Fonction de barrage du mini-programme WeChat

<!-- pages/index/index.wxml -->
<swiper indicator-dots="{{indicatorDots}}"
 autoplay="{{autoplay}}" interval="{{interval}}" duration="{{duration}}">
 <block wx:for="{{imgUrls}}" wx:key="unique">
  <swiper-item>
   <image src="{{item}}" class="slide-image"/>
  </swiper-item>
 </block>
</swiper>

<!--弹幕开关-->
<view class="barrage-Switch" style="color:{{barrageTextColor}};">
  <switch id="switch_" bindchange="barrageSwitch"/>
  <text>弹幕</text>
</view>

<!--弹幕输入框-->
 <view class="barrage-inputText" style="display:{{barrage_inputText}}">
   <view class="barrage-input">
    <input bindblur="bind_shoot" value="{{bind_shootValue}}"/>
   </view>
   <view class="barrage-shoot">
     <button class="shoot" size="mini" bindtap="shoot">发射</button>
   </view>
 </view>

<!--弹幕上单文字-->
<view class="barrage-fly" style="display:{{barragefly_display}}">
 <block wx:for="{{barrage_style}}" wx:key="unique">
  <text class="barrage-textFly" style="color:{{item.barrage_shoottextColor}};left:{{item.barrage_phoneWidth}}px;top:{{item.barrageText_height}}px;">{{item.barrage_shootText}}</text>
 </block>
</view>

/* pages/index/index.wxss */
.slide-image{
  width: 100%;
}

/* 弹幕选择按钮的操作*/
.barrage-Switch{
  position: absolute;
  bottom: 10px;
  right: 10px;
  z-index: 2;
}

/* 弹幕输入框的操作*/
.barrage-inputText{
  position: absolute;
  display: flex;
  background-color: #BFBFBF;
  width: 100%;
  height: 40px;
  flex-direction: row;
  nav-index: 2;
  justify-content: center;
  align-items: center;
  bottom: 10%;
}
.barrage-input{
  background-color: greenyellow;
  width: 60%;
  height: 30px;
}
.barrage-shoot{

  margin-left: 10px;
  width: 25%;
  height: 30px;
}
.shoot{
  width: 100%;
  color: black;
}

/*弹幕飞飞飞*/
.barrage-fly{
  z-index: 3;
  height: 80%;
  width: 100%;
  position: absolute;
  top: 0;
}
.barrage-textFly{
  position: absolute;

}

var barrage_style_arr = [];
var barrage_style_obj ={};
var phoneWidth = 0;
var timers = [];
var timer ;
Page({
 data: {
  imgUrls: [
   'http://img02.tooopen.com/images/20150928/tooopen_sy_143912755726.jpg',
   'http://img06.tooopen.com/images/20160818/tooopen_sy_175866434296.jpg',
   'http://img06.tooopen.com/images/20160818/tooopen_sy_175833047715.jpg'
  ],
  indicatorDots: true,
  autoplay: true,
  interval: 3000,
  duration: 500,
  barrageTextColor:"#D3D3D3",
  barrage_inputText:"none",
  barrage_shoottextColor:"black",
  bind_shootValue:"",
  barrage_style:[],
  barragefly_display:"none",
 },


  // 生命周期函数--监听页面加载
 onLoad:function(options){
  var that = this;
  //获取屏幕的宽度
   wx.getSystemInfo({
    success: function(res) {
      that.setData({
        barrage_phoneWidth:res.windowWidth-100,
      })
    }
   })
   phoneWidth = that.data.barrage_phoneWidth;
   console.log(phoneWidth);
 },

 //是否打开弹幕... 
 barrageSwitch: function(e){
  console.log(e);
  //先判断没有打开
  if(!e.detail.value){
  //清空弹幕
   barrage_style_arr = [];
   //设置data的值
   this.setData({
    barrageTextColor:"#D3D3D3",
    barrage_inputText:"none",
    barragefly_display:"none",
    barrage_style:barrage_style_arr,
   });
   //清除定时器
   clearInterval(timer);
  }else{
   this.setData({
    barrageTextColor:"#04BE02",
    barrage_inputText:"flex",
    barragefly_display:"block",
   });
   //打开定时器
    timer= setInterval(this.barrageText_move,800)
  }
 },

 //发射按钮
 shoot: function(e){

  //字体颜色随机
  var textColor = "rgb("+parseInt(Math.random()*256)+","+parseInt(Math.random()*256)+","+parseInt(Math.random()*256)+")";
  // //设置弹幕字体的水平位置样式
  // var textWidth = -(this.data.bind_shootValue.length*0);
  //设置弹幕字体的垂直位置样式
  var barrageText_height = (Math.random())*266;
   barrage_style_obj = {
   // textWidth:textWidth,
   barrageText_height:barrageText_height,
   barrage_shootText:this.data.bind_shootValue,
   barrage_shoottextColor : textColor,
   barrage_phoneWidth:phoneWidth
  };
  barrage_style_arr.push(barrage_style_obj);
  this.setData({ 
   barrage_style:barrage_style_arr,    //发送弹幕
   bind_shootValue:""          //清空输入框
  })

   //定时器 让弹幕动起来
   // this.timer= setInterval(this.barrageText_move,800);

 },

//定时器 让弹幕动起来
 barrageText_move: function(){
  var timerNum = barrage_style_arr.length;
  var textMove ;
  for(var i=0;i<timerNum;i++){
    textMove = barrage_style_arr[i].barrage_phoneWidth;
    console.log("barrage_style_arr["+i+"].barrage_phoneWidth----------:"+barrage_style_arr[i].barrage_phoneWidth);
    textMove = textMove -20;
   barrage_style_arr[i].barrage_phoneWidth = textMove;
   //走完的移除掉
   if(textMove<=-100){
 //     clearTimeout(this.timer);
     barrage_style_arr.splice(0,1);
     i--;
     //全部弹幕运行完
     if(barrage_style_arr.length==0){
      this.setData({
       barrage_style:barrage_style_arr, 
      })
      // clearInterval(this.timer);
      return;
     }
   }
   console.log("第"+i+"个定时器:",textMove);
   this.setData({
    barrage_style:barrage_style_arr, 
   })
  }


 },

 //绑定发射输入框，将值传递给data里的bind_shootValue，发射的时候调用
 bind_shoot:function(e){
  this.setData({
   bind_shootValue:e.detail.value
  })
 },

})

 barrageSwitch: function(e){
  console.log(e);
 }

<switch id="switch_" bindchange="barrageSwitch"/>

 Object {type: "change", timeStamp: 2766, target: Object, currentTarget: Object, detail: Object}