HarmonyOS Ble蓝牙demo

Ble蓝牙相关资料可参考：

https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-bluetooth-ble-V5#blestartblescan

以及

https://gitee.com/openharmony/docs/tree/master/zh-cn/application-dev/connectivity/bluetooth

以下是一个相对完整的蓝牙通信ble的样例：

demo代码总共有4个页面。一个util

主页MainPage上：

import { ble } from '@kit.ConnectivityKit';
import { BusinessError } from '@kit.BasicServicesKit';

@Entry
@Component
struct Client {
  @State clientInstanceSwitch: boolean = false;
  @State scanSwitch: boolean = false;
  @State deviceFindSwitch: boolean = false;
  @State bleDevices: Array<ble.ScanResult> = []

  build() {
    Column({ space: 15 }) {
      Row() {
        Text('BLE扫描')
        Blank()
        Toggle({ type: ToggleType.Switch, isOn: this.scanSwitch })
          .onChange((isOn: boolean) => {
            if (isOn) {
              this.startScan()
            } else {
              this.stopScan()
            }
            console.info('ble server instanceSwitch status:' + isOn)
          })
      }
      .itemStyle()

      Column() {
        Row() {
          Text('订阅BLE设备')
          Blank()
          Toggle({ type: ToggleType.Switch, isOn: this.deviceFindSwitch })
            .onChange((isOn: boolean) => {
              if (isOn) {
                this.onBLEDeviceFind()
              } else {
                this.offBLEDeviceFind()
              }
              console.info('ble server instanceSwitch status:' + isOn)
            })
        }
        .itemStyle()
        .borderRadius({ topLeft: 10, topRight: 10 })

        Divider()
        Scroll() {
          if (this.bleDevices.length > 0) {
            List() {
              ForEach(this.bleDevices, (item: ble.ScanResult) => {
                ListItem() {
                  Navigator({ target: 'pages/ClientDetail', type: NavigationType.Push }) {
                    Text(item.deviceId)
                      .width('100%').textAlign(TextAlign.Start)
                  }
                  .params(item)
                }
              })
            }
          } else {
            Text('暂无设备发现')
          }
        }
        .itemStyle()
        .height(380)
        .borderRadius({ bottomLeft: 10, bottomRight: 10 })
        .scrollBar(BarState.Off)
      }
    }
    .height('100%')
    .width('100%')
    MainPage中：

    .padding({ left: 15, right: 15, top: 20, bottom: 20 })
      .backgroundColor($r('app.color.light_gray'))
  }

  /**
   * 发起BLE扫描流程
   */
  startScan() {
    try {
      let scanFilter: ble.ScanFilter = {
        serviceUuid: "00001810-0000-1000-8000-00805F9B34FB"
      };

      let scanOptions: ble.ScanOptions = {
        interval: 500,
        dutyMode: ble.ScanDuty.SCAN_MODE_LOW_POWER,
        matchMode: ble.MatchMode.MATCH_MODE_AGGRESSIVE,
      }
      ble.startBLEScan([scanFilter], scanOptions);
      console.info('ble Client start BLE Scan success')
      this.scanSwitch = true;
    } catch (err) {
      console.error('errCode: ' + (err as BusinessError).code + ', errMessage: ' + (err as BusinessError).message);
    }
  }

  /**
   * 关闭BLE扫描流程
   */
  stopScan() {
    try {
      ble.stopBLEScan();
      console.info('ble Client stop BLE Scan success')
      this.scanSwitch = false;
    } catch (err) {
      console.error('errCode: ' + (err as BusinessError).code + ', errMessage: ' + (err as BusinessError).message);
    }
  }

  /**
   * 取消订阅BLE设备发现
   */
  onBLEDeviceFind() {
    ble.on('BLEDeviceFind', (data: Array<ble.ScanResult>) => {
      console.info('bluetooth device find on = ' + JSON.stringify(data));
      this.bleDevices = data;
    });
    this.deviceFindSwitch = true;
  }
  MainPage下：

  /**
   * 取消订阅BLE设备发现
   */
  offBLEDeviceFind() {
    ble.off('BLEDeviceFind', (data: Array<ble.ScanResult>) => {
      console.info('bluetooth device find off = ' + JSON.stringify(data));
      // this.bleDevices = data;
    });
    this.deviceFindSwitch = false;
  }
}

@Styles
function itemStyle() {
  .width('100%')
  .padding({ left: 15, right: 15, top: 8, bottom: 8 })
  .backgroundColor($r('app.color.white'))
  .borderRadius(10)
}

上面发的是clinet页面

mainpage页面：

import { router } from '@kit.ArkUI'
import PermissionsUtil from '../utils/PermissionsUtil'

@Entry
@Component
struct MainPage {
  aboutToAppear(): void {
    PermissionsUtil.requestPermissions(['ohos.permission.ACCESS_BLUETOOTH'])
  }

  build() {
    Column() {
      Button('客户端').onClick((event: ClickEvent) => {
        router.pushUrl({ url: "pages/Client" })
      })
        .width('50%')

      Button('服务端').onClick((event: ClickEvent) => {
        router.pushUrl({ url: "pages/Server" })
      })
        .width('50%')
    }
    .height('100%')
    .width('100%')
    .justifyContent(FlexAlign.SpaceAround)
  }
}

ClientDetail页面代码：

import { ble, constant } from '@kit.ConnectivityKit';
import { router } from '@kit.ArkUI';
import { BusinessError } from '@kit.BasicServicesKit';

@Entry
@Component
struct ClientDetail {
  device: ble.ScanResult = router.getParams() as ble.ScanResult;
  @State gattClient: ble.GattClientDevice | undefined = undefined;
  @State deviceName: string = '';
  @State gattServiceInfo: ble.GattService | undefined = undefined;
  @State connectSwitch: boolean = false;
  @State stateListenSwitch: boolean = false;
  @State connectStateSwitch: boolean = false;
  @State bleCharChangeSwitch: boolean = false;
  @State connectState: ble.ProfileConnectionState = constant.ProfileConnectionState.STATE_DISCONNECTED;
  @State characteristicValue: string = '';
  private serviceUuid = "00001810-0000-1000-8000-00805F9B34FB";
  @State writeValue: string = ''

  aboutToAppear(): void {
    if (!this.gattClient) {
      this.gattClient = ble.createGattClientDevice(this.device?.deviceId);
      this.getDeviceName()
    }
  }

  build() {
    Scroll() {
      Column({ space: 10 }) {
        Text() {
          Span('设备名称： ')
          Span(this.deviceName)
        }
        .itemStyle()

        Row() {
          Text('连接状态监听')
          Blank()
          Toggle({ type: ToggleType.Switch, isOn: this.stateListenSwitch })
            .onChange((isOn: boolean) => {
              if (isOn) {
                this.onBLEConnectionStateChange()
              } else {
                this.offBLEConnectionStateChange()
              }
              console.info('ble server instanceSwitch status:' + isOn)
            })
        }
        .itemStyle()

        Row() {
          Text('连接状态')
          Blank()
          if (this.connectState == constant.ProfileConnectionState.STATE_CONNECTING) {
            LoadingProgress().height(15).width(15)
          } else {
            Toggle({ type: ToggleType.Switch, isOn: this.connectStateSwitch })
              .enabled(false)
          }
        }
        .itemStyle()

        Row() {
          Text('连接开关')
          Blank()
          Toggle({ type: ToggleType.Switch, isOn: this.connectSwitch })
            .onChange((isOn: boolean) => {
              if (isOn) {
                this.connectServer()
              } else {
                this.disconnectServer()
              }
              console.info('ble server instanceSwitch status:' + isOn)
            })
        }
        .itemStyle()

        Column({ space: 10 }) {
          Button('服务发现').onClick((event: ClickEvent) => {
            this.getServices()
          })

          Scroll() {
            if (this.gattServiceInfo) {
              Text(JSON.stringify(this.gattServiceInfo))
            } else {
              Text('暂无数据')
            }
          }
          .height(100)
          .scrollBar(BarState.Off)
        }
        .itemStyle()

        Column({ space: 10 }) {
          Button('client端读取蓝牙低功耗设备特定服务的特征值').onClick((event: ClickEvent) => {
            this.readCharacteristicValue()
          })
          Scroll() {
            if (this.characteristicValue) {
              Text(JSON.stringify(this.characteristicValue))
            } else {
              Text('暂无数据')
            }
          }
          .height(100)
          .scrollBar(BarState.Off)
        }
        .itemStyle()

        Button('写描述符').onClick((event: ClickEvent) => {
          this.writeDescriptorValue()