当前位置:源码库-建站教程-网站开发-JavaScript/Ajax教程-原生js实现的移动端可拖动进度条插件功能详解

原生js实现的移动端可拖动进度条插件功能详解

时间:2019-08-15来源/作者:我站在山顶上 编辑:源码库 文章热度:

本文实例讲述了原生js实现的移动端可拖动进度条插件功能。分享给大家供大家参考,具体如下:

该插件最初的想法来自网上的一篇文章,直达链接:http://www.aspku.com/kaifa/javascript/352204.html

笔者因为业务需要寻找到这个插件,然后拿来用之,发现各种不方便,然后便开始了改造之路。

上代码:

<script>
    function dragSlide(id) {
      this.minDiv =document.getElementById(id); //小方块 
      this.width = parseInt(window.getComputedStyle(this.minDiv, null).width); //小方块的宽度
      this.lineDiv = this.minDiv.parentNode; //长线条
      //滑动的数值呈现
      this.vals = this.minDiv.children[0];
      var that=this;
      var move = function(e) {
        var x = e.touches[0].pageX;
        var lineDiv_left = that.getPosition(that.lineDiv).left; //长线条的横坐标
        var minDiv_left = x - lineDiv_left; //小方块相对于父元素(长线条)的left值
        if (minDiv_left >= that.lineDiv.offsetWidth - that.width) {
          minDiv_left = that.lineDiv.offsetWidth - that.width;
        }
        if (minDiv_left <0 ) {
          minDiv_left = 0;
        }
        //设置拖动后小方块的left值
        that.minDiv.style.left = minDiv_left + "px";
        //percent百分比改为如下所示,解决开始和最后滑动的体验不好问题
        var percent = (minDiv_left / (that.lineDiv.offsetWidth - that.width)) * 100;
        if (percent > 0 && percent < 0.5) {
          percent = Math.ceil(percent);
        } else {
          percent = Math.floor(percent);
        }
        that.vals.innerText = percent;
      }
      //获取元素的绝对位置,工具函数
      this.getPosition = function(node) {
        var left = node.offsetLeft; //获取元素相对于其父元素的left值var left
        var top = node.offsetTop;
        current = node.offsetParent; // 取得元素的offsetParent
          // 一直循环直到根元素
          
        while (current != null) {  
          left += current.offsetLeft;  
          top += current.offsetTop;  
          current = current.offsetParent;  
        }
        return {
          "left": left,
          "top": top
        };
      }
      this.minDiv.addEventListener("touchmove", move);
    }
    var drag0 = new dragSlide("minDiv");
    var drag1 = new dragSlide("minDiv1");
    //取消移动端手势长按弹出提示框的操作
    document.addEventListener('contextmenu', function(e) {
      e.preventDefault();
    });
</script>

html和css部分没有改动,而js改动还是很大的,比较原来作者的文章,改动点如下

1)整体上,原来不是插件,改造之后成为一个可以复用的插件,虽然简单了点

2)只是将其改造为适用于移动端的插件

3)通过对开始滑动和结束滑动比例的处理,优化了开始滑动和结束滑动的体验

4)移动端加了防止长按弹出提示框的代码

5)小滑块的宽度改为动态

改造之后的整体案例,需要指出:笔者主要用在微信端,至于其他浏览器滑块的体验不是很好,还有滑块滑动体验跟小块的尺寸有直接关系。

<!DOCTYPE html>
<html lang="zh-cn">
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
  <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no" />
  <title>鼠标拖动小方块</title>
  <style type="text/css">
  .lineDiv {
    position: relative;
    height: 5px;
    background: red;
    width: 300px;
    margin: 50px auto;
  }
  .lineDiv .minDiv {
    position: absolute;
    top: -12.5px;
    left: 0;
    width: 30px;
    height: 30px;
    background: green;
    cursor: pointer
  }
  .lineDiv .minDiv .vals {
    position: absolute;
    font-size: 20px;
    top: -45px;
    left: -2.5px;
    width: 35px;
    height: 35px;
    line-height: 35px;
    text-align: center;
    background: blue;
  }
  .lineDiv .minDiv .vals:after {
    content: "";
    width: 0px;
    height: 0px;
    border-top: 6px solid blue;
    border-left: 6px solid transparent;
    border-right: 6px solid transparent;
    border-bottom: 6px solid transparent;
    display: block;
    margin-left: 11px;
  }
  * {
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
  }
  </style>
</head>
<body>
  <center>
    <h3>用鼠标拖动小方块<span id="msg">0</span>%</h3>
  </center>
  <div id="lineDiv" class="lineDiv">
    <div id="minDiv" class="minDiv">
      <div id="vals" class="vals">0</div>
    </div>
  </div>
  <div style="height: 20px;"></div>
  <div id="lineDiv" class="lineDiv">
    <div id="minDiv1" class="minDiv">
      <div id="vals" class="vals">0</div>
    </div>
  </div>
  <script>
  //避免默认事件 2018.7.10 更新 优化uc浏览器左右滑动时候页面被拖动
  document.addEventListener('touchmove', function(e) {
    e.preventDefault();
  }, { passive: false });
  function dragSlide(id) {
    this.minDiv = document.getElementById(id); //小方块 
    this.width = parseInt(window.getComputedStyle(this.minDiv, null).width); //小方块的宽度
    this.lineDiv = this.minDiv.parentNode; //长线条
    //滑动的数值呈现
    this.vals = this.minDiv.children[0];
    var that = this;
    var lastX = null; //判断鼠标移动方向,解决向左侧滑动时候的bug
    var move = function(e) {
      var x = e.touches[0].pageX,
        direction = '';
      if (lastX == null) {
        lastX = x;
        return;
      }
      if (x > lastX) {
        direction = 'right';
      } else if (x < lastX) {
        direction = 'left';
      } else {
        direction = '';
      }
      var lineDiv_left = that.getPosition(that.lineDiv).left; //长线条的横坐标
      var minDiv_left = x - lineDiv_left; //小方块相对于父元素(长线条)的left值
      if (minDiv_left >= that.lineDiv.offsetWidth - that.width) {
        minDiv_left = that.lineDiv.offsetWidth - that.width;
      }
      if (minDiv_left < 0) {
        minDiv_left = 0;
      }
      //设置拖动后小方块的left值
      that.minDiv.style.left = minDiv_left + "px";
      //percent百分比改为如下所示,解决开始和最后滑动的体验不好问题
      var percent = (minDiv_left / (that.lineDiv.offsetWidth - that.width)) * 100;
      if (percent < 0.5 && direction == 'right') {
        percent = Math.ceil(percent);
      } else if (percent > 0.5 && direction == 'right') {
        percent = Math.floor(percent);
      } else {
        percent = Math.ceil(percent);
      }
      that.vals.innerText = percent;
    }
    //获取元素的绝对位置,工具函数
    this.getPosition = function(node) {
      var left = node.offsetLeft; //获取元素相对于其父元素的left值var left
      var top = node.offsetTop;
      current = node.offsetParent; // 取得元素的offsetParent
        // 一直循环直到根元素
        
      while (current != null) {  
        left += current.offsetLeft;  
        top += current.offsetTop;  
        current = current.offsetParent;  
      }
      return {
        "left": left,
        "top": top
      };
    }
    this.minDiv.addEventListener("touchmove", move);
  }
  var drag0 = new dragSlide("minDiv");
  var drag1 = new dragSlide("minDiv1");
  //取消移动端手势长按弹出提示框的操作
  document.addEventListener('contextmenu', function(e) {
    e.preventDefault();
  });
  </script>
</body>
</html>

 

希望本文所述对大家JavaScript程序设计有所帮助。


注:相关教程知识阅读请移步到JavaScript/Ajax教程频道。
相关JavaScript/Ajax教程
热门标签

JavaScript/Ajax教程Rss订阅JavaScript/Ajax教程搜索