Uniapp编写微信小程序，绘制动态圆环进度条

一、完整代码：

<template><view class=\"home\"><view><!-- 标题tab --><view class=\"title\">我是标题</view></view><scroll-view scroll-y style=\"height: calc(100vh - 360rpx)\"><view class=\"chartBox\"><view class=\"chartBox-progress\"><canvas canvas-id=\"progressCanvas\":style=\"{width: canvasSize +iconSize*2 + \'px\', height: canvasSize +iconSize*2 + \'px\'}\"></canvas></view><view class=\"content\"><view class=\"content-value\"><view class=\"value\">{{info.progress}}</view><view class=\"text\">%</view></view><view class=\"content-tips\"><view class=\"text\">预计还需</view><view class=\"value\">{{info.remainingTime}}分钟</view></view></view></view></scroll-view></view></template><script>export default {data() {return {ctx: null,iconImage: \'/static/monitor/cg.png\',canvasSize: 208,iconSize: 34,ringWidth: 9,imagePath: \'\',imageLoaded: false,info: {progress: 0, // 初始化进度totalTime: 60, // 总时间（分钟）remainingTime: 60, // 剩余时间}}},watch: { // 监听进度变化，重绘圆环progress() {this.drawProgress();}},components: {},onLoad() {this.initCanvas();this.loadImage();this.simulateCharging();},methods: {initCanvas() {// 获取Canvas上下文this.ctx = uni.createCanvasContext(\'progressCanvas\', this);},loadImage() {// 检查是否为本地资源if (this.iconImage.startsWith(\'/\') || this.iconImage.startsWith(\'./\')) {// 本地资源直接使用this.imagePath = this.iconImage;this.imageLoaded = true;this.drawProgress();} else {// 网络资源需要先下载uni.getImageInfo({src: this.iconImage,success: (res) => {this.imagePath = res.path;this.imageLoaded = true;this.drawProgress();},fail: (err) => {console.error(\'获取图片信息失败:\', err);this.drawProgress();}});}},drawProgress() {// 计算总画布尺寸（包含图标空间）const totalSize = this.canvasSize + this.iconSize * 2;// 计算真正的中心点const center = totalSize / 2;// 计算圆环半径const radius = (this.canvasSize - this.ringWidth) / 2;// 清空画布this.ctx.clearRect(0, 0, totalSize, totalSize+ this.iconSize);// 绘制背景圆环this.drawInnerShadow(this.ctx, center, radius, this.ringWidth);this.ctx.beginPath();this.ctx.arc(center, center - this.iconSize / 2, radius, 0, Math.PI * 2);this.ctx.setStrokeStyle(\'#ffd1bf\');this.ctx.setLineWidth(this.ringWidth);this.ctx.stroke();// 绘制进度圆环this.ctx.beginPath();const startAngle = -Math.PI / 2; // 从12点位置开始const endAngle = startAngle + (this.info.progress / 100) * (Math.PI * 2);this.ctx.arc(center, center - this.iconSize / 2, radius, startAngle, endAngle);this.ctx.setStrokeStyle(\'#FF6D33\');this.ctx.setLineWidth(this.ringWidth);this.ctx.stroke();// 计算图标位置const iconAngle = startAngle + (this.info.progress / 100) * (Math.PI * 2);const iconX = center + Math.cos(iconAngle) * radius;const iconY = center + Math.sin(iconAngle) * radius;this.ctx.save();if (this.imageLoaded) {// 绘制图标（修正坐标计算）this.ctx.drawImage(this.imagePath,iconX - this.iconSize / 2, // 左顶点X = 中心点X - 图标宽度/2iconY - this.iconSize, // 上顶点Y = 中心点Y - 图标高度/2this.iconSize,this.iconSize);} else {// 图标加载失败时显示默认图标this.ctx.beginPath();this.ctx.arc(iconX, iconY, this.iconSize / 2, 0, Math.PI * 2);this.ctx.setFillStyle(\'#FF6D33\');this.ctx.fill();}this.ctx.restore();this.ctx.draw();// 更新剩余时间this.info.remainingTime = Math.round((100 - this.info.progress) * this.info.totalTime / 100);},drawInnerShadow(ctx, center, radius, ringWidth) {const shadowColor = \'rgba(255, 209, 191, 0.15)\';const shadowWidth = 6;// 绘制外环阴影ctx.beginPath();ctx.arc(center, center- this.iconSize / 2, radius + ringWidth / 2 + shadowWidth / 2, 0, Math.PI * 2);ctx.setFillStyle(shadowColor);ctx.fill();// 绘制内环阴影（覆盖内部区域）ctx.beginPath();ctx.arc(center, center- this.iconSize / 2, radius - ringWidth / 2 - shadowWidth / 2, 0, Math.PI * 2);ctx.setFillStyle(\'#ffffff\');ctx.fill();},onImageLoad() {// 图片加载成功this.imageLoaded = true;this.drawProgress();},// 模拟进度更新simulateCharging() {if (this.info.progress < 100) {setTimeout(() => {this.info.progress += 1;this.drawProgress();this.simulateCharging();}, 100);}}}}</script><style scoped>.home {position: relative;width: 100vw;height: 100vh;background: #ecf0f1;}.home .chartBox {position: relative;left: 50%;top: 128rpx;transform: translateX(-50%);width: 480rpx;height: 480rpx;background: linear-gradient(180deg, #FFFFFF 0%, #fff8f6 100%);box-shadow: 0rpx 20rpx 20rpx 0rpx rgba(255, 209, 191, 0.1);border-radius: 100%;}.home .chartBox-progress {z-index: 2;position: relative;overflow: visible !important;display: flex;flex-direction: column;align-items: center;justify-content: center;height: 480rpx;}.home .content {z-index: 9;position: absolute;top: 144rpx;left: 50%;transform: translateX(-50%);display: flex;flex-direction: column;align-items: center;}.home .content-value {display: flex;align-items: baseline;flex-wrap: nowrap;}.home .content-value .value {font-weight: 500;font-size: 120rpx;color: #ff8859;}.home .content-value .text {margin-bottom: 8rpx;font-weight: 400;font-size: 32rpx;color: #ffded1;}.home .content-tips {margin: 0 0 20rpx;}.home .content-tips .text {font-weight: 400;font-size: 24rpx;color: #3F5680;}.home .content-tips .value {margin: 0 8rpx;font-weight: 600;font-size: 24rpx;color: #ff8859;}</style>

二、最终效果：