我在限制formset中的可选选项时遇到了问题.我有以下模型：员工,部门,项目,项目类型,成员资格和角色.员工可以在表单集中添加/删除他们为给定部门项目播放的角色,表单应该将可选项目限制为仅属于员工所属部门的项目.
楷模：
class Department(models.Model):
name = models.CharField(max_length=20)
def __unicode__(self):
return self.name
class Employee(models.Model):
fname = models.CharField(max_length=15)
department = models.ForeignKey(Department)
def __unicode__(self):
return self.fname
class Projecttype(models.Model):
name = models.CharField(max_length=20)
def __unicode__(self):
return self.name
class Project(models.Model):
projecttype = models.ForeignKey(Projecttype)
department = models.ForeignKey(Department)
members = models.ManyToManyField(Employee,through='Membership')
def __unicode__(self):
return "%s > %s" % (self.department,self.projecttype)
class Role(models.Model):
name = models.CharField(max_length=20)
def __unicode__(self):
return self.name
class Membership(models.Model):
project = models.ForeignKey(Project,null=True)
department = models.ForeignKey(Department)
employee = models.ForeignKey(Employee)
role = models.ManyToManyField(Role,blank=True,null=True)
class Meta:
unique_together = (("project","employee",),)
视图：
def employee_edit(request,employee_id):
i = get_object_or_404(Employee,pk=employee_id)
MembershipFormSet = modelformset_factory(Membership,exclude=('department','employee'),)
f = MembershipFormSet(queryset=Membership.objects.filter(employee=i),)
return render_to_response('gcs/edit.html',{'item': i,'formset': f,},context_instance=RequestContext(request))
现在,欧盟可以为任何部门项目选择一个角色.它的行为如下：
项目选择：
Projects.objects.all()
我想用这样的方式限制项目：LIMIT PROJECT CHOCIES TO：
Projects.objects.filter(department=i.department)
解决方法
这个
Stack Overflow question非常相似.我喜欢Matthew的答案,你可以在一个通过闭包访问员工的函数中动态构建表单.在你的情况下,你想要的东西：
from django.http import HttpResponseRedirect
def make_membership_form(employee):
"""
Returns a Membership form for the given employee,restricting the Project choices to those in the
employee's department.
"""
class MembershipForm(forms.ModelForm):
project = forms.ModelChoiceField(queryset=Projects.objects.filter(department=employee.department))
class Meta:
model = Membership
excludes = ('department','employee',)
return MembershipForm
def employee_edit(request,employee_id):
employee = get_object_or_404(Employee,pk=employee_id)
# generate a membership form for the given employee
MembershipForm = make_membership_form(employee)
MembershipFormSet = modelformset_factory(Membership,form=MembershipForm)
if request.method == "POST":
formset = MembershipFormSet(request.POST,queryset=Membership.objects.filter(employee=employee))
if formset.is_valid():
instances = formset.save(commit=False)
for member in instances:
member.employee = employee
member.department = employee.department
member.save()
formset.save_m2m()
# redirect after successful update
return HttpResponseRedirect("")
else:
formset = MembershipFormSet(queryset=Membership.objects.filter(employee=employee),)
return render_to_response('testdb/edit.html',{'item': employee,'formset': formset,context_instance=RequestContext(request))