Admin和Meta没有看到父抽象类的字段

时间:2017-04-20 06:11:41

标签: django python-3.x inheritance django-models

我使用Django 1.10。我有以下模型结构:

class GenericPage(models.Model):
    """Abstract page, other pages inherit from it."""
    book = models.ForeignKey('Book', on_delete=models.CASCADE)

    class Meta:
        abstract = True

class GenericColorPage(models.Model):
    """Abstract page that is sketchable and colorable, other pages inherit from it."""
    sketched = models.BooleanField(default=False)
    colored = models.BooleanField(default=False)

    class Meta:
        abstract = True

class GenericBookPage(GenericColorPage):
    """A normal book page, with a number. Needs to be storyboarded and edited."""

    ###
    #various additional fields
    ###

    class Meta:
        # unique_together = (('page_number', 'book'),) # impedes movement of pages
        ordering = ('-book', '-page_number',)
        abstract = True

    objects = BookPageManager()  # the manager for book pages

class BookPage(GenericBookPage):
    """Just a regular book page with text (that needs to be proofread)"""
    proofread = models.BooleanField(default=False)

此外,摘自管理员:

class BookPageAdmin(admin.ModelAdmin):
    # fields NOT to show in Edit Page.
    list_display = ('__str__', 'page_name', 'sketched', 'colored', 'edited', 'proofread',)
    list_filter = ('book',)
    readonly_fields = ('page_number',)  # valid page number is assigned via overridden save() in model
    actions = ['delete_selected',]

我尝试./manage.py makemigrations但是如果抛出以下错误:

<class 'progress.admin.BookPageAdmin'>: (admin.E116) The value of 'list_filter[0]' refers to 'book', which does not refer to a Field.
progress.BookPage: (models.E015) 'ordering' refers to the non-existent field 'book'.

过去,当我没有使用摘要并将所有内容都放入BookPage模型时,一切正常。但似乎Meta和Admin没有看到父类中的字段。我错过了什么吗?有没有办法让他们从抽象的父母那里读取字段?

1 个答案:

答案 0 :(得分:2)

  

过去,当我没有使用摘要并将所有内容都放入BookPage模型时,一切都运行良好

当然它运行正常,因为你把所有内容放在BookPage里面而不是abstract class,这意味着将创建表格(以及字段)。

  

但似乎Meta和Admin没有看到父类中的字段。我错过了什么吗?

您错过了这样一个事实:您的模型都没有从GenericPage抽象模型继承。因此,永远不会创建book字段。

  

有没有办法让他们从抽象父母那里读取字段?

您必须创建/修改从抽象模型继承的模型。也许,这样做:

class GenericBookPage(GenericColorPage, GenericPage):

允许您继承GenericColorPageGenericPage字段。当我说继承时,我的意思是当migrate命令运行以实际创建数据库表和相关列(模型字段)时。