python之尝试在详细 View 中覆盖模板名称时出现 TemplateDoesNotExist

我正在关注 django 2.0 教程“2.6.2 使用通用 View :代码越少越好”，并尝试将函数 View 转换为类 View 。

它抛出这样的错误:

TemplateDoesNotExist at /polls/1/results/ 
polls/question_detail.html 
Request Method: GET 
Request URL:    http://127.0.0.1:8000/polls/1/results/ 
Django Version: 2.0.4 

我用官方资料查了一下代码

class ResultsView(generic.DetailView): 
    model = Question 
    template = 'polls/results.html' 
 
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 did'nt select a choice.", 
        }) 
    else: 
        selected_choice.votes += 1 
        selected_choice.save() 
        return HttpResponseRedirect(reverse('polls:results', args=(question.id,))) 

当我尝试提交投票时出现错误:

polls/detail.html 模板在带有函数 View 时可以正常工作:

<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> 

我的代码有什么问题？

请您参考如下方法:

默认情况下，polls 应用中Question 模型的DetailView 使用模板polls/question_detail.html.

如果你想覆盖它，你需要使用 template_name。您已经设置了template，这不会有任何效果。应该是:

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