django m2m_changed 不工作

Question

我有简单的代码，错误不起作用！在向未称为 tag_update_count_use!

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模型.py

class Tag(models.Model):
    count_use = models.PositiveIntegerField(_('count use'), default=0)

    def update_count_use(self, delta):
        self.count_use += delta
        self.save(update_fields=['count_use'])

class Content(models.Model):
    tags = models.ManyToManyField('Tag', blank=True, verbose_name=_('tags'))

signals.py

from django.db.models.signals import m2m_changed
from django.dispatch import receiver

@receiver(m2m_changed, sender=Content.tags)
def tag_update_count_use(sender, **kwargs):
    print(kwargs)
    return kwargs

__init__.py

default_app_config = 'content.apps.ContentConfig'

apps.py

class ContentConfig(AppConfig):
    name = 'content'
    verbose_name = _('content')

    def ready(self):
        import content.signals

根据 https://docs.djangoproject.com/en/dev/ref/signals/#m2m-changed 我将代码更改为：

@receiver(m2m_changed, sender=Content.tags.though)

但我收到此错误：

AttributeError: 'ManyToManyDescriptor' object has no attribute 'though'

Answer 1

您错过了 through 中的 r。尝试：

@receiver(m2m_changed, sender=Content.tags.through)

django m2m_changed 不工作

django m2m_changed not working

python

django

signals

models