大家好，我是 React Native 的新手，在我的应用程序中，我试图扫描 ble 设备并在屏幕上列出它们的名称。在代码源中，人们最常将蓝牙低功耗管理器创建为 const manager = new BleManager(); ，但是当我尝试此代码（当然还有其他方法）时，它会出现类似这样的错误

TypeError: null is not an object (evaluating '_BleModule.BleModule.createClient')

This error is located at:
    in HelloWorldApp (created by ExpoRoot)
    in ExpoRoot
    in RCTView (created by View)
    in View (created by AppContainer)
    in RCTView (created by View)
    in View (created by AppContainer)
    in AppContainer
at node_modules\react-native\Libraries\LogBox\LogBox.js:149:8 in registerError
at node_modules\react-native\Libraries\LogBox\LogBox.js:60:8 in errorImpl
at node_modules\react-native\Libraries\LogBox\LogBox.js:34:4 in console.error
at node_modules\expo\build\environment\react-native-logs.fx.js:27:4 in error
at node_modules\react-native\Libraries\Core\ExceptionsManager.js:104:6 in reportException
at node_modules\react-native\Libraries\Core\ExceptionsManager.js:172:19 in handleException
at node_modules\react-native\Libraries\Core\ReactFiberErrorDialog.js:43:2 in showErrorDialog
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:15792:34 in logCapturedError        
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:15884:20 in update.callback
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:7199:2 in callCallback
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:7220:20 in commitUpdateQueue
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:16632:25 in commitLifeCycles        
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:19216:22 in commitLayoutEffects     
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:93:4 in invokeGuardedCallbackProd
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:318:2 in invokeGuardedCallback      
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:18952:29 in commitRootImpl
at node_modules\scheduler\cjs\scheduler.development.js:468:23 in unstable_runWithPriority
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:18791:17 in commitRoot
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:18192:12 in performSyncWorkOnRoot   
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:5911:33 in runWithPriority$argument_1
at node_modules\scheduler\cjs\scheduler.development.js:468:23 in unstable_runWithPriority
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:5906:23 in flushSyncCallbackQueueImpl
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:5893:28 in flushSyncCallbackQueue
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:17745:30 in scheduleUpdateOnFiber   
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:21484:23 in updateContainer
at node_modules\react-native\Libraries\Renderer\implementations\ReactNativeRenderer-dev.js:22144:17 in render
at node_modules\react-native\Libraries\ReactNative\renderApplication.js:58:4 in renderApplication
at node_modules\react-native\Libraries\ReactNative\AppRegistry.js:117:25 in runnables.appKey.run
at node_modules\react-native\Libraries\ReactNative\AppRegistry.js:202:4 in runApplication
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:414:4 in __callFunction
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:113:6 in __guard$argument_0
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:365:10 in __guard
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:112:4 in callFunctionReturnFlushedQueue

这是我尝试创建管理器的代码：

import { StatusBar } from 'expo-status-bar';
import React, { Component } from 'react';
import { StyleSheet, Text, View } from 'react-native';
import { BleManager } from 'react-native-ble-plx';

const HelloWorldApp = () => {
  const manager = new BleManager();

我无法解决我的错误在哪里。请问有人能帮我解决这个问题吗？

注意：我还使用 npm install --save react-native-ble-plx 命令安装了 ble-plx 包。

注意 2：我使用 expo 创建了我的项目。