CRM手记-6 | Django

Posted 2020-10-21 胡说八道

# 排序功能开发；
# 单条件排序;
# 在表头每个字段上都添加a标签,点击降序,记住这次操作,再次点击反序(用箭头图标展示);
    # table_obj_list.html
        <th><a href="?_o=">{{ column }}</a></th>
        # _0等于字段的索引,如果为负,反序;
        # 所以可以通过模板标签forloop.count0来取;
        <th><a href="?_o={{forloop.count0}}">{{ column }}</a></th>
    # 考虑排序与过滤的关系;
    #     即可以过滤后排序,又可以排序后过滤;
    # 先忽略过滤条件,做筛选;
        # views.py
            def get_filter_result(request,querysets):
                filter_conditions = {}
                for key,val in request.GET.items():
                    # 排除分页的影响
                    if key in (‘page‘,‘_o‘):continue
                    if val:
                        filter_conditions[key] = val

                    print("filter_conditions",filter_conditions)
                return querysets.filter(**filter_conditions),filter_conditions

    # 在筛选条件下做筛选搜索;考虑分页,排序,筛选的前后顺序;
    # 先排序再分页！分页后再排序的话,排序不受分页参数影响;==>>全局排序;
        # views.py
            def get_orderby_result(request,querysets,admin_class):
                """排序"""
                field_index = request.GET.get(‘_o‘,‘‘)
                if field_index:
                    # 从list_display中拿到字段名
                    field_name = admin_class.list_filter[int(field_index)]
                    # 获取字段名,根据字段名做正方排序
                    return querysets.order_by(field_name)
                else:
                    return querysets

            @login_required
            def table_obj_list(request,app_name,model_name):
                ...
                # 排序
                querysets = get_orderby_result(request,querysets,admin_class)
# 只有单方向排序;
# 怎么记住上次排序？再次点击做反方向排序;考虑-0的情况;
    # views.py
        @login_required
        def table_obj_list(request,app_name,model_name):
            ...
            # 排序后端数据查询
            querysets,current_order_field = get_orderby_result(request,querysets,admin_class)
            ...

            return render(request,‘kingadmin/table_obj_list.html‘, {
                ‘querysets‘:querysets,
                ‘admin_class‘:admin_class,
                ‘current_page‘:current_page,
                ‘current_order_field‘:current_order_field
            })
    
        def get_orderby_result(request,querysets,admin_class):
            """排序"""
            # 1.从url中获取排序下表参数
            field_index = request.GET.get(‘_o‘,‘‘)
            current_order_field = {}
            # 2.判断是否已经排序
            if field_index:
                print("当前下标:%s"%field_index)
                # 2.1 如果有排序,根据下标绝对值从list_display中拿到字段名;
                field_name = admin_class.list_display[abs(int(field_index))]
                print(‘当前排序字典:%s‘%field_name)
                # kingadmin_tags.order_handle 中需要的数据:用于前端获知当前字段上次排序参数正负情况;
                current_order_field[field_name] = field_index
                print(‘当前访问后的字典:%s‘%current_order_field)
                # 4.如果排序的参数为负数,做反序查询
                if field_index.startswith(‘-‘):
                    field_name = ‘-‘+field_name
                # 5.返回排序后的查询对象
                return querysets.order_by(field_name),current_order_field
            # 2.2　如果没有排序,返回原始查询集
            else:
                return querysets,current_order_field

    # table_obj_list.html
        <thead>
            <tr>
            {% if admin_class.list_display %}
                {% for column in admin_class.list_display %}
                    <th><a href="?_o={% get_order_factor column current_order_field forloop.counter0 %}">
                        {{ column }}</a>
                    </th>
                {% endfor %}
                {% else %}
                <th>{% get_model_name admin_class %}</th>
            {% endif %}
            </tr>
        </thead>
    # kingadmin_tag.py
        @register.simple_tag
        def get_order_factor(column,current_order_field,forloop):
            """前端访问参数设置,访问后参数取反"""
            # 1.判断当前列是否排序
            #   前端怎么知道当前列是否已经排序？需要记住上次访问传入的参数;
            #   后端在处理一次排序之后,将此次排序参数依据存在一个字典中,然后传到前端做判断;
            if column in current_order_field:
                # print(‘current_order_field:%s column:%s‘%(current_order_field,column))
                last_sort_index = current_order_field[column]
                print(‘已经点击的链接中下标:%s‘%last_sort_index)
                if last_sort_index.startswith(‘-‘):
                    current_sort_index = last_sort_index.strip(‘-‘)
                else:
                    current_sort_index = ‘-%s‘%last_sort_index
                print(‘生成下次点击的下标:%s‘%current_sort_index)
                return current_sort_index
            else:
                return forloop

# 增加排序标志
    # table_obj_list.html
        <span class="glyphicon glyphicon-triangle-{% arror_direction current_order_field column %}" aria-hidden="true"></span>
    # kingadmin_tag.py
        # 箭头方向展示
        @register.simple_tag
        def arror_direction(current_order_field,column):
            arror_direction = ‘‘
            # 先判断是否已经排序
            if column in current_order_field:
                print(‘column:%s‘%column)
                if current_order_field[column].startswith(‘-‘):
                    arror_direction = ‘top‘
                else:
                    arror_direction = ‘bottom‘
            return arror_direction
    # 附:注意要有bootstrap的fonts文件才可以显示箭头;