微信小程序之实时圆形加载进度条

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概述

今天在网上为大家收集整理来几个非常漂亮的实时圆形加载进度条特效。今天我们就分享这样的小教程。希望对大家有所帮助。

不多说了，二当家要上图来啦！

拿个小板凳，坐等更多更新

注意：如若需要请联系微信geekxz

wxml

<view class="wrap">
  <view class="circle-box">
    <canvas class="circle" style="width:200px; height:200px;" canvas-id="canvasArcCir">
    </canvas>
    <canvas class="circle" style="z-index: -5; width:200px; height:200px;" canvas-id="canvasCircle">
    </canvas>
    <!-- <view class="draw_btn" bindtap="drawCircle">开始动态绘制</view> -->
  </view>
</view>

js

//获取应用实例
var app = getApp()
var interval;
var varName;
var ctx = wx.createCanvasContext('canvasArcCir');
Page({
  data: {
  },
  drawCircle: function () {
    clearInterval(varName);
    function drawArc(s, e) {
      ctx.setFillStyle('white');
      ctx.clearRect(0, 0, 200, 200);
      ctx.draw();
      var x = 100, y = 100, radius = 96;
      ctx.setLineWidth(5);
      ctx.setStrokeStyle('#d81e06');
      ctx.setLineCap('round');
      ctx.beginPath();
      ctx.arc(x, y, radius, s, e, false);
      ctx.stroke()
      ctx.draw()
    }
    var step = 1, startAngle = 1.5 * Math.PI, endAngle = 0;
    var animation_interval = 100, n = 60;
    var animation = function () {
      if (step <= n) {
        endAngle = step * 2 * Math.PI / n + 1.5 * Math.PI;
        drawArc(startAngle, endAngle);
        step++;
      } else {
        clearInterval(varName);
      }
    };
    varName = setInterval(animation, animation_interval);
  },
  onReady: function () {
    //创建并返回绘图上下文context对象。
    var cxt_arc = wx.createCanvasContext('canvasCircle');
    cxt_arc.setLineWidth(6);
    cxt_arc.setStrokeStyle('#eaeaea');
    cxt_arc.setLineCap('round');
    cxt_arc.beginPath();
    cxt_arc.arc(100, 100, 96, 0, 2 * Math.PI, false);
    cxt_arc.stroke();
    cxt_arc.draw();
  },
  onLoad: function (options) {
    this.drawCircle();
  }
})

css

page {
  width: 100%;
  height: 100%;
  background-color: #fff;
}
.circle-box {
  text-align: center;
  margin-top: 10vw;
}
.circle {
  position: absolute;
  left: 0;
  right: 0;
  margin: auto;
}
.draw_btn {
  width: 35vw;
  position: absolute;
  top: 33vw;
  right: 0;
  left: 0;
  margin: auto;
  border: 1px #000 solid;
  border-radius: 5vw;
}