确定进度条上的点击位置？

Question

是否可以使用普通的javascript确定用户点击进度条的值/位置？

目前，我可以检测到元素上的点击，但只能获取栏的当前位置，与用户的点击无关。

http://jsfiddle.net/bobbyrne01/r9pm5Lzw/

HTML

<progress id="progressBar" value="0.5" max="1"></progress>

JS

document.getElementById('progressBar').addEventListener('click', function () {
    alert('Current position: ' + document.getElementById('progressBar').position);
    alert('Current value: ' + document.getElementById('progressBar').value);
});

Answer 1

你可以得到你在元素里面点击的坐标，如下所示：

只需从点击页面的坐标中减去元素的偏移位置即可。

Updated Example

document.getElementById('progressBar').addEventListener('click', function (e) {
    var x = e.pageX - this.offsetLeft, // or e.offsetX (less support, though)
        y = e.pageY - this.offsetTop,  // or e.offsetY
        clickedValue = x * this.max / this.offsetWidth;

    console.log(x, y);
});

如果要确定click事件是否发生在值范围内，则必须将单击的值（与元素的宽度相关）与progress元素上设置的value属性进行比较：

Example Here

document.getElementById('progressBar').addEventListener('click', function (e) {
    var x = e.pageX - this.offsetLeft, // or e.offsetX (less support, though)
        y = e.pageY - this.offsetTop,  // or e.offsetY
        clickedValue = x * this.max / this.offsetWidth,
        isClicked = clickedValue <= this.value;
    
    if (isClicked) {
        alert('You clicked within the value range at: ' + clickedValue);
    }
});

<p>Click within the grey range</p>
<progress id="progressBar" value="5" max="10"></progress>

Answer 2

我测试了你的项目，尝试这个解决方案：

document.getElementById('progressBar').addEventListener('click', function (e) {
    var x = e.pageX - this.offsetLeft;
    
    //Uncomment the following line to activate alert
    //alert('Current position: ' + document.getElementById('progressBar').position);
    
    //Save position before the click
    var startPos = document.getElementById('progressBar').position;
    
    //Convert x value to progress range [0 1]
    
    var xconvert = x/300; //cause width is 300px and you need a value in [0,1] range
    var finalx = (xconvert).toFixed(1); //round up to one digit after coma
    
    //Uncomment the following line to activate alert
    //alert('Click value: ' + finalx);
  
    //If you don't want change progress bar value after click comment the following line
    document.getElementById('progressBar').value = finalx;
    
    document.getElementById('result').innerHTML = ('Start position: ' + startPos + "<br/><br/>");
    document.getElementById('result').innerHTML += ('Current position: ' + document.getElementById('progressBar').position + "<br/>");
    document.getElementById('result').innerHTML += ('Current value: ' + document.getElementById('progressBar').value + "<br/></br/>");
    document.getElementById('result').innerHTML += ('Real click value: ' + xconvert + "<br/>");
    document.getElementById('result').innerHTML += ('Current value set in progressbar: ' + finalx + "<br/>");
});

#progressBar {
    width:300px;
}

<progress id="progressBar" value="0.5" max="1"></progress>
<div id="result"></div>

• 我将进度条宽度设置为300px（您可以更改它）
• 获取进度条中的位置x
• 将x位置范围从[0,300]转换为[0,1]
• 更改进度条内的值

输出：

• 开始位置
• 当前位置和价值（点击后）
• 实际点击价值（未四舍五入）
• 进度条中设置的值（向上舍入）

工作演示：http://jsfiddle.net/Yeti82/c0qfumbL

感谢bobbyrne01更新更正！

Answer 3

$(document).ready(function() {

  $(".media-progress").on("click", function(e) {

    var max = $(this).width(); //Get width element
    var pos = e.pageX - $(this).offset().left; //Position cursor
    var dual = Math.round(pos / max * 100); // Round %


    if (dual > 100) {
      var dual = 100;
    }


    $(this).val(dual);
    $("#progress-value").text(dual);

  });
  
  
  });

.media-progress {
  /*BG*/
  position: relative;
  width: 75%;
  display: inline-block;
  cursor: pointer;
  height: 14px;
  background: gray;
  border: none;
  vertical-align: middle;
}

.media-progress::-webkit-progress-bar {
  /*Chrome-Safari BG*/
  background: gray;
  border: none
}

.media-progress::-webkit-progress-value {
  /*Chrome-Safari value*/
  background: #17BAB3;
  border: none
}

.media-progress::-moz-progress-bar {
  /*Firefox value*/
  background: #17BAB3;
  border: none
}

.media-progress::-ms-fill {
  /*IE-MS value*/
  background: #17BAB3;
  border: none
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<progress value="5" max="100" class="media-progress"></progress>
<div id="progress-value"></div>

Answer 4

click事件实际上采用包括事件信息的参数，包括点击位置信息。您可以使用它来确定进度条中发生单击的位置。

document.getElementById('progressBar').addEventListener('click', function (event) {

    document.getElementById('result').innerHTML = ('Current position: ' + document.getElementById('progressBar').position + "<br/>");
        document.getElementById('result').innerHTML += ('Current value: ' + document.getElementById('progressBar').value + "<br/>");
        document.getElementById('result').innerHTML += ('Mouse click (absolute): ' + event.offsetX + ", " + event.offsetY + "<br/>");
});

<progress id="progressBar" value="0.5" max="1"></progress>
<div id="result"></div>

Answer 5

如果你想点击一般max值的值（在这种情况下，值介于0和1之间），你只需要一些简单的数学运算。

document.getElementById('progressBar').addEventListener('click', function (e) {

    var value_clicked = e.offsetX * this.max / this.offsetWidth;
    alert(value_clicked);

});

Fiddle