Question

I’m trying to return filtered values from a m2m relationship to use in a template. Should be trivial, but I can’t get it to work.

I tried to do it in the model as described here and didn’t get it to work. Now I’m trying a potentially easier way in the view, described here, but can’t get it to work either.

class Activity(models.Model):
    activity_nm = models.CharField(max_length=60)  
    enddt = models.DateField()
    groups =  models.ManyToManyField(Group)
    def __unicode__(self):
        return self.activity_nm     

class Group (models.Model):
    group_nm = models.CharField(max_length=64)
    def __unicode__(self):
        return self.group_nm        



def group_details_page(request, group_nm):
    g=Activity.objects.filter(groups__in=[Group.objects.filter(group_nm=group_nm)],enddt__gt=now)
    return render_to_response('group_details_page.html', {'group': g},context_instance=RequestContext(request))   

My goal is to return all activities for one group where the activity’s end date > now to be available in the template.

Thanks.

EDIT: There error received is:
int() argument must be a string or a number, not ‘QuerySet’

EDIT2: It looks like there is more to this problem than I thought. I can’t get any values to return now.

g=Group.objects.all()

does not return values to the template. The template resolves the base.html call, but trying to get just {{ group.group_nm }} to appear does not work.

EDIT3: Got it to return group names (sorry for the confusion).

Answer 1

Tested it and the solution is really simple.

With g=Activity.objects.filter(groups__in=[Group.objects.filter(group_nm=group_nm)],enddt__gt=now) you put an iterable in a list ([QuerySet]) which django doesn’t know how to index.

The solution is to dump the list comprehension:

g=Activity.objects.filter(groups__in=Group.objects.filter(group_nm=group_nm),enddt__gt=now)

and then it works like a charm.