Django 限制基于其他字段的外部字段的选择
型号Django 限制基于其他字段的外部字段的选择,django,Django,型号 from django.db import models from test.test_imageop import MAX_LEN class Student(models.Model): first_name = models.CharField(max_length=128) last_name = models.CharField(max_length=128) mail_adress = models.EmailField(max_length=128)
from django.db import models
from test.test_imageop import MAX_LEN
class Student(models.Model):
first_name = models.CharField(max_length=128)
last_name = models.CharField(max_length=128)
mail_adress = models.EmailField(max_length=128)
def __unicode__(self):
return self.first_name+" "+self.last_name
class Course(models.Model):
name = models.CharField(max_length=128)
description = models.CharField(max_length=256)
students=models.ManyToManyField(Student)
def __unicode__(self):
return self.name
# Create your models here.
class Task(models.Model):
course= models.ManyToManyField(Course)
name = models.CharField(max_length=128)
description = models.CharField(max_length=256)
students=models.ManyToManyField(Student,limit_choices_to={'course' : Course},blank=True)
def __unicode__(self):
return self.name
管理
from django.contrib import admin
from .models import Student
from .models import Course
from .models import Task
class StudentAdmin(admin.ModelAdmin):
pass
admin.site.register(Student,StudentAdmin)
class CourseAdmin(admin.ModelAdmin):
pass
admin.site.register(Course,CourseAdmin)
class TaskAdmin(admin.ModelAdmin):
pass
admin.site.register(Task,TaskAdmin)
# Register your models here.
我的想法是,当我创建一个任务并选择一门课程时,只有分配给这门课程的学生才能被选择,并且我为其他成员尝试了很多答案,但在这种情况下不起作用,如果你有想法,请帮助我
您需要在表单中筛选学生。在管理方面,此黑客可能会有所帮助:
class TaskAdmin(admin.ModelAdmin):
def get_form(self, request, obj=None, **kwargs):
request._obj_ = obj
return super(TaskAdmin, self).get_form(request, obj, **kwargs)
def formfield_for_manytomany(self, db_field, request=None, **kwargs):
field = super(TaskAdmin, self).formfield_for_foreignkey(db_field, request, **kwargs)
if db_field.name == 'students':
if request._obj_ is not None:
field.queryset = field.queryset.filter(id__in=request._obj_.course.students.all())
else:
field.queryset = field.queryset.none()
return field
对于您的ModelForm
s:
class TaskForm(forms.ModelForm):
def __init__(self, course, *args, **kwargs):
super(TaskForm, self).__init__(*args, **kwargs)
self.fields['students'].queryset = course.students
class Meta:
model = Task
fields = '__all__'
然后,在实例化表单时,您必须通过课程:
form = TaskForm(course, request.POST)
您需要在admin.py中使用
formfield\u for\u manytomy
。文档在这里