Question

选中删除复选框后，提交表单时不会删除LayerMapOptions实例。否则，表单适用于所有其他字段。通过模型的形式有什么特别的事情要做吗？

模型：

class EzMap(models.Model):
    map_name = models.SlugField(max_length=50)
    layers = models.ManyToManyField(Shapefile, through='LayerMapOptions', verbose_name='Layers to display', null=True, blank=True)

class Shapefile(models.Model):
    filename = models.CharField(max_length=255)

class LayerMapOptions(models.Model):
    layer = models.ForeignKey(Shapefile)
    ezmap = models.ForeignKey(EzMap)
    position = models.IntegerField(max_length=100)
    visible = models.BooleanField()

视图：

def setMapOptions(request, map_name):
    map_selected = EzMap.objects.get(map_name=map_name, created_by=request.user)
    layers_ordered = LayerMapOptions.objects.filter(ezmap=map_selected).order_by('position')
    layerForm = modelformset_factory(LayerMapOptions, form=LayerMapOptionsForm, extra=0, can_delete=True)
        if request.POST:
            formset = layerForm(request.POST, queryset=layers_ordered)
            pk_list = request.POST.get("layersOrder")

            if formset.is_valid():
                for form in formset:
                    instance = form.instance
                    instance.position = pk_list.index(instance.pk)
                    instance.save()

            save_link = u"/ezmapping/map/%s" % (map_name)
            return HttpResponseRedirect(save_link)
        else:
            formset = layerForm(queryset=layers_ordered)
     return render_to_response("ezmapping/manage_map_Options.html", {'formset': formset}, context_instance=RequestContext(request))

形式：

class LayerMapOptionsForm(ModelForm):
    link = forms.CharField(label='link', required=False)

    def __init__(self, *args, **kwargs):
        super(LayerMapOptionsForm, self).__init__(*args, **kwargs)
        self.fields['link'].widget = ModelLinkWidget(self.instance.layer)

    class Meta:
        model = LayerMapOptions
        fields =  ['link', 'visible']

Answer 1

您正在保存单个实例。相反，您需要在formset上调用save（）来触发自动删除所选项。更仔细地阅读文档。

https://docs.djangoproject.com/en/1.5/topics/forms/formsets/#can-delete

如果您使用的是ModelFormSet，则在调用formset.save（）时将删除已删除表单的模型实例。另一方面，如果您使用的是普通的FormSet，则可以在formset的save（）方法中处理formset.deleted_forms，因为没有关于删除表单意味着什么的一般概念。

Django - ModelForm can_delete = True不使用M2M（直通）模型

1 个答案: