uni-app项目根据后端返回数据改变元素背景色，使用ref获取不到dom

Question

uni-app项目根据后端返回数据改变元素背景色，使用ref获取不到dom

问题相关代码，请勿粘贴截图

if(data.msg.errcode === 0){
                            that.code = data.msg.position
                        }else if(data.msg.errcode === 40000){
                            that.code = data.msg.errmsg
                            that.$refs.r1.$el.style='background:blue'

Answer 1

 <view class="container" :class="{errorClass: code === 40000}"></view>

.errorClass{background:blue}

if(data.msg.errcode === 0){
  that.code = data.msg.position
}else if(data.msg.errcode === 40000){
   that.code = data.msg.errmsg