小程序中实现变速大转盘的使用方法浅谈

// index.js

const round = [0,1,2,5,8,7,6,3,0];

let timer ;

Page({

  data: {

    games:['$1','$2','$3','$4','开始','$5','$6','$7','$8'],

    active: 0,

    start: 0,

  },

  onLoad: function (options) {

  },

  beginLottery(){

    this.begin();

  },

  // begin

  begin(){

    let start = this.data.start;

    let random = Math.floor(Math.random()*9);

    let num = 0;

    timer = setInterval(() => {

      start++;

      start = start > 8 ? 0 : start;

      this.setData({

        start,

        active: round[start]

      })

      num++;

      if(num > 24 && this.data.active == random){//

        clearInterval(timer)

      }

    }, 70);

  }

})

//index.js

const round = [0, 1, 2, 5, 8, 7, 6, 3, 0];

let timer; // 定时器

let num = 0; // 用来记录一共转了几次，方便判断转的圈数

let start = 0; // 记录开始的位置下标

let random = ''; // 记录停下来的随机数（下标）

let time = 70; // 记录定时器的时间

let count = 0; // 记录圈数，用来判断每2圈一次变速

Page({

  data: {

    games: ['$1', '$2', '$3', '$4', '开始', '$5', '$6', '$7', '$8'],

    active: 0,

  },

  onLoad: function (options) {},

  beginLottery() {

    this.begin1();

  },

  begin1() {

    if(num != 0){

    // 防止用户重复点击

      return

    }

    timer = setInterval(this.process, time);

  },

  // 旋转的过程

  process() {

    start = start + 1;

    if (start >= 8) {

      start = 0;

      // 当start = 8的时候，表示已经转过1圈了count+1

      count = count + 1;

    }

    this.setData({

      active: round[start]

    })

    num = num + 1;

    // 实现两圈一次变速

    if (num % 8 === 0 && count === 2) {

      count = 0;

      clearInterval(timer);

      time = time + 100;

      timer = setInterval(this.process, time);

      // 转了4圈,即将在第五圈停止

      if (Math.floor(num / 8) === 4) {

        this.getRandom();

      }

    }

    if (this.data.active === random) {

      clearInterval(timer);

      num = 0;

      random = '';

      time = 70;

      count = 0;

    }

  },

  getRandom(){

    let n = Math.floor(Math.random() * 9);

    if(n == 4){

      this.getRandom();

    }else{

      random = n

      return;

    }

  }

})