Django根据另一个字段表单更新表单

Question

我有以下 Django 表单:

label = forms.CharField(label="Label",
                        min_length=2,
                        max_length=100,
                        required=True,
                        widget=forms.TextInput(attrs={'class': 'form-control input-sm'}))

hour = forms.ChoiceField(label="Hour",
                         choices=choice_hour,
                         required=True,
                         widget=forms.Select(attrs={'class': 'form-control input-sm'}))

minute = forms.ChoiceField(label="Minute",
                           choices=choice_minute,
                           required=True,
                           widget=forms.Select(attrs={'class': 'form-control input-sm'}))

period = forms.MultipleChoiceField(label="Day of week",
                                   choices=choice_period,
                                   required=True,
                                   error_messages={'required': 'At least you must select one day'},
                                widget=forms.CheckboxSelectMultiple(renderer=HorizontalCheckboxRenderer))


snooze = forms.ChoiceField(label="Auto stop",
                           choices=choice_snooze,
                           required=True,
                           widget=forms.Select(attrs={'class': 'form-control input-sm'}))


mode = forms.ChoiceField(label="Mode",
                          choices=choice_mode,
                          required=True,
                          widget=forms.Select(attrs={'class': 'form-control input-sm'}))

if mode == 'music':
        webradio = forms.ModelChoiceField(queryset=Webradio.objects.all(),
                                      widget=forms.Select(attrs={'class': 'form-control input-sm'}), required=False)
    else:
        webradio = forms.ModelChoiceField(queryset=Webradio.objects.all(),
                                  widget=forms.Select(attrs={'class': 'form-control input-sm'}), required=True)

    class Meta:
        model = Alarmclock
        fields = ['label', 'hour', 'minute', 'period', 'snooze', 'mode', 'webradio']

“模式”字段形式允许知道用户是想要“ radio ”还是“音乐”。

当Mode为'music'时，webradio字段可以为空。但是当 Mode 为 'radio' 时，必须设置 webradio 字段。

如何根据模式更新 webradio 字段表单？

我尝试使用 IF 条件，但我认为未找到模式变量，webradio 字段一直是必需的。

谢谢。

Answer 1

将webradio字段定义为不需要，然后在clean方法中进行验证(clean的目的是对相互依赖的字段进行验证)。

class Form(forms.ModelForm):

    # other fields ...

    mode = forms.ChoiceField(
        label="Mode", choices=choice_mode, required=True,
        widget=forms.Select(attrs={'class': 'form-control input-sm'})
    )
    webradio = forms.ModelChoiceField(
        queryset=Webradio.objects.all(),
        widget=forms.Select(attrs={'class': 'form-control input-sm'}),
        required=False
    )

    class Meta:
        model = Alarmclock
        fields = ['label', 'hour', 'minute', 'period', 'snooze', 'mode', 'webradio']

    def clean(self):
        mode = self.cleaned_data.get('mode')
        if mode == 'music':
            webradio = self.cleaned_data.get('webradio')
            if not webradio:
                raise forms.ValidationError({'webradio': 'Webradio field is required.'})

查看 the docs了解更多详情。

请注意，此方法在 Django 1.7 中已更改:

In previous versions of Django, form.clean() was required to return a dictionary of cleaned_data. This method may still return a dictionary of data to be used, but it’s no longer required.