覆盖Django ModelForm中的ChoiceField小部件，无需重新指定选项 [英] Override ChoiceField widget in Django ModelForm without re-specifying choices

问题描述

我正在尝试覆盖Django ChoiceField 的默认窗口小部件，同时保留模型中生成的选项。以下是我的模型的相关部分：

  class UserGroup（models.Model）：
 icon = models.CharField （max_length = 100，choices =< function call>）
  

我的形式：

  class UserGroupForm（forms.ModelForm）：
 icon = models.ChoiceField（widget = IconPicker）
 
 class Meta：
 model = UserGroup 
 fields = ['icon'，] 
  

覆盖 ChoiceField 的小部件就像这样消除了 form.fields ['icon']。选项属性继承自模型，并将其设置为 [] ，因为Django。如果我从表单中删除图标字段定义，则会保留选项 - 但是当然，该窗口小部件默认为选择。

（生成模型字段选项的函数不可用表单代码访问。）

我到目前为止最好的是将图标表单字段定义更改为

  icon = ChoiceField（choices = UserGroup._meta.get_field_by_name（'icon'）[0] .choices，
 widget = IconPicker）
  pre> 
 
 
但这是笨重的，我宁愿自动传递选项，就像内向 ChoiceField 行为一样。 （我尝试将 ChoiceField 子类化为 IconChoiceField 这是相同的，但默认的小部件 IconPicker 但Django将它转换回一个 TypedChoiceField 与默认的选择小部件因为此问题。）
 
 
 
有没有办法覆盖 ChoiceField 的小部件属性，同时保留继承选择的行为从模型？ 
解决方案
我认为你失去在你的模型中指定的选择的原因，即将它设置为 [] 不是因为Django，而是因为您使用行 icon = models.ChoiceField（widget = IconPicker）覆盖图标字段请注意，如果您使用的是模型窗体，则不必在init处覆盖窗口小部件，而应该在窗体中指定该窗口小部件。元组字典中的Meta类。 
  class UserGroupForm（forms.ModelForm）：
 
 class Meta：
 model = UserGroup 
 fields = ['icon'，] 
 widgets = {
'icon'：IconPicker 
} 
  
为了覆盖选项，您可以简单地执行 self.fields ['icon']。choices = UserGroupForm.ICON_CHOICES ，但在这种情况下，我不认为你需要重写选择。
 
I am trying to override the default widget for a Django ChoiceField while preserving the choices generated in the model.  Here is the relevant part of my model:
class UserGroup(models.Model):
    icon = models.CharField(max_length=100, choices=<function call>)
And of my form:
class UserGroupForm(forms.ModelForm):
    icon = models.ChoiceField(widget=IconPicker)

    class Meta:
        model = UserGroup
        fields = [ 'icon', ]
Overriding the ChoiceField's widget like this clobbers the form.fields['icon'].choices attribute normally inherited from the model and sets it to [] because Django.  If I remove the icon field definition from the form, the choices are preserved - but of course the widget defaults to a Select.  

(The function which generates the choices for the model field is not accessible from the form code unfortunately.)

The best I have come up with so far for is to change the icon form field definition to
icon = ChoiceField(choices=UserGroup._meta.get_field_by_name('icon')[0].choices, 
                   widget=IconPicker)
but this is clunky and I would rather have the choices automatically passed on as in the introspected ChoiceField behavior.  (I tried subclassing ChoiceField to IconChoiceField which was identical but for a default widget of IconPicker but Django converts it back to a TypedChoiceField with the default Select widget because of this issue.)

Is there a way to override the ChoiceField's widget attribute while preserving the behavior of inheriting choices from the model?  
解决方案
I think the reason you are losing the choices you specified in your model i.e. "sets it to []" is not "because Django", but because you override the icon field with the line icon = models.ChoiceField(widget=IconPicker)

Please note that if you are using a modelform then it is not necessary to override the widget at init, instead the widget should be specified in the Meta class in the widgets dictionary. 
class UserGroupForm(forms.ModelForm):

    class Meta:
        model = UserGroup
        fields = [ 'icon', ]
        widgets = {
            'icon': IconPicker
        }
As for overriding the choices you can simply do self.fields['icon'].choices = UserGroupForm.ICON_CHOICES, but I don't think you need to override choices in this instance.

                        
这篇关于覆盖Django ModelForm中的ChoiceField小部件，无需重新指定选项的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！