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Python Django Class-based Views Customizing Class-based Views Custom Mixin

Posted by osk junior
osk junior
Courses Plus Student 2,020 Points

??12

Why do I get error in this solution?

articles/views.py 
from django.contrib.auth.mixins import LoginRequiredMixin
from django.core.urlresolvers import reverse_lazy
from django.views import generic

from . import mixins
from . import models


class ArticleList(generic.ListView):
    model = models.Article


class ArticleDetail(generic.DeleteView, generic.DetailView):
    model = models.Article
    template_name = 'articles/article_detail.html'


class ArticleCreate(LoginRequiredMixin, mixins.SuccessMessageMixin, generic.CreateView):
    fields = ('title', 'body', 'author', 'published')
    model = models.Article
    success_message = "Article created! "

class ArticleUpdate(LoginRequiredMixin, mixins.SuccessMessageMixin, generic.UpdateView):
    fields = ('title', 'body', 'author', 'published')
    model = models.Article

    def get_success_message(self):
        obj = self.get_object()
        return  "{} updated!".format(obj.title)
class ArticleDelete(LoginRequiredMixin, generic.DeleteView):
    model = models.Article
    success_url = reverse_lazy('articles:list')


class ArticleSearch(generic.ListView):
    model = models.Article

    def get_queryset(self):
        qs = super().get_queryset()
        term = self.kwargs.get('term')
        if term:
            return qs.filter(body__icontains=term)
        return qs.none()
articles/mixins.py 
from django.contrib import messages

class SuccessMessageMixin:
    success_message=""


    def get_success_message(self):
        return self.success_message

    def form_valid(self,form):
        form(self.request.POST)

        if super().form_valid(form):
            messages.success(self.get_success_message())

        return super()

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,454 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,454 Points

Only two steps are needed in the overridden form_valid method:

  • set success message, and
  • call the parent method using super()

"Overriding" parent method but do nothing new looks like:

    def form_valid(self, form):
        # local version override
        # call parent method
        super().form_valid(form)

The only step would be to add updating the message.success using self.request and self.get_success_message

    def form_valid(self, form):
        # local version override
        message.success(self.request, self.get_success_message())
        # call parent method
        super().form_valid(form)

Post back if you have more questions. Good luck!!