate method in the 'inline' Class but it was never > invoked. > Numerous clever workarounds are given in the forums but I decided to > try using "formfield_for_manytomany" in the inline class. This works > brilliantly. > I guess the principle is that within the "through" model, the fields > are actually "foreignkey" fields, and the 'db_field.name' values > correspond to that model. > > Here is a fragment of code where I cache the queryset for multiple > fields in the session dictionary. > > #--------------------------------------------- > # use inline feature in Route for Points and Tracks > class PointsInline(TabularInline): > model = Route.points.through > extra = 0 > > class TracksInline(TabularInline): > def formfield_for_foreignkey( self,db_field, request, **kwargs): > if db_field.name == "track_id" or db_field.name == "point_id": > url_split = request.path.split('/') > route_id = url_split[-2] > try: > previous_id = request.session.get("RouteId") > except: > previous_id = None > if route_id <> previous_id : > print db_field.name, request.path, "\n" > request.session["RouteId"] = route_id > q_line = > Route.objects.get(id=route_id).from_signal.location.line > tq_set = Track.objects.filter(location__line=q_line) > request.session["TrackList"] = tq_set > pq_set = Point.objects.filter(location__line=q_line) > request.session["PointList"] = pq_set > print q_line, tq_set.count(), pq_set.count() > if db_field.name == "track_id": > q_set = request.session["TrackList"] > else: > q_set = request.session["PointList"] > kwargs["queryset"] = q_set > return super(TracksInline, > self).formfield_for_foreignkey(db_field, request, **kwargs ) > else: > return None > model = Route.tracks.through > extra = 0 > > class RouteAdmin(ModelAdmin): > inlines = [ PointsInline, TracksInline ] > list_per_page = 48 > list_display = > ('__unicode__','from_signal','to_signal','direction') > list_filter= ('to_signal__location__line',) > exclude = ('tracks','points',) > search_fields = > ('to_signal__location__vcode','from_signal__location__vcode',) > #--------------------------------------------- -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
