小程序scroll-view 使用

<scroll-view class="box" scroll-x="true" >
  <view class="box-item" >1</view>
  <view class="box-item" >2</view>
  <view class="box-item" >3</view>
</scroll-view>

.box {
    width:100vw;
    height: 200rpx;
    white-space: nowrap;        /*white-space 不能丢*/
    border: 1px solid red;
    box-sizing: border-box
}


.box-item {
    width: 45%;
    height:100%;
    border:2rpx solid green;
    box-sizing: border-box;
    display: inline-block
}