class tag(models.Model):
    name = models.CharField(max_length=20, verbose_name='标签')
 
 
class book(models.Model):
    name = models.CharField(max_length=50, verbose_name='书名')
    tags = models.TextField(null=True, verbose_name='标签')

# 标签查询
def get_tag_list():
    return tag.objects.values_list("name", "name")
 
# 表单类定义
class bookForm(forms.ModelForm):
    tags = forms.MultipleChoiceField(label='标签', widget=widgets.CheckboxSelectMultiple)
 
    def __init__(self, *args, **kwargs):
        super(cameraForm, self).__init__(*args, **kwargs)
        
        # 保证每次初始化有最新的标签列表
        self.fields['tags'].choices = get_tag_list()
        
        # 由于会在数据库中存储为列表字符串，需在赋值时转回列表对象，才能在修改表单时识别原值
        self.initial['tags'] = eval(self.initial['tags'])    
 
    class Meta:
        model = book
        exclude = []
 
# book扩展
class bookAdmin(admin.ModelAdmin):
    search_fields = 'name', 'tags')
    list_display = ( 'name', 'tags')
    form = bookForm
 
# 注册到admin中
admin.site.register(book, bookAdmin)