Question

我发现这个代码用于进度条圈，但是这段代码只创建了一个进度条圈。

我需要创建更多的进度条。

此代码：

<div class="chart" id="graph" data-percent="88"></div>

JS

var el = document.getElementById('graph'); // get canvas

var options = {
    percent:  el.getAttribute('data-percent') || 25,
    size: el.getAttribute('data-size') || 220,
    lineWidth: el.getAttribute('data-line') || 15,
    rotate: el.getAttribute('data-rotate') || 0
}

var canvas = document.createElement('canvas');
var span = document.createElement('span');
span.textContent = options.percent + '%';

if (typeof(G_vmlCanvasManager) !== 'undefined') {
    G_vmlCanvasManager.initElement(canvas);
}

var ctx = canvas.getContext('2d');
canvas.width = canvas.height = options.size;

el.appendChild(span);
el.appendChild(canvas);

ctx.translate(options.size / 2, options.size / 2); // change center
ctx.rotate((-1 / 2 + options.rotate / 180) * Math.PI); // rotate -90 deg

//imd = ctx.getImageData(0, 0, 240, 240);
var radius = (options.size - options.lineWidth) / 2;

var drawCircle = function(color, lineWidth, percent) {
        percent = Math.min(Math.max(0, percent || 1), 1);
        ctx.beginPath();
        ctx.arc(0, 0, radius, 0, Math.PI * 2 * percent, false);
        ctx.strokeStyle = color;
        ctx.lineCap = 'round'; // butt, round or square
        ctx.lineWidth = lineWidth
        ctx.stroke();
};

drawCircle('#efefef', options.lineWidth, 100 / 100);
drawCircle('#555555', options.lineWidth, options.percent / 100);

谢谢。

Answer 1

你已经完成了艰苦的工作。将代码包装在一个接受DOM元素并根据它创建圆的函数中。

var elems = document.querySelectorAll('.chart'); // get canvas
elems.forEach(function(el) {
  createCircle(el);
})

function createCircle(el) {
  //Logic to create circle
}

var elems = document.querySelectorAll('.chart'); // get canvas
elems.forEach(function(el) {
  createCircle(el);
})

function createCircle(el) {
  var options = {
    percent: el.getAttribute('data-percent') || 25,
    size: el.getAttribute('data-size') || 220,
    lineWidth: el.getAttribute('data-line') || 15,
    rotate: el.getAttribute('data-rotate') || 0
  }

  var canvas = document.createElement('canvas');
  var span = document.createElement('span');
  span.textContent = options.percent + '%';

  if (typeof(G_vmlCanvasManager) !== 'undefined') {
    G_vmlCanvasManager.initElement(canvas);
  }

  var ctx = canvas.getContext('2d');
  canvas.width = canvas.height = options.size;

  el.appendChild(span);
  el.appendChild(canvas);

  ctx.translate(options.size / 2, options.size / 2); // change center
  ctx.rotate((-1 / 2 + options.rotate / 180) * Math.PI); // rotate -90 deg

  //imd = ctx.getImageData(0, 0, 240, 240);
  var radius = (options.size - options.lineWidth) / 2;

  var drawCircle = function(color, lineWidth, percent) {
    percent = Math.min(Math.max(0, percent || 1), 1);
    ctx.beginPath();
    ctx.arc(0, 0, radius, 0, Math.PI * 2 * percent, false);
    ctx.strokeStyle = color;
    ctx.lineCap = 'round'; // butt, round or square
    ctx.lineWidth = lineWidth
    ctx.stroke();
  };

  drawCircle('#efefef', options.lineWidth, 100 / 100);
  drawCircle('#555555', options.lineWidth, options.percent / 100);
}

div {
  position: relative;
  margin: 80px;
  width: 220px;
  height: 220px;
}

canvas {
  display: block;
  position: absolute;
  top: 0;
  left: 0;
}

span {
  color: #555;
  display: block;
  line-height: 220px;
  text-align: center;
  width: 220px;
  font-family: sans-serif;
  font-size: 40px;
  font-weight: 100;
  margin-left: 5px;
}

input {
  width: 200px;
}

span {}

<div class="chart" data-percent="88"></div>
<div class="chart" data-percent="32"></div>

Update Fiddle

如何创建多个循环进度条？

1 个答案: