django - Django 中的动态 MultiValueField

Question

我正在尝试基于动态创建其字段的 MultiValueField 创建自定义小部件。类似的东西:

class MyField(MultiValueField):
    def __init__(self, my_param, *args, **kwargs):
        fields = []
        for field in my_param.all():
            fields.append(forms.ChoiceField(
              widget=forms.Select(attrs={'class':'some_class'})))

    super(MyField, self).__init__(
        self, fields=tuple(fields), *args, **kwargs)

以及使用该字段的表单，如下所示:

class MyForm(forms.Form):
    multi_field = MyField()
    def __init__(self, *args, **kwargs):
        super(MyForm, self).__init__(*args, **kwargs)
        self.fields['multi_field'].my_param = self.initial['car_types'].another

我现在不知何故被困住了。如何将参数(例如 my_param)传递给 MyField 的 初始化 () 方法，当参数仅从 MyForm 的构造函数中知道时(例如 self.initial['car_types'].another)？

Answer 1

您需要在 __init__ 中实例化您的字段:

class MyForm(forms.Form):
    def __init__(self, *args, **kwargs):
        super(MyForm, self).__init__(*args, **kwargs)
        self.fields['multi_field'] = MyField(self.initial['car_types'].another)