Django学习笔记之二

一、使用Django自带的后端管理平台

１、后台创建管理员

python manage.py createsuperuser

Email address: admin@example.com

Password: **********
Password (again): *********
Superuser created successfully.

２、打开后台页面

http://127.0.0.1:8000/admin/

输入刚才的用户名及密码登陆：

此时还看不到我们刚才创建的数据表

那我们打开polls/admin.py文件，把我们所创建的数据表配置进去后台，可以通过修改models.py / admin.py代码来设置多种显示格式，其中一种如下：

from django.contrib import admin
from polls.models import Choice, Question

class ChoiceInline(admin.StackedInline):
    model = Choice
    extra = 3

class QuestionAdmin(admin.ModelAdmin):
    fieldsets = [
        (None,               {'fields': ['question_text']}),
        ('Date information', {'fields': ['pub_date'], 'classes': ['collapse']}),
    ]
    inlines = [ChoiceInline]

admin.site.register(Question, QuestionAdmin)

二、自定义模板

先在polls文件夹下方创建一个名叫templates的目录，再修改如下配置文件，把目录添加到系统路径

mysite/settings.py

TEMPLATE_DIRS = [os.path.join(BASE_DIR, 'templates')]

各种template如下：

templates/polls/index.html

{% load staticfiles %}
<link rel="stylesheet" type="text/css" href="{% static 'polls/style.css' %}" />
{% if latest_question_list %}
  <ul>
      {% for question in latest_question_list %}
          <li><a href="{% url 'polls:detail' question.id %}">{{ question.question_text }}</a></li>
      {% endfor %}
  </ul>
{% else %}
  <p>No polls are available.</p>
{% endif %}

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>

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>

三、创建视图

polls/views.py

from django.shortcuts import render,get_object_or_404
from django.http import HttpResponseRedirect,HttpResponse
from django.core.urlresolvers import reverse
from django.views import generic
from django.utils import timezone

from polls.models import Choice, Question

# Create your views here.

class IndexView(generic.ListView):
    template_name='polls/index.html'
    context_object_name='latest_question_list'

    def get_queryset(self):
        """Return the last five published question"""
        return Question.objects.filter(
            pub_date__lte=timezone.now()
        ).order_by('-pub_date')[:5]

class DetailView(generic.DetailView):
    model = Question
    template_name = 'polls/detail.html'
    def get_queryset(self):
        return Question.objects.filter(pub_date__lte=timezone.now())

class ResultsView(generic.DetailView):
    model=Question
    template_name = 'polls/results.html'

def vote(request, question_id):
    p=get_object_or_404(Question,pk=question_id)
    try:
        selected_choice=p.choice_set.get(pk=request.POST['choice'])
    except (KeyError, Choice.DoesNotExist):
        return render(request,'polls/detail.html',{
            'question':p,
            'error_message':"You didn't select a choice",
            })
    else:
        selected_choice.votes += 1
        selected_choice.save()
    return HttpResponseRedirect(reverse('polls:results',args=(p.id,)))

mysite/urls.py   总的url配置

from django.conf.urls import patterns, include, url
from django.contrib import admin

urlpatterns = patterns('',
    url(r'^polls/', include('polls.urls',namespace="polls")),
    url(r'^admin/', include(admin.site.urls)),
)

polls/urls.py　　子url配置

from django.conf.urls import patterns,url
from polls import views

urlpatterns=patterns('',
    url(r'^$',views.IndexView.as_view(),name='index'),
    url(r'^(?P<pk>\d+)/$',views.DetailView.as_view(),name='detail'),
    url(r'^(?P<pk>\d+)/results/$',views.ResultsView.as_view(),name='results'),
    url(r'^(?P<question_id>\d+)/vote/$',views.vote,name='vote'),
)

四、最终Models如下：

polls/models.py

import datetime
from django.db import models
from django.utils import timezone
# Create your models here.

class Question(models.Model):
    question_text = models.CharField(max_length=200)
    pub_date = models.DateTimeField('date published')
    def __str__(self):
        return self.question_text
    def was_published_recently(self):
        now = timezone.now()
        return now >= self.pub_date >= now - datetime.timedelta(days=1)
    was_published_recently.admin_order_field='pub_date'
    was_published_recently.bollean = True
    was_published_recently.short_description='Published recently?'

class Choice(models.Model):
    question = models.ForeignKey(Question)
    choice_text = models.CharField(max_length=200)
    votes = models.IntegerField(default=0)
    def __str__(self):
        return self.choice_text

五、自定义样式/静态文件位置配置，在polls文件夹下面创建static文件夹

静态文件如：polls/static/polls/style.css

mysite/settings.py　文件中应有下面的默认配置，如果没有，手动添加

# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.7/howto/static-files/

STATIC_URL = '/static/'
#STATIC_URL = [os.path.join(BASE_DIR,'static')]