__init__中的Queryset形式Django

Question

class PaymentSelectForm(forms.Form):   
    date_from = forms.DateField()
    date_to = forms.DateField()
    website = ModelChoiceField() 
    paymentmethod = forms.ChoiceField(choices=PAYCODE_CHOICES)

    def __init__(self, *args, **kwargs):
        super(PaymentSelectForm, self).__init__(*args, **kwargs)
        applyClassConfig2FormControl(self) 
        self.fields['website'].queryset=Website.objects.all()

我有错误：TypeError： __init__()缺少1个必需的位置参数：'queryset'。 如何在__init__表单中使用Queryset ？

Answer 1

除非您当前隐藏了某些信息，否则最好在ModelChoiceField的声明中声明查询集 ：

class PaymentSelectForm(forms.Form):

    date_from = forms.DateField()
    date_to = forms.DateField()
    website = ModelChoiceField(queryset=Website.objects.all()) 
    paymentmethod = forms.ChoiceField(choices=PAYCODE_CHOICES)

    def __init__(self, *args, **kwargs):
        super(PaymentSelectForm, self).__init__(*args, **kwargs)
        applyClassConfig2FormControl(self)

如果查询集是动态的 （这里不是这种情况），您可以最初将其设置为None ，然后在__init__函数中覆盖它：

class PaymentSelectForm(forms.Form):

    date_from = forms.DateField()
    date_to = forms.DateField()
    website = ModelChoiceField(queryset=None) 
    paymentmethod = forms.ChoiceField(choices=PAYCODE_CHOICES)

    def __init__(self, *args, **kwargs):
        super(PaymentSelectForm, self).__init__(*args, **kwargs)
        applyClassConfig2FormControl(self)
        self.fields['website'].queryset=Website.objects.all()

但是，这在通常情况下如果例如queryset取决于传递给表单参数，或者依赖于其他表（它不能优雅地写入到SQL查询）。

Answer 2

使用widget.choices

def __init__(self, *args, **kwargs):
        super(PaymentSelectForm, self).__init__(*args, **kwargs)
        applyClassConfig2FormControl(self) 
        self.fields['website'].widget.choices=(
            (choice.pk, choice) for choice in Website.objects.all()
        )