微信小程序组件 marquee实例详解

<marquee direction="left" behavior="scroll" scrollamount="1" scrolldelay="0" loop="-1" width="200" height="50" bgcolor="#0099FF" hspace="10" vspace="10">
   hello world
</marquee>

<view class="marquee_container" style="--marqueeWidth--:{{-marquee.width}}em">
  <view class="marquee_text">{{marquee.text}}</view>
</view>

marquee:{
  width:12,
  text:'hello world'
}

@keyframes around {
  from {
   margin-left: 100%;
  }
  to {
   margin-left: var(--marqueeWidth--);// var接受传入的变量
  }
 }

.marquee_container{
 background-color: #0099FF;
 height: 1.2em;
 position: relative;
 width: 100%;
}
.marquee_container:hover{
 animation-play-state: paused; // 不起作用
}
.marquee_text{
 display: inline-block;
 white-space: nowrap;
 animation-name: around;
 animation-duration: 5s;
 animation-iteration-count: infinite;
 animation-timing-function:linear;
}

export default {
 getWidth:(str)=>{
  return [].reduce.call(str, (pre, cur, index, arr) => {
   if (str.charCodeAt(index) > 255) {// charCode大于255是汉字
    pre++;
   } else {
    pre += 0.5;
   }
   return pre;
  }, 0);
 },
 getDuration:(str)=>{// 保留，根据文字长度设置时间
  return this.getWidth()/10;
 }
}

// wxml
<include src="../ponent/marquee/marquee.wxml" />
// wxss
@import "../ponent/marquee/marquee.wxss";
// js
import marquee from '../ponent/marquee/marquee.js';

var options = Object.assign(marquee, {
 data: {
  motto: 'Hello World',
  userInfo: {},
  marquee: { text: '你好，中国！hello,world!' }
 },
 onLoad: function () {
  // ...

  const str = this.data.marquee.text;
  const width = this.getWidth(str);
  console.log('width',width);
  this.setData({ [`${'marquee'}.width`]: width });
 }
});
Page(options);