Django模型中的动态选择字段 [英] Dynamic choices field in Django Models

问题描述

我的models.py：

My models.py:

SHOP1_CHOICES = (
    ('Food Court', 'Food Court'),
    ('KFC', 'KFC'),

)

SHOP2_CHOICES = (
    ('Sports Arena', 'Sports Arena'),
    ('Disco D', 'Disco D'),

)

SHOP3_CHOICES = (
    ('Bowling Arena', 'Bowling Arena'),
    ('Cinemax', 'Cinemax'),

)

class Feed(models.Model):
  gender = models.CharField(max_length=5, choices=GENDER_CHOICES, default='girl')
  name =models.CharField(max_length=25)
  shop=models.CharField(max_length=20)
  location=models.CharField(max_length=25, choices=SHOP1_CHOICES)

这里如果 Feed .shop =='shop1'我想在 Feed.location 上加载 SHOP1_CHOICES 。目前，无论什么商店，它只显示 SHOP1_CHOICES （没有惊喜）。我如何实现？我被卡住了，请帮忙。

Here if Feed.shop == 'shop1' I want to load SHOP1_CHOICES on Feed.location. Currently irrespective of what shop, it just displays the SHOP1_CHOICES (no surprise).How can I implement it? I am stuck, please help.

推荐答案

这是我的方法：

我使用懒惰来进行懒惰加载：

I use lazy for lazy load:

from django.utils.functional import lazy

这里有一个助手来选择选项：

Here, a helper to chose options:

def help_SHOP_CHOICES():
    SHOP1_CHOICES = [
        ('Food Court', 'Food Court'),
        ('KFC', 'KFC'),
      ]
    SHOP3_CHOICES = [
        ('Bowling Arena', 'Bowling Arena'),
        ('Cinemax', 'Cinemax'),
      ]
    return choice( SHOP1_CHOICES + SHOP3_CHOICES )   # choose one

最后，动态选择的模型：

Finally the model with dynamic choices:

class Feed(models.Model):
  ...
  location=models.CharField(max_length=25, choices=SHOP1_CHOICES)

  def __init__(self, *args, **kwargs):
     super(Feed, self).__init__(*args, **kwargs)
     self._meta.get_field_by_name('location')[0]._choices = \
                        lazy(help_SHOP_CHOICES,list)()

由@radtek建议编辑

相反，

    return choice( SHOP1_CHOICES, SHOP3_CHOICES )  # choose one

看到：

    return choice( SHOP1_CHOICES + SHOP3_CHOICES )  # choose one

这篇关于Django模型中的动态选择字段的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！