使用Django admin创建自定义列

Question

我有一个名为Data的模型，它关联到这样一张表（模型Data只由IntegerField组成）：

subject | year | quarter | sales |
----------------------------------
   1    | 2010 |   1     | 20    |
   1    | 2010 |   2     | 100   |
   1    | 2010 |   3     | 100   |
   1    | 2010 |   4     | 20    |
   1    | 2011 |   1     | 30    |
   1    | 2011 |   2     | 50    |
   1    | 2011 |   4     | 40    |
   2    | 2010 |   1     | 30    |
   2    | 2010 |   2     | 20    |
 [..-GO ON this way...]

我想要一个只读的 Django 管理页面，其中包含列 (当前年份=2011，季度=1)。

subject | sales current year | sales current quarter | sales last year | sales current quarter last year |
----------------------------------------------------------------------------------------------------------
  1     |  110               |  30                   |  240            |  20
[AND SO ON]

问题是：使用django-admin可以实现吗？有什么解决办法？

- zambotn

Answer 1

你可以在list_display中使用你的Model或者ModelAdmin的方法作为项。请参见：https://docs.djangoproject.com/en/dev/ref/contrib/admin/#django.contrib.admin.ModelAdmin.list_display

由于这些方法可能也有用途在admin之外，我建议将它们添加到你的Model中。

from django.db.models import Sum

class Data(models.Model):
    ...

    # Method used by `get_current_year_sales` and `get_last_year_sales`
    # to stay DRY. Not for use directly in admin.
    def get_year_sales(self, year):
        qs = self.model._default_manager.filter(year=year)
        sales_agg = qs.aggregate(Sum('sales'))
        return sales_agg['sales__sum']

    # Method used by `get_current_quarter_sales` and `get_last_quarter_sales`
    # to stay DRY. Not for use directly in admin.
    def get_quarter_sales(self, year, quarter):
        qs = self.model._default_manager.filter(year=year, quarter=quarter)
        sales_agg = qs.aggregate(Sum('sales'))
        return sales_agg['sales__sum']

    def get_current_year_sales(self):
        return self.get_year_sales(datetime.now().year)
    get_current_year_sales.short_description = 'Sales (Current Year)'

    def get_last_year_sales(self):
        return self.get_year_sales(datetime.now().year-1)
    get_last_year_sales.short_description = 'Sales (Last Year)'

    def get_current_quarter_sales(self):
        # Determine current quarter logic here as `current_quarter`
        # `quarter_year` will likely be same as current year here,
        # but will need to be calculated for previous quarter
        return self.get_quarter_sales(quarter_year, current_quarter)
    get_current_quarter_sales.short_description = 'Sales (Current Quarter)'

    def get_current_quarter_sales(self):
        # Logic here to determine last quarter as `last_quarter`
        # Logic to determine what year last quarter was in as `quarter_year`
        return self.get_quarter_sales(quarter_year, last_quarter)
    get_last_quarter_sales.short_description = 'Sales (Last Quarter)'

short_description 属性确定管理员将显示哪些方法的行标题。因此，一旦您完成所有这些步骤，您只需要修改您的 ModelAdmin 的 list_display 属性，如下所示：

class DataAdmin(admin.ModelAdmin):
    ...
    list_display = ('subject', 'get_current_year_sales', 'get_last_year_sales', 'get_current_quarter_sales', 'get_last_quarter_sales')

- Chris Pratt

---

最后一个问题，如果我想对列进行排序，它不起作用，因为这些是方法而不是属性，对吗？谢谢！ - zambotn

请查看这个和这个。 - dan-klasson

可以通过告诉Django使用<method>.admin_order_field = 'my_field'来添加排序功能，但在这种情况下，没有真正好的字段可以绑定它。 - Chris Pratt

如果新列没有显示出来，请尝试重新启动Django服务器。 - Ryan Allen

我该如何为这个自定义字段“get_current_year_sales”设置标签，例如“当年销售额”（不包括“get”）？ - YaserKH

Answer 2

这样的代码应该可以工作（未经测试）：

# models.py
class Data(models.Model):
    year = models.DateField()
    sales = models.IntegerField()
    # ...

    def sales_current_year(self):
        return self.model._default_manager.get_queryset().filter(year=2012).annotate(Sum('sales'))

 # admin.py
 class DataAdmin(admin.ModelAdmin):
      list_display = ('sales_current_year',)

- dan-klasson