小程序canvas使用网络图片真机不显示解决方案----可直接使用案例测试

/*
 * author:咔咔
 * address:陕西西安
 * wechat:fangkangfk
 * */
// 小程序二维码
      var path1 = 'https://www.weiuid.com/attachs/uploads/20180913/6386.png';
      const ctx = wx.createCanvasContext('myCanvas')
      // // 封面图
      var path = 'https://www.weiuid.com/attachs/uploads/20180912/d70711527c3ca66054f9989af7975d87.jpg';
      wx.getImageInfo({
        src: path,//服务器返回的图片地址
        success: function (res) {
          //res.path是网络图片的本地地址
          let Path = res.path;
          ctx.drawImage(Path, 0, 0, 400, 200)
        },
        fail: function (res) {
          //失败回调
        }
      });
      var that = this;
      //获取网络图片本地路径
      wx.getImageInfo({
        src: path1,//服务器返回的图片地址
        success: function (res) {
          //res.path是网络图片的本地地址
          let Path = res.path;
          ctx.drawImage(Path, 140, 300, 100, 100)
          ctx.draw(false, function () {
            wx.canvasToTempFilePath({
              canvasId: 'myCanvas',
              success: function (res) {
                console.log(res.tempFilePath)
                wx.previewImage({
                  urls: [res.tempFilePath] // 需要预览的图片http链接列表
                })
              }
            })
          });
        },
        fail: function (res) {
          //失败回调
        }
      });