在Django模型表单中使用Model属性

I am attempting to use model properties like fields within a model form, but so far haven't had any luck. The result is that the form renders only the model fields, and not the property I defined. Any idea how to get the form to recognize the property added to the model? I expect to see the latitude property added as just another field in the form.

我试图使用模型属性,如模型形式中的字段,但到目前为止还没有任何运气。结果是表单只呈现模型字段,而不是我定义的属性。知道如何让表单识别添加到模型中的属性吗?我希望将latitude属性添加为表单中的另一个字段。

Models.py:

class Plot(models.Model):
        plot_id = models.AutoField(primary_key=True)
        plot_number = models.IntegerField(validators=[MinValueValidator(1)], null=False, unique=True)
        geometry = models.PointField(srid=2163, null=True, blank=True) 
        objects = models.GeoManager()

        @property
        def latitude(self):
            self.geometry.transform(4326)
            return self.geometry.y

        @latitude.setter
        def latitude(self, latitude):
            self.geometry.y = latitude

Forms.py:

class InventoryPlotForm(ModelForm):
    class Meta:
        model = ForestInventoryPlot
        exclude = {"geometry"}

2 个解决方案

#1

Your property is not a Field instance, and as such a ModelForm cannot automatically generate a form field for it. You will need to explicitly define a latitude field on the InventoryPlotForm and manage its retrieval and update in the form's __init__ and save methods. Alternatively, you can implement your own Widget class and tell your InventoryPlotForm to use it for the geometry field:

您的属性不是Field实例,因此ModelForm无法自动为其生成表单字段。您需要在InventoryPlotForm上明确定义纬度字段,并在表单的__init__和save方法中管理其检索和更新。或者,您可以实现自己的Widget类,并告诉InventoryPlotForm将其用于几何字段:

class InventoryPlotForm(ModelForm):
    class Meta(object):
        widgets = {
            'geometry': MyGeometryWidget,
        }
        ...
    ...

#2

Only Django Fields are automatically generated by ModelForm.

只有Django字段由ModelForm自动生成。

You need to define your field in the ModelForm

您需要在ModelForm中定义您的字段

Probably make geometry field hidden

可能会隐藏几何场

Write custom ModelForm Save method and separately save model fields and model properties.

编写自定义ModelForm Save方法并单独保存模型字段和模型属性。

Modify your view to set the initial for the ModelForm

修改视图以设置ModelForm的初始值

For example something like this:

例如这样的事情:

class InventoryPlotForm(ModelForm):
    latitude = forms.CharField(max_length=52)           # Something like this

    def save(self, commit=True):
        model_instance = super(InventoryPlotForm, self).save(commit=False)
        result = super(InventoryPlotForm, self).save(commit=True)
        model_instance.latitude = self.cleaned_data['latitude']
        model_instance.save()
        return result

    class Meta:
        model = ForestInventoryPlot
        widgets = {'geometry': HiddenInput()}

in your view

在你看来

...
form = InventoryPlotForm(instance=forestinventoryplot,
                         initial={"latitude":forestinventoryplot.latitude})
...

#1

class InventoryPlotForm(ModelForm):
    class Meta(object):
        widgets = {
            'geometry': MyGeometryWidget,
        }
        ...
    ...

#2