微信小程序?qū)崿F(xiàn)文字跑馬燈的方法

<view class="content">
 <text class="every" decode="{{true}}" >{{announ}}</text>
</view>

export default class ShopIndex extends wepy.page {

 config = {
 navigationBarTitleText : '首頁',
 }

 data = {
 // 公告內(nèi)容
 announ : '超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度超長度v',
 announNum : 0,
 announy : 280,
 announZf : '-'
 }

 onLoad() {
 
 let self = this;
 var query = wepy.createSelectorQuery();
 query.select('.content').boundingClientRect(ContentRes => {
  var query = wepy.createSelectorQuery();
  query.select('.every').boundingClientRect(TextRes => {

  //加上一百是因?yàn)榉乐乖跉w零時(shí)出現(xiàn)閃爍的情況
  let maxContentWidth = ContentRes.width + 100,
  maxTextWidth = TextRes.width;
  //初始化
  self.announNum = TextRes.width
  self.$apply();

  //定時(shí)器
  setInterval(()=>{
   if(self.announZf == '-') {
   if(self.announNum <= 0) {
    self.announZf = ''
   } else {
    self.announNum -= 1
   }
   } else {
   if(self.announNum > (maxContentWidth)) {
    //歸位
    self.announZf = '-'
    self.announNum = maxTextWidth
   } else {
    self.announNum += 1
   }
   } 
   self.$apply();  
  },5)
  }).exec();
 }).exec();

 }
 }