Writing your first Django app, part 4¶
4-1. Forms¶
Lab:
*** edit polls/urls.py
*** edit polls/views.py
*** edit polls/templates/polls/detail.html
*** add polls/templates/polls/vote.html
*** add polls/templates/polls/result.html
. go
polls/urls.py:
from django.urls import path from . import views app_name = 'polls' urlpatterns = [ path('', views.index, name='index'), path('<int:question_id>/', views.detail, name='detail'), path('<int:question_id>/vote/', views.vote, name='vote'), path('<int:question_id>/results/', views.results, name='results'), ]
polls/views.py:
from django.http import HttpResponse, HttpResponseRedirect from django.shortcuts import get_object_or_404, render from django.urls import reverse from .models import Choice, Question def index(request): latest_question_list = Question.objects.order_by('-pub_date')[:5] context = {'latest_question_list': latest_question_list} return render(request, 'polls/index.html', context) def detail(request, question_id): question = get_object_or_404(Question, pk=question_id) return render(request, 'polls/detail.html', {'question': question}) def vote(request, question_id): question = get_object_or_404(Question, pk=question_id) try: selected_choice = question.choice_set.get(pk=request.POST['choice']) except (KeyError, Choice.DoesNotExist): # Redisplay the question voting form. return render(request, 'polls/detail.html', { 'question': question, 'error_message': "You didn't select a choice.", }) else: selected_choice.votes += 1 selected_choice.save() # Always return an HttpResponseRedirect after successfully dealing # with POST data. This prevents data from being posted twice if a # user hits the Back button. return HttpResponseRedirect(reverse('polls:results', args=(question.id,))) def results(request, question_id): question = get_object_or_404(Question, pk=question_id) return render(request, 'polls/results.html', {'question': question})
polls/templates/polls/detail.html:
<h1>{{ question.question_text }}</h1> {% if error_message %}<p><strong>{{ error_message }}</strong></p>{% endif %} <form action="{% url 'polls:vote' question.id %}" method="post"> {% csrf_token %} {% for choice in question.choice_set.all %} <input type="radio" name="choice" id="choice{{ forloop.counter }}" value="{{ choice.id }}"> <label for="choice{{ forloop.counter }}">{{ choice.choice_text }}</label><br> {% endfor %} <input type="submit" value="Vote"> </form>
polls/templates/polls/results.html:
<h1>{{ question.question_text }}</h1> <ul> {% for choice in question.choice_set.all %} <li>{{ choice.choice_text }} -- {{ choice.votes }} vote{{ choice.votes|pluralize }}</li> {% endfor %} </ul> <a href="{% url 'polls:detail' question.id %}">Vote again?</a>
Note
Able to vote