【微信小程序】引用echarts 在真机上预览图表模糊的解决办法

1. 获取移动设备的像素比 获取系统信息 ==> wx.getSystemInfo() API说明：wx.getSystemInfo()

const getPixelRatio = () => {
    let pixelRatio = 0
       wx.getSystemInfo({
          success: function (res) {
           pixelRatio = res.pixelRatio
      },
      fail: function () {
         pixelRatio = 0
     	}
     })
    return pixelRatio
}

2. 初始化图表的时候设置像素比 devicePixelRatio API说明：echarts.init

   案例

//获取像素比
    const getPixelRatio = () => {
      let pixelRatio = 0
      wx.getSystemInfo({
        success: function (res) {
          pixelRatio = res.pixelRatio
        },
        fail: function () {
          pixelRatio = 0
        }
      })
      return pixelRatio
    }
    // console.log(pixelRatio)
    var dpr = getPixelRatio()
      // 初始化图表
    const chart = echarts.init(canvas, null, {
      // renderer: 'svg',//微信小程序中不支持该设置
      width: width,
      height: height,
      devicePixelRatio: dpr
    });
    setOption(chart,this);