【报Bug】uni-app ble接口在ios下无法监听到设备的特征值变化

详细问题描述

使用HBuildX构建uni-app，使用ble相关的接口，在微信小程序中可以顺利完成特征值的订阅和监听到特征值的变化，但是ios真机调试时，订阅特征值变化成功后会收到设备的一条数据（微信小程序不会），但是后续再也收不到特征值变化的通知。

[内容]

代码片段

  /**  
   * 订阅操作成功后需要设备主动更新特征值的 value，才会触发 uni.onBLECharacteristicValueChange 回调。  
   */  
  notifyBLECharacteristicValueChange() {  
    console.log('订阅消息')  
    uni.notifyBLECharacteristicValueChange({  
      state: true, // 启用 notify 功能  
      // 这里的 deviceId 需要已经通过 createBLEConnection 与对应设备建立链接  
      deviceId: this.deviceId,  
      // 这里的 serviceId 需要在 getBLEDeviceServices 接口中获取  
      serviceId: this.serviceId,  
      // 这里的 characteristicId 需要在 getBLEDeviceCharacteristics 接口中获取  
      characteristicId: this.notifyCharacteristicId,  
      success(res) {  
        console.log('notifyBLECharacteristicValueChange success:' + JSON.stringify(res));  
        console.log('onBLECharacteristicValueChange...')  
        uni.onBLECharacteristicValueChange(function (characteristic) {  
          console.log('监听低功耗蓝牙设备的特征值变化事件成功');  
          console.log(JSON.stringify(characteristic));  
          var ret = "";  
          let dataView = new DataView(characteristic.value);  
          for (var i = 0; i < characteristic.value.byteLength; i++) {  
            var value = dataView.getUint8(i).toString(16).toUpperCase();  
            if (value.length < 2) {  
              value = "0" + value;  
            }  
            ret = ret + value + " ";  
          }  
          var msg = ret.substr(0, ret.length - 1)  
          console.log("设备返回完整数据: " + msg);  
        });  
      }  
    });  
  }  

[步骤]

[结果]
IOS真机调试日志：（功能异常）
...
20:18:56.136 [LOG] : 订阅消息 at pages\test\index.vue:251
20:18:56.155 [LOG] : notifyBLECharacteristicValueChange success:{"errMsg":"notifyBLECharacteristicValueChange:ok"} at pages\test\index.vue:261
20:18:56.178 [LOG] : onBLECharacteristicValueChange... at pages\test\index.vue:262
20:18:56.197 [LOG] : 监听低功耗蓝牙设备的特征值变化事件成功 at pages\test\index.vue:264
20:18:56.217 [LOG] : {"deviceId":"A93B13A8-551C-12F9-EF79-12ECCFF926CB","serviceId":"00001900-0000-1000-8000-00805F9B34FB","characteristicId":"00001901-0000-1000-8000-00805F9B34FB","value":{}} at pages\test\index.vue:265
20:18:56.239 [LOG] : 设备返回完整数据: 03 00 03 00 03 00 03 01 00 00 00 00 00 00 00 00 02 00 04 03 05 03 05 01 03 00 02 00 03 02 03 00 02 00 03 00 00 00 00 00 00 00 00 00 04 00 04 00 00 00 00 00 00 00 at pages\test\index.vue:276
20:19:52.222 [LOG] : 要发送的消息: 30 30 30 31 at pages\test\index.vue:162
20:19:52.243 [LOG] : writeBLECharacteristicValue success{"errMsg":"writeBLECharacteristicValue:ok"} at pages\test\index.vue:64
=======================接收不到数据==============================

微信小程序日志（功能正常）
...
index.vue:251 订阅消息
index.vue:261 notifyBLECharacteristicValueChange success:{"errCode":"0","errMsg":"notifyBLECharacteristicValueChange:ok"}
index.vue:262 onBLECharacteristicValueChange...
index.vue:162 要发送的消息: 30 30 30 31
index.vue:64 writeBLECharacteristicValue success{"errCode":0,"errMsg":"writeBLECharacteristicValue:ok"}
index.vue:264 监听低功耗蓝牙设备的特征值变化事件成功
index.vue:265 {"deviceId":"A93B13A8-551C-12F9-EF79-12ECCFF926CB","serviceId":"00001900-0000-1000-8000-00805F9B34FB","characteristicId":"00001901-0000-1000-8000-00805F9B34FB","value":{}}
index.vue:276 设备返回完整数据: 30 30 30 31 0D 0A 0D 0A 2B 43 53 51 3A 20 32 30 2C 30 0D 0A 0D 0A 4F 4B 0D 0A 00

[期望]

[如果语言难以表述清晰，拍一个视频或截图，有图有真相]

IDE运行环境说明

[HBuilderX]

[IDE版本号]
1.9.3.20190422

[windows版本号]
10

[mac版本号]

uni-app运行环境说明

[运行端是h5或app或某个小程序？]

[运行端版本号]

[项目是cli创建的还是HBuilderX创建的？如果是cli创建的，请更新到最新版cli再试]

[编译模式是老模板模式还是新的自定义组件模式？]

App运行环境说明

[Android版本号]

[iOS版本号]
11.4

[手机型号]
ip 6s plus

[模拟器型号]

附件

[IDE问题请提供HBuilderX运行日志。菜单帮助-查看运行日志，点右键打开文件所在目录，将log文件压缩成zip包上传]