<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<style>
body {
color:
}
.box{
position:relative;
height:100vw;
width:100vw;
background: red;
}
.title{
position:absolute;
left:45vw;
bottom:0;
}
#canvas{
width:80vw;
background: skyblue;
}
</style>
<body>
<div class='box'>
<canvas id="canvas" width="300" height="300">
<p>抱歉，您的浏览器不支持canvas</p>
</canvas>
<div class='title'>
拉拉拉啊
</div>
</div>
</body>
</html>
<script>
function toCanvas(id, progress) {
// canvas进度条
var canvas = document.getElementById(id),
ctx = canvas.getContext("2d"),
percent = progress, //最终百分比
circleX = canvas.width / 2, //中心x坐标
circleY = canvas.height / 2, //中心y坐标
radius = 50, //圆环半径
lineWidth = 10, //圆形线条的宽度
fontSize = 30; //字体大小
// 两端圆点
function smallcircle1(cx, cy, r) {
ctx.beginPath();
//ctx.moveTo(cx + r, cy);
ctx.lineWidth = 1;
ctx.fillStyle = '#06a8f3';
ctx.arc(cx, cy, r, 0, Math.PI * 2);
ctx.fill();
}
function smallcircle2(cx, cy, r) {
ctx.beginPath();
//ctx.moveTo(cx + r, cy);
ctx.lineWidth = 10;
ctx.fillStyle = '#00f8bb';
ctx.arc(cx, cy, r, 0, Math.PI * 2);
ctx.fill();
}
//画圆
function circle(cx, cy, r) {
ctx.beginPath();
//ctx.moveTo(cx + r, cy);
ctx.lineWidth = lineWidth;
ctx.strokeStyle = '#eee';
ctx.arc(cx, cy, r, Math.PI * 2 / 3, Math.PI * 1 / 3);
ctx.stroke();
}
// 画弧线
function sector(cx, cy, r, startAngle, endAngle, anti) {
ctx.beginPath();
//ctx.moveTo(cx, cy + r); // 从圆形底部开始画
ctx.lineWidth = lineWidth;
// 渐变色 - 可自定义
var linGrad = ctx.createLinearGradient(
circleX - radius - lineWidth, circleY, circleX + radius + lineWidth, circleY
);
linGrad.addColorStop(0.0, '#06a8f3');
//linGrad.addColorStop(0.5, '#9bc4eb');
linGrad.addColorStop(1.0, '#00f8bb');
ctx.strokeStyle = linGrad;
//圆弧两端的样式
ctx.lineCap = 'round';
//圆弧
ctx.arc(
cx, cy, r,
(Math.PI * 2 / 3),
(Math.PI * 2 / 3) + endAngle / 100 * (Math.PI * 5 / 3),
false
);
ctx.stroke();
}
//刷新
function loading() {
if (process >= percent) {
clearInterval(circleLoading);
}
//清除canvas内容
ctx.clearRect(0, 0, circleX * 2, circleY * 2);
//中间的字
ctx.font = fontSize + 'px April';
ctx.textAlign = 'center';
ctx.textBaseline = 'middle';
ctx.fillStyle = '#999';
ctx.fillText(parseFloat(process).toFixed(0) + '%', circleX, circleY);
//圆形
circle(circleX, circleY, radius);
//圆弧
sector(circleX, circleY, radius, Math.PI * 2 / 3, process);
//两端圆点
// smallcircle1(canvas.width / 2-canvas.width / 2, 150 + Math.sin(2 * Math.PI / 360 * 120) * 100, 10);
// smallcircle2(150 + Math.cos(2 * Math.PI / 360 * (120 + process * 3)) * 100, 150 + Math.sin(Math.PI * 2 / 360 * process * 3) * r, 10);
smallcircle2(150 + Math.cos(Math.PI * 2 / 360 *(120 + process * 3)) * radius, 150 + Math.sin(2 * Math.PI / 360 * (120 + process * 3)) * radius, 10);
//控制结束时动画的速度
if (process / percent > 0.90) {
process += 0.30;
} else if (process / percent > 0.80) {
process += 0.55;
} else if (process / percent > 0.70) {
process += 0.75;
} else {
process += 1.0;
}
}
var process = 0.0; //度
var circleLoading = window.setInterval(function () {
loading();
}, 20);
}
// 第二部分，调用封装好的代码：
toCanvas('canvas', 50);
</script>
</script>