我有一个表格,让我先选择产品类型,然后选择产品。因为我有1000+的产品我用下面的过滤产品列表来提高性能。
我在我的views.py以下inlineform
OrderLineFormSet = inlineformset_factory(OrderHeader, OrderLine, OrderLineForm, extra = 1)
在我forms.py我检查,如果已经有选择的产物。如果选择一个产品,我只显示与同类型的产品,以提高负载性能的产品。如果产品是空的,将加载所有的产品选项,以便它可以让我保存表单选择之后。
class OrderLineForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(OrderLineForm, self).__init__(*args, **kwargs)
self.helper = FormHelper(self)
self.helper.form_show_errors = True
self.helper.error_text_inline = False
if self.instance.product is not None:
self.fields['product'] = forms.ModelChoiceField(queryset=Product.objects.filter(product_type_id=self.instance.product_type_id), required=False)
这将导致以下形式
然而,当我改变现有的窗体上的产品类型(再使用jQuery来更新产品下拉列表)我得到一个错误的节省。我知道这是因为选择不是在下拉列表中选择一个选项。
我的问题:我怎么能这样可以节省我选择的选项,无论原始选项禁用此错误。
下面你会发现我的views.py这种形式
def orderline_formset(request, id=None):
OrderLineFormSet = inlineformset_factory(OrderHeader, OrderLine, OrderLineForm, extra = 1)
orderheader = None
orderid = None
orderheaderid = 0
if id:
orderid = OrderHeader.objects.get(pk=id)
if request.POST:
if orderid:
form = OrderHeaderForm(request.POST, instance=orderid)
formset = OrderLineFormSet(request.POST,instance=orderid)
else:
form = OrderHeaderForm(request.POST)
formset = OrderLineFormSet(request.POST)
if form.is_valid() and formset.is_valid():
if orderid:
form.save() # update object
else:
orderid = form.save() # create object
formset.instance = orderid
formset.save()
messages.success(request, 'Order saved succesfully!')
return HttpResponseRedirect('/orderline_formset/' + str(orderid.pk))
else: # form invalid
messages.error(request, 'Order save error, please check mandatory fields')
else: # request.GET
if orderid:
invoiceheader = ""
if orderid.orderheader_invoice:
invoiceheader = " -- Invoice " + str(orderid.orderheader_invoice)
orderheader = "Order " + str(orderid.pk) + invoiceheader
orderheaderid = orderid.pk
form = OrderHeaderForm(instance=orderid)
formset = OrderLineFormSet(instance=orderid)
else:
orderheader = "New Order"
orderheaderid = 0
form = OrderHeaderForm(instance=OrderHeader())
formset = OrderLineFormSet(instance=OrderHeader())
return render_to_response("order-add.html", {'form' : form,'formset': formset,
'orderheader': orderheader,
'orderheaderid': orderheaderid},
context_instance=RequestContext(request))
覆盖ModelChoiceField
,例如:
class MyModelChoiceField(ModelChoiceField):
def to_python(self, value):
try:
value = super(MyModelChoiceField, self).to_python(value)
except self.queryset.model.DoesNotExist:
key = self.to_field_name or 'pk'
value = Product.objects.filter(**{key: value})
if not value.exists():
raise ValidationError(self.error_messages['invalid_choice'], code='invalid_choice')
else:
value= value.first()
return value
而在你的表单中使用它。
self.fields['product'] = MyModelChoiceField(queryset=Product.objects.filter(product_type_id=self.instance.product_type_id), required=False)
你必须改变
self.fields['product'] = forms.ModelChoiceField(queryset=Product.objects.filter(product_type_id=self.instance.product_type_id), required=False)
至
self.fields['product'] = forms.ModelChoiceField(queryset=Product.objects.all(), required=False)
不过你已经知道这一点,不希望它因为性能原因让你其他的解决办法是将其更改为
self.fields['product'] = ModelChoiceField(queryset=Product.objects.all(), widget=forms.HiddenInput, required=False)
那么你的模板里面你手动构建您的<select>
标签和使用JS手柄onchange
事件,并使其更新产品领域
class OrderLineForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(OrderLineForm, self).__init__(*args, **kwargs)
self.helper = FormHelper(self)
self.helper.form_show_errors = True
self.helper.error_text_inline = False
self.fields['product'] = forms.ModelChoiceField(
queryset=Product.objects.all())
self.fields['product'].required = False
在此之后,你可以过滤器中选择使用jQuery的过滤器。
更新@ruddra的Django的1.11答案:
class DynamicModelChoiceField(ModelChoiceField):
def to_python(self, value):
try:
value = super().to_python(value)
except ValidationError:
key = self.to_field_name or 'pk'
value = self.queryset.model.objects.filter(**{key: value})
if not value.exists():
raise
value = value.first()
return value