django admin-过滤器

django框架的admin模块,通过list_filter提供给用户自定义分类查询的接口,并且我们可以在原有类的基础上扩展出符合自身应用场景的过滤器。

定义模型

以 Student 模型为准,管理类为 StudentAdmin。

class Student(models.Model):
    id = models.AutoField(primary_key=True)
    first_name = models.CharField(
            max_length=20, verbose_name=u'姓')
    last_name = models.CharField(
            max_length=20, verbose_naem=u'名')
    gender = models.IntegerField(
            choices=choices_gender, verbose_name=u'性别')
    age = models.IntegerField(
            blank=True, verbose_name=u'年龄')
    birthday = models.DateTimeField(
            blank=True, verbose_name=u'生日')
@admin.register(Student)
class StudentAdmin(admin.ModelAdmin):
    list_display = ('id', 'first_name', 'last_name', 'gender', 'age', 'birthday')
    list_per_page = 20

mysql创建student表:

CREATE TABLE student(
    id int(10) NOT NULL AUTO_INCREMENT,
    first_name varchar(20) NOT NULL,
    last_name varchar(20) NOT NULL,
    gender int(10) NOT NULL,
    age int(10) NOT NULL,
    birthday datetime,
    PRIMARY KEY (id)
)ENGINE=InnoDB DEFAULT CHARSET=utf8;

直接激活过滤器

过滤器位于Admin页面的右侧,通过 list_filter 可以直接激活 Student 中已经存在的模型。注:list_filter 应该是一个列表或元组。

# 直接激活
list_filter = ('first_name',)

Filter 会自动列出所有不同的姓:

 
1-直接激活.png

当然,其指定的字段应该是BooleanField、CharField、DateField、DateTimeField、IntegerField、ForeignKey 或ManyToManyField中的一种。并且其属性可以为对应关联的外键,通过两个下划线指定关联表中对应属性:FK__key

激活带选项的属性

很多时候,我们的属性只有固定的几种类别,比如性别;一般我们会为该属性绑定选项,这样在展示时也更加直观:

choices_gender = [
    (0, 'male'),
    (1, 'femal'),
]

这时,我们在激活该属性的过滤器,显示的就是选项所对应的值,而不是数据库真正存储的值:

 
2-激活带选项的属性.png

自定义查询的过滤器(SimpleListFilter)

继承自 django.contrib.admin.SimpleListFilter 的类,需要给它提供 titleparameter_name 属性来重写 lookupsqueryset 方法,title为页面上该过滤器的标题、parameter为加载页面时url中携带的参数名称:

from django.utils.translation import ugettext_lazy as _

class AgeListFilter(admin.SimpleListFilter):
    title = _(u'年龄段')
    parameter_name = 'ages'

    def lookups(self, request, model_admin):
        return (
            ('0', _(u'未成年')),
            ('1', _(u'成年人')),
            ('2', _(u'老年人')),
        )
    
    def queryset(self, request, queryset):
        if self.value() == '0':
            return queryset.filter(age__lt='18')
        if self.value() == '1':
            return queryset.filter(age__gte='18', age__lte='50')
        if self.value() == '2':
            return queryset.filter(age__gt='50')
# 激活自定义过滤器
list_filter = (AgeListFilter,)

Filter 会列出 lookups 中定义的选项:

 
3-自定义查询的过滤器.png

日期的区间筛选(DateRangeFilter)

默认的时间筛选只能选取某一段时间至今这样的区间,而daterange_filter插件提供了自定义时间区间的筛选。使用DateRangeFilter 前需要安装插件包 pip install django-daterange-filter,并在settings.pyINSTALLED_APPS 中添加 daterange_filter

list_filter = (('birthday', DateRangeFilter), )
 
4-时间区间的过滤.png

自定义输入框查询(SingleTextInputFilter)

django自带的过滤器是不含输入框的,但是我们可以自己重写一个带输入框的过滤器,并且自己指定样式:

from django.contrib.admin import ListFilter

class SingleTextInputFilter(ListFilter):
    """
    renders filter form with text input and submit button
    """
    parameter_name = None
    template = "textinput_filter.html"

    def __init__(self, request, params, model, model_admin):
        super(SingleTextInputFilter, self).__init__(
            request, params, model, model_admin)
        if self.parameter_name is None:
            raise ImproperlyConfigured(
                "The list filter '%s' does not specify "
                "a 'parameter_name'." % self.__class__.__name__)

        if self.parameter_name in params:
            value = params.pop(self.parameter_name)
            self.used_parameters[self.parameter_name] = value

    def value(self):
        """
        Returns the value (in string format) provided in the request's
        query string for this filter, if any. If the value wasn't provided then
        returns None.
        """
        return self.used_parameters.get(self.parameter_name, None)

    def has_output(self):
        return True

    def expected_parameters(self):
        """
        Returns the list of parameter names that are expected from the
        request's query string and that will be used by this filter.
        """
        return [self.parameter_name]


    def choices(self, cl):
        all_choice = {
            'selected': self.value() is None,
            'query_string': cl.get_query_string({}, [self.parameter_name]),
            'display': _('All'),
        }
        return ({
            'get_query': cl.params,
            'current_value': self.value(),
            'all_choice': all_choice,
            'parameter_name': self.parameter_name
        }, )


class LastNameListFilter(SingleTextInputFilter):
    title = 'Last Name'
    parameter_name = 'last_name'

    def queryset(self, request, queryset):
        if self.value():
            return queryset.filter(last_name=self.value())

将 textinput_filter.html放在templates文件夹下,并在settings.pyTEMPLATES'DIRS',加上templates路径。

{% load i18n %}
<h3>{% blocktrans with filter_title=title %} By {{ filter_title }} {% endblocktrans %}</h3>

{#i for item, to be short in names#}
{% with choices.0 as i %}
<ul>
    <li>
        <form method="get">
            <input type="search" name="{{ i.parameter_name }}" value="{{ i.current_value|default_if_none:"" }}"/>

            {#create hidden inputs to preserve values from other filters and search field#}
            {% for k, v in i.get_query.items %}
                {% if not k == i.parameter_name %}
                    <input type="hidden" name="{{ k }}" value="{{ v }}">
                {% endif %}
            {% endfor %}
            <input type="submit" value="{% trans 'apply' %}">
        </form>
    </li>

    {#show "All" link to reset current filter#}
    <li{% if i.all_choice.selected %} class="selected"{% endif %}>
        <a href="{{ i.all_choice.query_string|iriencode }}">
            {{ i.all_choice.display }}
        </a>
    </li>
</ul>
{% endwith %}
 
5-自定义输入框查询.png


作者:Jerakrs
链接:https://www.jianshu.com/p/09ff09d08f75
来源:简书
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原文地址:https://www.cnblogs.com/feifeifeisir/p/12870225.html