class PurchaseOrder(models.Model):
product = models.ManyToManyField('Product')
vendor = models.ForeignKey('VendorProfile')
dollar_amount = models.FloatField(verbose_name='Price')
class Product(models.Model):
products = models.CharField(max_length=256)
def __unicode__(self):
return self.products
I have that code. Unfortunately, the error comes in admin.py with the ManyToManyField
class PurchaseOrderAdmin(admin.ModelAdmin):
fields = ['product', 'dollar_amount']
list_display = ('product', 'vendor')
The error says:
'PurchaseOrderAdmin.list_display[0]', 'product' is a ManyToManyField which is not supported.
However, it compiles when I take 'product'
out of list_display
. So how can I display 'product'
in list_display
without giving it errors?
edit: Maybe a better question would be how do you display a ManyToManyField
in list_display
?
You may not be able to do it directly. From the documentation of list_display
ManyToManyField fields aren’t supported, because that would entail executing a separate SQL statement for each row in the table. If you want to do this nonetheless, give your model a custom method, and add that method’s name to list_display. (See below for more on custom methods in list_display.)
You can do something like this:
class PurchaseOrderAdmin(admin.ModelAdmin):
fields = ['product', 'dollar_amount']
list_display = ('get_products', 'vendor')
def get_products(self, obj):
return "\n".join([p.products for p in obj.product.all()])
OR define a model method, and use that
class PurchaseOrder(models.Model):
product = models.ManyToManyField('Product')
vendor = models.ForeignKey('VendorProfile')
dollar_amount = models.FloatField(verbose_name='Price')
def get_products(self):
return "\n".join([p.products for p in self.product.all()])
and in the admin list_display
list_display = ('get_products', 'vendor')