为什么在安卓中生效在IOS中失败？

appId: process.env.APPID, // 必填，公众号的唯一标识
timestamp: timestamp, // 必填，生成签名的时间戳
nonceStr: nonceStr, // 必填，生成签名的随机串nonceStr
signature: createSignature(timestamp, nonceStr), // 必填，签名
jsApiList: ['getLocation', 'scanQRCode', 'closeWindow'] // 必填，需要使用的JS接口列表

scanQRCodeView() {
      var _this = this;
      //扫描二维码点击，调用扫码
      weChatReady().then(() => {
        scanQRCode()
          .then(res => {
            console.log(res, "扫码结果&&&&&&&&&");
            if (res.data.projectId && res.data.spaceId) {
              console.log("判断成功");
              let samaoMatch = {
                projectId: res.data.projectId,
                spaceId: res.data.spaceId
              };
              console.log(res.data.projectId, "res.data.projectId");
              console.log(this, "UUUUUUUUUUUUUUUUUUUU");
              console.log(_this, "PPPPPPPPPPPPPPPPPPP");
              _this.$emit("scanMathc", samaoMatch);
            } else {
              Toast("无效二维码");
              return; //都为空的话，是么都不做
            }
          })
          .catch(err => {
            Toast("扫码失败了");
            console.error(err);
          });
      });