django 1.8錯誤：'NoneType'對象不可調用

Question

請看圖中，有一個2字段的表單。用戶輸入信息並提交表單後。該頁面將重定向到另一個html，顯示錶單和過濾的數據庫結果。

我的項目的結構是1模型與2類（inputform;結果），2 html和1 views.py。

現在的問題是「‘NoneType’對象不是可調用的。」所以，我懷疑這是因爲views.py，有什麼不對。你的幫助是非常讚賞。在此先感謝。

網址

from result.views import ResultView,InputFormView 
from django.views.generic import TemplateView,FormView,ListView 

urlpatterns = patterns('',  
    url(r'^result_list/$',ResultView.as_view(),name='result'), 
    url(r'^input/$',InputFormView.as_view(),name='input'), 
) 

views.py

from result.forms import InputForm 
from result.models import Result,Input 
from django.views.generic.list import ListView 
from django.views.generic import FormView 
.... 

@csrf_exempt 

class InputFormView(FormView): 
    template_name = 'inputform.html' 
    form = InputForm 

    def get_success_url(self): /*redirect to result page with submitted form information*/ 
     return ''.join(
      [ 
       reverse('dupont'), 
       '?company=',self.request.POST.get('company'), 
       '?region=',self.request.POST.get('region') 
      ] 
     ) 

class ResultView(ListView): 
    context_object_name = 'result_list' 
    template_name = 'result_list.html' 

    def get_context_data(self, **kwargs): 
     context = super(ResultView, self).get_context_data(**kwargs) 
     return context 

    def get_queryset(self): 
     if self.request.method == 'POST': 
      form = InputForm(self.request.POST) 
      if form.is_valid(): 
       company = form.cleaned_data['company'] 
       region = form.cleaned_data['region'] 

/---Based on form entry, do the filter on the database-----/ 

       queryset=Result.objects.filter(region=region,company=company) 
       sales=Result.objects.filter(queryset).aggregate(Sum('sales')) 
       employee=Result.objects.filter(queryset).aggregate(Sum('employee')) 
       departments=Result.objects.filter(queryset).aggregate(Sum('departments')) 

       form.save() 

       return render(request,'result_list.html',{'company':company},{'region':region},{'employee':employee},{'sales':sales},{'departments':departments}) 

      else: 
       print form.errors 
     else: 
      form=InputForm()     
     return super(ResultView,self).get_queryset() 

回溯：

File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\core\handlers\base.py" in get_response 
132.      response = wrapped_callback(request, *callback_args, **callback_kwargs) 
    File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\base.py" in view 
71.    return self.dispatch(request, *args, **kwargs) 
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\base.py" in dispatch 
89.   return handler(request, *args, **kwargs) 
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\edit.py" in get 
205.   form = self.get_form() 
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\edit.py" in get_form 
74.   return form_class(**self.get_form_kwargs()) 
Exception Type: TypeError at /input/ 
Exception Value: 'NoneType' object is not callable 

result_list.html

<div class="basicinfo">   <!--Entry Form information submitted by user--> 

    <table border="1" cellpadding="1"> 
    <tr> 
     <td align="left">Company</td> 
     <td>{{ company }}</td> 
    </tr> 
    <tr> 
     <td align="left">Region</td> 
     <td>{{ region }}</td> 
    </tr> 
    </table> 
{% endfor %} 
</div>  

<!--Showing the filtered result in database--> 
<td><table border="0" cellspacing="10" cellpadding="10"> 
<tr><b>Sales</b></tr> 
<td bgcolor="#F0F0F0"> {{sales}}</td> 

</tr> 
<tr><b>Employee</b></tr> 
<tr> 
<td bgcolor="#F0F0F0"> {{employee.employee__sum}}</td> 

</tr> 
<tr><b>Departments</b></tr> 
<td bgcolor="#F0F0F0"> {{departments.departments__sum}}</td> 
</td></table> 

input.html

<div class="field"> 
     {{ form.company.errors }} 
     <label for="{{ form.company.id_for_label }}">Company:</label> 
     {{ form.company }} 
</div> 

<div class="field" > 
<label> Select the Region: 
    {{ form.region }} 
     {% for region in form.region.choices %} 
     <option value="region" name= "region" id="id_region">{{region}} </option> 
     {% endfor %} 
</label> 
</div> 

升級views.py根據建議

from result.forms import InputForm 
from django.views.generic import DetailView 
from django.views.generic.edit import FormView,FormMixin 
from django.contrib import messages 
from django.template import RequestContext 
from django.shortcuts import redirect 
from django.db.models import Sum,Avg 
from django.views.generic.detail import MultipleObjectMixin 

class InputFormView(FormMixin,DetailView): 
    template_name = 'inputform.html' 
    form = InputForm 

    def post(self, request, *args, **kwargs): 
     self.object = self.get_object() 
     form=self.get_form() 
     if form.is_valid(): 
      return self.form_valid(form) 
     else: 
      return self.form_invalid(form) 
      print form.errors 

    def get(self, request, *args, **kwargs): 
     view = DupontView.as_view() 
     return view(request, *args, **kwargs) 

    def form_valid(self, form): 
     company = form.cleaned_data['company'] 
     region = form.cleaned_data['region'] 

     queryset=Result.objects.filter(company=company,region=region) 
     sales=Result.objects.queryset.aggregate(Sum('sales')) 
     employee=Result.objects.queryset.aggregate(Sum('employee')) 
     departments=Result.objects.queryset.aggregate(Sum('departments')) 

     return super(ResultView,self).form_valid(form) 

    def get_success_url(self): 
     return reverse('dupont', kwargs={'pk': self.object.pk}) 

class ResultView(MultipleObjectMixin,DetailView): 
    context_object_name = 'result_list' 
    template_name = 'result_list.html' 


    <----how can I get the submitted information and query result here from InputFormView? Is following correct?---> 

    def get(self, request, *args, **kwargs): 
     self.object = self.get_object(queryset=Result.objects.filter(company=company,region=region))    
     return super(Result, self).get(request, *args, **kwargs) 

    def get_context_data(self, **kwargs): 
     context = super(ResultView, self).get_context_data(**kwargs) 
     context['InputFormView']= self.object 
     return context 

    def get_queryset(self): 
     return self.object. ? .all() <---what to put here? are they "sales","departments","employee" from database filtered result together with the form data-"region" and "company"? 

Answer 1

請看看這些文件，也許它們會對你有所幫助。 https://github.com/EchoUA/Tweaks-and-Hacks/tree/master/miaomiao

Answer 2

在views.py中，上下文是一個字典！

return render(request,'result_list.html',{'company':company,'region':region, 'employee':employee, 'sales':sales, 'departments':departments}) 


<div class="basicinfo">   <!--Entry Form information submitted by user--> 

    <table border="1" cellpadding="1"> 
    <tr> 
     <td align="left">Company</td> 
     <td>{{company}}</td> 
    </tr> 
    <tr> 
     <td align="left">Region</td> 
     <td>{{region}}</td> 
    </tr> 
    </table> 

<!--Showing the filtered result in database--> 
<td><table border="0" cellspacing="10" cellpadding="10"> 
<tr><b>Sales</b></tr> 
<td bgcolor="#F0F0F0"> {{sales}}</td> 

</tr> 
<tr><b>Employee</b></tr> 
<tr> 
<td bgcolor="#F0F0F0"> {{employee}}</td> 

</tr> 
<tr><b>Departments</b></tr> 
<td bgcolor="#F0F0F0"> {{departments}}</td> 
</td></table> 

Answer 3

你正在爲一個簡單的表單寫太多的代碼。

創建一個簡單的表單;這僅僅是你的第二個視圖中進行搜索：

class SearchForm(forms.Form): 
    company = forms.CharField() 
    region = forms.CharField() 

創建一個視圖來顯示錶單：

def search_form(request): 
    form = SearchForm(request.GET) 
    if form.is_valid(): 
     company = form.cleaned_data['company'] 
     region = form.cleaned_data['region'] 
     url = '{}?company={}&region={}'.format(reverse('result-list'), company, region) 
     return redirect(url) 
    return render(request, 'form.html', {'form': form}) 

創建一個視圖來顯示結果：

def show_results(request): 
    company = request.GET.get('company') 
    region = request.GET.get('region') 
    if company is None or region is None: 
     return redirect('input') 

    # Your normal logic here 
    queryset=Result.objects.filter(company=company,region=region) 
    sales=Result.objects.aggregate(Sum('sales')) 
    employee=Result.objects.aggregate(Sum('employee')) 
    departments=Result.objects.aggregate(Sum('departments')) 

    return render(request, 'results.html', {'sales': sales, 
              'employee': employee, 
              'departments': departments, 
              'queryset': queryset})    

Answer 4

如果我沒有理解正確地，當您發送GET請求到

127.0.0.1:8000/input/ 

然後你得到錯誤。當您向該網址發送發佈請求時，是否會收到同樣的錯誤？嘗試將input.html更改爲：

<div class="field"> 
    <!-- Check if the errors exist first before calling them. 
     If youre sending a GET request, then form errors will 
     probably not exist. --> 
     {% if form.company.errors %} 
      {{ form.company.errors }} 
      <label for="{{ form.company.id_for_label }}">Company:</label> 
     {% endif %} 
     {{ form.company }} 
</div> 

<div class="field" > 
<label> Select the Region: 
    {{ form.region }} 
     <!-- over here, are you sure form.region.choices exists? Can you 
      post your model/model form so that we can verify that 
      form.region.choices exists? --> 
     {% for region in form.region.choices %} 
     <option value="region" name= "region" id="id_region">{{region}} </option> 
     {% endfor %} 
</label> 
</div> 

讓我知道如果使用此代碼後仍然出現錯誤。在上面的代碼中，我留下了一個提及的註釋來驗證form.region.choices的存在。你可以上傳你的模型和模型表單，以便我們可以驗證form.region.choices是否存在？