关于#Layui#的问题,如何解决?

请问Layui xmselect 如何通过ajax进行二级联动
                var insXmSel;
                var brand_id = "";
                insXmSel = xmSelect.render({
                    el: '#accountEditBrandSel',
                    data: [],
                    radio: true,  //单选
                    clickClose: true,  //选中关闭下拉
                    name:'brand_id',
                    // toolbar:{show:true},
                    layVerify: 'required',
                    layVerType: 'tips',
                    model: {label: {type: 'text'}},
                    prop:{
                        name:'brand_name',
                        value: 'id',
                    },
                    on: function(data){
                        // var arr = data.arr;
                        // console.log(arr);
                        var change = data.change;
                        console.log(change);
                        // var isAdd = data.isAdd;
                    },
                }); 
                    $.ajax({
                        type: 'post',
                        url: "{:url('/account/brands')}",
                        data: {'id': brand_id},
                        dataType: 'json',
                        async: false,
                        success: function (e) {
                            insXmSel.update({
                            data: e.data,
                            autoRow: true,
                            });
                        },
                        error: function() {
                        layer.close(indexload);/* 关闭加载弹层... */
                        layer.msg(res.message);
                        }
                    }); 
                 // 回显选中品牌
                if (mData && mData.brands) {
                    insXmSel.setValue(mData.brands.map(function (item) {
                        return item.brand_id;
                    }));
                }

                var insXmSel2;
                var platform_id = "";                                            
                insXmSel2 = xmSelect.render({
                    el: '#platformEditParentSel',
                    data: [],
                    name:'platform_id',
                    layVerify: 'required',
                    layVerType: 'tips',
                    radio: true,
                    clickClose: true,
                    initValue: mData ? [mData.platform_id] : [],
                    model: {label: {type: 'text'}},
                    prop:{
                        name:'platform_name',
                        value: 'id',
                    },
                });
                $.ajax({
                    type: 'post',
                    url: "{:url('account/platforms')}",
                    data: {'id': platform_id},
                    dataType: 'json',
                    async: false,
                    success: function (e) {
                        insXmSel2.update({
                        data: e.data,
                        autoRow: true,
                        });
                    },
                    error: function() {
                        layer.close(indexload);/* 关闭加载弹层... */
                        layer.msg(res.message);
                    }
                });
我想要达到的结果

根据一级下拉框选择的值不同,二级下拉框显示的数据自动变化,且当一级下拉框选择的值发生改变时,二级下拉框清空已选择的值