from __future__ import unicode_literals
from django.db import models
from django.db.models import ForeignKey, CASCADE
[docs]class TopLevel(models.Model):
name = models.CharField(max_length=200)
[docs]class LevelOne(models.Model):
name = models.CharField(max_length=200)
parent_level = ForeignKey(TopLevel, related_name='children', on_delete=CASCADE)
position = models.PositiveIntegerField()
class Meta:
ordering = ('position', )
[docs]class LevelTwo(models.Model):
name = models.CharField(max_length=200, blank=True)
parent_level = ForeignKey(LevelOne, related_name='children', on_delete=CASCADE)
position = models.PositiveIntegerField(blank=True, null=True)
class Meta:
ordering = ('position', )
[docs]class LevelThree(models.Model):
name = models.CharField(max_length=200)
parent_level = ForeignKey(LevelTwo, related_name='children', on_delete=CASCADE)
position = models.PositiveIntegerField()
class Meta:
ordering = ('position', )