python之'RadioSelect' 对象没有属性 'renderer'_编程设计

我看了django教程做了一个网站。 https://docs.djangoproject.com/en/1.11/intro/

我遇到了一个错误，

AttributeError at /polls/1/ 
'RadioSelect' object has no attribute 'renderer'

它发生在forms.py的第21行，也就是init。我在 forms.py 中这样写

from django import forms 
 
class MyForm(forms.Form): 
    text = forms.CharField(max_length=100,required=False,label='テキスト') 
 
class VoteForm(forms.Form): 
    choice = forms.ModelChoiceField( 
        queryset=None, 
        label='選択', 
        widget=forms.RadioSelect, 
        empty_label=None, 
        error_messages={ 
            'required':"You didn't select a choice.", 
            'invalid_choice':"invalid choice.", 
        }, 
    ) 
 
    def __init__(self,question,*args,**kwargs): 
        super().__init__(*args,**kwargs) 
        self.fields['choice'].queryset = question.choice_set.all() 
        self.fields['choice'].widget.renderer.inner_html = '{choice_value}{sub_widgets}<br>'

radio button的设置写在detail.html,like

<!DOCTYPE html> 
<h1>{{ question.question_text }}</h1> 
{% if error_message %}<p><strong>{{ error_message }}</strong></p>{% endif %} 
 
<form action="{% url 'poll_vote' question.id %}" method="post"> 
<!--<form action="" 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 %} 
    <!--{{ form }}--> 
    <input type="submit" value="Vote" /> 
</form> 
</html>

views.py 是

from django.shortcuts import render 
from django.utils.html import mark_safe 
from .models import Question 
from django.http import HttpResponse 
from django.shortcuts import Http404 
from django.shortcuts import get_object_or_404,redirect 
from .models import Choice 
from django.views.generic import TemplateView 
from django.views.generic import DetailView 
from django.views.generic import ListView 
from .forms import MyForm 
from .forms import VoteForm 
 
 
# Create your views here. 
def index(request): 
    return render(request,'polls/index.html',{ 
        'questions': Question.objects.all(), 
    }) 
 
def detail(request,pk): 
    obj = get_object_or_404(Question,pk=pk) 
    if request.method == "POST": 
        form = VoteForm(question=obj,data=request.POST) 
        if form.is_valid(): 
            return redirect('polls:results',pk) 
    else: 
        form = VoteForm(question=obj) 
    return render(request,'templates/polls/detail.html',{ 
        'form':form, 
        'question': obj, 
    }) 
 
def vote(request,pk): 
    pass 
 
def results(request,pk): 
    obj = get_object_or_404(Question,pk=pk) 
    return render(request,'polls/results.html',{ 
        'question':obj, 
    }) 
 
def form_test(request): 
    if request.method == "POST": 
        #request.POST??? 
        form = MyForm(data=request.POST) 
        if form.is_valid(): 
            pass 
    else: 
        form = MyForm() 
    return render(request,'polls/form.html',{ 
        'form':form, 
    })

回溯就像

Traceback: File "/Users/XXX/django/django/core/handlers/exception.py" in inner 35. response = get_response(request) File "/Users/XXX/django/django/core/handlers/base.py" in _get_response 130. response = self.process_exception_by_middleware(e, request)  
File "/Users/XXX/django/django/core/handlers/base.py" in _get_response 128. response = wrapped_callback(request, *callback_args, **callback_kwargs) File "/Users/XXX/djangostudy/polls/views.py" in detail 40. form = VoteForm(question=obj) File "/Users/XXXi/djangostudy/polls/forms.py" in init 21. self.fields['choice'].widget.renderer.inner_html = '{choice_value}{sub_widgets}<br>' Exception Type: AttributeError at /polls/1/ Exception Value: 'RadioSelect' object has no attribute 'renderer'

我不知道如何修复它。我无法理解为什么会发生此错误。我应该怎么做才能解决这个问题？

请您参考如下方法:

你会看到我们在这里有什么:

>>> from django import forms 
>>> from myapp.models import Vote 
>>>  
>>> class VoteForm(forms.Form): 
...     choice = forms.ModelChoiceField( 
...             queryset=Vote.objects.all(), 
...             widget=forms.RadioSelect() 
...     ) 
...  
>>>  
>>> f = VoteForm() 
>>>  
>>> f.fields['choice'] 
<django.forms.models.ModelChoiceField object at 0xb64ec3ec> 
>>> 
>>> f.fields['choice'].widget.renderer 
Traceback (most recent call last): 
  File "<console>", line 1, in <module> 
AttributeError: 'RadioSelect' object has no attribute 'renderer' 
>>>

您得到回溯 AttributeError: 'RadioSelect' object has no attribute 'renderer' 因为 renderer 不可用:

>>> dir(f.fields['choice'].widget) 
['__class__', '__deepcopy__', '__delattr__', '__dict__', '__dir__', 
'__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', 
'__gt__', '__hash__', '__init__', '__le__', '__lt__', '__module__', 
'__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', 
'__setattr__', '__sizeof__', '__slotnames__', '__str__',  
'__subclasshook__', '__weakref__', '_format_value', '_render',  
'add_id_index', 'allow_multiple_selected', 'attrs', 'build_attrs', 
'checked_attribute', 'choices', 'create_option', 'format_value', 
'get_context', 'id_for_label', 'input_type', 'is_hidden', 'is_localized', 
'is_required', 'media', 'needs_multipart_form', 'optgroups',  
'option_inherits_attrs', 'option_template_name', 'options', 'render', 
'subwidgets', 'supports_microseconds', 'template_name', 
'use_required_attribute', 'value_from_datadict', 'value_omitted_from_data'] 
>>>

但是在这里我们找到了render和_render函数:

>>> f.fields['choice'].widget.render 
<bound method Widget.render of <django.forms.widgets.RadioSelect object at 0xb64ec4ac>> 
>>>  
>>> f.fields['choices'].widget._render 
<bound method Widget._render of <django.forms.widgets.RadioSelect object at 0xb64ec4ac>> 
>>>

I just don't know why you need this function .inner_html, and what expect to do.

也许这个文档是关于 customizing the form template 的对你有用。