我的
models.py
:
class Subject(models.Model):
name = models.CharField(max_length=200)
class Person(models.Model):
subject = models.ForeignKey(Subject, on_delete=models.CASCADE, blank=True, null=True)
school = models.ForeignKey(School, on_delete=models.CASCADE, blank=True, null=True)
class PersonRole(models.Model):
project = models.ForeignKey('Project', on_delete=models.CASCADE)
person = models.ForeignKey(Person, on_delete=models.CASCADE)
class Project(models.Model):
title = models.CharField(max_length=200)
person = models.ManyToManyField(Person, through=PersonRole)
现在,在我的管理后端中,我想使用
list_filter
添加一个不错的过滤。此过滤器应该可以按学校过滤某人所属的项目。换句话说,如果约翰(属于“1 号”学校)附属于 1 号项目。 3,我希望后端的项目表只显示项目号。 3.
我想我应该定制一个simplelistfilter。不过,首先,我对如何获取项目附属人员的学校列表有点困惑。
到目前为止我的尝试是:
class PersonRole(models.Model):
[...]
def get_school(self):
return self.person.school
class Project(models.Model):
@admin.display(description='PI School')
def get_PI_school(self):
return [p for p in self.person.get_school()]
admin.py
:
class ProjectAdmin(admin.ModelAdmin):
list_display = ("get_PI_school",) #This is just to see if the field is populated
有了这个,我得到了
'ManyRelatedManager' object has no attribute 'get_school'
。
您在
.get_school()
对象上使用 PersonRole
:
class Project(models.Model):
@admin.display(description='PI School')
def get_PI_school(self):
return [p.get_school() for p in self.personrole_set.all()]
我们可以通过在同一查询中获取相关的
Person
和 School
来提高效率:
class Project(models.Model):
@admin.display(description='PI School')
def get_PI_school(self):
return [
p.get_school()
for p in self.personrole_set.select_related('person__school')
]
您可以使用以下方式筛选 PI 角色:
class Project(models.Model):
@admin.display(description='PI School')
def get_PI_school(self):
return [
p.get_school()
for p in self.personrole_set.filter(
title__contains="Principal investigator"
)
]
当然,您的
PersonRole
模型仍然具有 title
字段。
在尝试了不同的选项后,我设法使用
SimpleListFilter
来做到这一点,而且比我想象的要容易!我什至不需要在 properties
中定义 models.py
等。这是代码,进入 admin.py
:
class PISchoolFilter(admin.SimpleListFilter):
title = 'PI School'
parameter_name = 'school'
def lookups(self, request, model_admin):
return (
('Arts & Humanities Admin',('Arts & Humanities Admin')),
[...]
)
def queryset(self, request, queryset):
if self.value() == 'Arts & Humanities Admin':
return queryset.filter(
person__personrole__person_role__contains="Principal investigator",
person__personrole__person__school=5
).distinct()
[...]