OpenHarmony 扫码自动配网-51CTO.COM

背景

随着移动互联网的发展,WiFi已成为人们生活中不可或缺的网络接入方式。但在连接WiFi时,用户常需要手动输入一个复杂的密钥,这带来了一定的不便。针对这一痛点,利用QR码连接WiFi的方案应运而生。QR码连接WiFi的工作流程是:商家或公共场所提供含有WiFi密钥的QR码,用户只需使用手机扫一扫即可读取密钥信息并连接WiFi,无需手动输入，这种连接方式大大简化了用户的操作。随着智能手机摄像头识别能力的提升,以及用户需求的引领,利用QR码连接WiFi的方式未来还将得到更广泛的应用,为用户提供更稳定便捷的上网体验。它利用了移动互联网时代的技术优势,解决了传统WiFi连接中的痛点,是一种值得推广的网络连接方式。

效果

页面截图

扫码页面

配网连接中	配网连接成功	配网连接失败

在线视频播放的地址

优势

使用QR码连接WiFi具有以下优势:

提高了连接成功率,避免因手动输入密钥错误导致的连接失败问题。
加快了连接速度,扫码相对于手动输入更高效方便。
提升了用户体验,无需记忆和输入复杂密钥,操作更人性化。
方便密钥分享和更改,通过更新QR码即可实现。
在一些需要频繁连接不同WiFi的场景下尤其便利,如酒店、餐厅、机场等。
一些App可以自动识别WiFi二维码,实现零点击连接。

开发与实现

开发环境

开发平台：windows10、DevEco Studio 3.1 Release
系统：OpenHarmony 3.2 Release，API9(Full SDK 3.2.11.9)
设备：SD100（工业平板设备、平台：RK3568、屏幕像素：1920 * 1200）

项目开发

需求分析

支持相机扫码，并可以解析二维码信息。
获取二维码中的wifi连接信息，自动完成网络连接。
网络连接成功，则提示用户成功。
网络连接失败，则提示用户失败，可以重新连接。
UI界面符合OpenHarmony设计原则，应用界面简洁高效、自然流畅。

项目流程图

界面

说明：从需求上分析，可以有两个界面，一是扫码界面、二是wifi连接等待和显示结果界面。

详细开发

一、创建项目

说明：通过DevEco Studio创建一个OpenHarmony的项目。

二、申请权限

说明：在应用中涉及到使用相机和wifi的操作，需要动态申请一些必要的权限，我们可以在 EntryAbility.ts中实现，EntryAbility.ts继承UIAbility，用于管理应用的生面周期，在OnCreate是实例冷启动时触发，在此函数中实现权限申请。具体代码如下：

let permissionList: Array<Permissions> = [
  "ohos.permission.GET_WIFI_INFO",
  "ohos.permission.INTERNET",
  'ohos.permission.CAMERA',
  'ohos.permission.READ_MEDIA',
  'ohos.permission.WRITE_MEDIA',
  'ohos.permission.MEDIA_LOCATION',
  'ohos.permission.LOCATION',
  'ohos.permission.APPROXIMATELY_LOCATION'
]

onCreate(want, launchParam) {
  hilog.info(0x0000, 'testTag', '%{public}s', 'Ability onCreate');
  this.requestPermissions()
}

private requestPermissions() {
  let AtManager = abilityAccessCtrl.createAtManager()
  AtManager.requestPermissionsFromUser(this.context, permissionList).then(async (data) => {
    Logger.info(`${TAG} data permissions: ${JSON.stringify(data.permissions)}`)
    Logger.info(`${TAG} data authResult: ${JSON.stringify(data.authResults)}`)
    // 判断授权是否完成
    let resultCount: number = 0
    for (let result of data.authResults) {
      if (result === 0) {
        resultCount += 1
      }
    }
    let permissionResult : boolean = false
    if (resultCount === permissionList.length) {
      permissionResult = true
    }
    AppStorage.SetOrCreate(KEY_IS_PERMISSION, true)
    this.sendPermissionResult(permissionResult)
  })
}

sendPermissionResult(result : boolean) {
  let eventData: emitter.EventData = {
    data: {
      "result": result
    }
  };

  let innerEvent: emitter.InnerEvent = {
    eventId: EVENT_PERMISSION_ID,
    priority: emitter.EventPriority.HIGH
  };

  emitter.emit(innerEvent, eventData);
  Logger.info(`${TAG} sendPermissionResult`)
}

onDestroy() {
  Logger.info(`${TAG} onDestroy`)
  emitter.off(EVENT_PERMISSION_ID)
}

代码解析：

在应用中使用到相机和操作wifi需要根据需要动态申请相关权限，具体的权限用途可以查看：应用权限列表。
应用动态授权需要使用到@ohos.abilityAccessCtrl (程序访问控制管理)，通过abilityAccessCtrl.createAtManager()获取到访问控制对象 AtManager。
通过AtManager.requestPermissionsFromUser() 拉起请求用户授权弹窗，由用户动态授权。
授权成功后通过Emitter（@ohos.events.emitter）向主界面发送授权结果。
在onDestroy()应用退出函数中取消Emitter事件订阅。

三、首页

说明：首页即为扫码页面，用于识别二维码获取二维码信息，为网络连接准备。所以此页面有有个功能，加载相机和识别二维码。

媒体相机：

相机的启动借鉴社区提供的代码案例：二维码扫码。

相机功能在CameraServices中，源码参考CameraServices.ets。

获取相机实例使用到媒体相机接口@ohos.multimedia.camera (相机管理)。
首先使用camera.getCameraManager方法获取相机管理器，然后使用cameraManager.getSupportedCameras方法得到设备列表, 这里默认点亮列表中的首个相机；
打开相机：使用 cameraManager.createCameraInput方法创建CameraInput实例，调用open方法打开相机；
获取相机输出流：使用getSupportedOutputCapability查询相机设备在模式下支持的输出能力，然后使用createPreviewOutput创建相机输出流。
获取拍照输出流，使用@ohos.multimedia.image接口的 createImageReceiver 方法创建ImageReceiver实例，并通过其getReceivingS_urfaceId()获取S_urfaceId，通过CameraManager.createPhotoOutput()函数构建拍照输出流，并将imageReceive 的 S_urfaceId与其建立绑定关系。
获取相片输出：首先使用createCaptureSession方法创建捕获会话的实例，然后使用beginConfig方法配置会话，接下来使用addInput方法添加一个摄像头输入流，使用addOutput添加一个摄像头和相机照片的输出流，使用commitConfig方法提交会话配置后，调用会话的start方法开始捕获相片输出。
这里也可以使用相机预览流获取图像数据，但在界面上需要预览，所以这里需要构建两条预览流，一条预览流用于显示，在XComponent组件中渲染，另外一条预览流用于获取头像数据用于解析，根据实践发现，开启两条预览流后，相机帧率为：7fsp，表现为预览卡顿，所以为提升预览效果，使用定时拍照的方式获取图像数据。
获取图像的在SaveCameraAsset.ets中实现，扫码页面启动后每间隔1.5s调用PhotoOutput.capture()实现拍照，通过imageReceiver.on(‘imageArrival’)接收图片，使用imageReceiver.readNextImage()获取图像对象，通过Image.getComponent()获取图像缓存数据。

具体实现代码：

CameraService：

import camera from '@ohos.multimedia.camera';
import image from '@ohos.multimedia.image';
import SaveCameraAsset from './SaveCameraAsset'
import { QRCodeScanConst, SCAN_TYPE } from './QRCodeScanConst'
import { Logger } from '@ohos/common'
import common from '@ohos.app.ability.common'
let TAG: string = 'CameraService'
/**
 * 拍照保存图片回调
 */
export interface FunctionCallBack {
  onCaptureSuccess(thumbnail: image.PixelMap, resourceUri: string): void
  onCaptureFailure(): void
  onRecordSuccess(thumbnail: image.PixelMap): void
  onRecordFailure(): void
  /**
   * 缩略图
   */
  thumbnail(thumbnail: image.PixelMap): void
  /**
   * AI 识别结果
   * @param result 识别结果
   */
  aiResult(result: string): void
}
export interface PreviewCallBack {
  onFrameStart()
  onFrameEnd()
}
export interface MetaDataCallBack {
  onRect(rect: camera.Rect)
}
export default class CameraService {
  private static instance: CameraService = null
  private mCameraManager: camera.CameraManager = null
  private mCameraCount: number = 0 // 相机总数
  private mCameraMap: Map<string, Array<camera.CameraDevice>> = new Map()
  private mCurCameraDevice: camera.CameraDevice = null
  private mCameraInput: camera.CameraInput = null
  private mPreviewOutput: camera.PreviewOutput = null
  private mPreviewOutputByImage: camera.PreviewOutput = null
  private mPhotoOutput: camera.PhotoOutput = null
  private mSaveCameraAsset: SaveCameraAsset = new SaveCameraAsset()
  private mCaptureSession: camera.CaptureSession
  private mMetadataOutput: camera.MetadataOutput
  private constructor() {
  }
  /**
   * 单例
   */
  public static getInstance(): CameraService {
    if (this.instance === null) {
      this.instance = new CameraService()
    }
    return this.instance
  }
  /**
   * 初始化
   */
  public async initCamera(): Promise<number> {
    Logger.info(`${TAG} initCamera`)
    if (this.mCameraManager === null) {
      this.mCameraManager = camera.getCameraManager(AppStorage.Get('context'))
      // 注册监听相机状态变化
      this.mCameraManager.on('cameraStatus', (cameraStatusInfo) => {
        Logger.info(`${TAG} camera Status: ${JSON.stringify(cameraStatusInfo)}`)
      })
      // 获取相机列表
      let cameras: Array<camera.CameraDevice> = this.mCameraManager.getSupportedCameras()
      if (cameras) {
        this.mCameraCount = cameras.length
        Logger.info(`${TAG} mCameraCount: ${this.mCameraCount}`)
        if (this.mCameraCount === 0) {
          return this.mCameraCount
        }
        for (let i = 0; i < cameras.length; i++) {
          Logger.info(`${TAG} --------------Camera Info-------------`)
          const tempCameraId: string = cameras[i].cameraId
          Logger.info(`${TAG} camera_id: ${tempCameraId}`)
          Logger.info(`${TAG} cameraPosition: ${cameras[i].cameraPosition}`)
          Logger.info(`${TAG} cameraType: ${cameras[i].cameraType}`)
          const connectionType = cameras[i].connectionType
          Logger.info(`${TAG} connectionType: ${connectionType}`)
          // 判断本地相机还是远程相机
          if (connectionType === camera.ConnectionType.CAMERA_CONNECTION_BUILT_IN) {
            // 本地相机
            this.displayCameraDevice(QRCodeScanConst.LOCAL_DEVICE_ID, cameras[i])
          } else if (connectionType === camera.ConnectionType.CAMERA_CONNECTION_REMOTE) {
            // 远程相机 相机ID格式 ： deviceID__Camera_cameraID 例如：3c8e510a1d0807ea51c2e893029a30816ed940bf848754749f427724e846fab7__Camera_lcam001
            const cameraKey: string = tempCameraId.split('__Camera_')[0]
            Logger.info(`${TAG} cameraKey: ${cameraKey}`)
            this.displayCameraDevice(cameraKey, cameras[i])
          }
        }
        // todo test 选择首个相机
        this.mCurCameraDevice = cameras[0]
        Logger.info(`${TAG} mCurCameraDevice: ${this.mCurCameraDevice.cameraId}`)
      }
    }
    return this.mCameraCount
  }
  /**
   * 处理相机设备
   * @param key
   * @param cameraDevice
   */
  private displayCameraDevice(key: string, cameraDevice: camera.CameraDevice) {
    Logger.info(`${TAG} displayCameraDevice ${key}`)
    if (this.mCameraMap.has(key) && this.mCameraMap.get(key)?.length > 0) {
      Logger.info(`${TAG} displayCameraDevice has mCameraMap`)
      // 判断相机列表中是否已经存在此相机
      let isExist: boolean = false
      for (let item of this.mCameraMap.get(key)) {
        if (item.cameraId === cameraDevice.cameraId) {
          isExist = true
          break
        }
      }
      // 添加列表中没有的相机
      if (!isExist) {
        Logger.info(`${TAG} displayCameraDevice not exist , push ${cameraDevice.cameraId}`)
        this.mCameraMap.get(key).push(cameraDevice)
      } else {
        Logger.info(`${TAG} displayCameraDevice has existed`)
      }
    } else {
      let cameras: Array<camera.CameraDevice> = []
      Logger.info(`${TAG} displayCameraDevice push ${cameraDevice.cameraId}`)
      cameras.push(cameraDevice)
      this.mCameraMap.set(key, cameras)
    }
  }
  /**
   * 创建相机输入流
   * @param cameraIndex 相机下标
   * @param deviceId 设备ID
   */
  public async createCameraInput(cameraIndex?: number, deviceId?: string) {
    Logger.info(`${TAG} createCameraInput`)
    if (this.mCameraManager === null) {
      Logger.error(`${TAG} mCameraManager is null`)
      return
    }
    if (this.mCameraCount <= 0) {
      Logger.error(`${TAG} not camera device`)
      return
    }
    if (this.mCameraInput) {
      this.mCameraInput.close()
    }
    if (deviceId && this.mCameraMap.has(deviceId)) {
      if (cameraIndex < this.mCameraMap.get(deviceId)?.length) {
        this.mCurCameraDevice = this.mCameraMap.get(deviceId)[cameraIndex]
      } else {
        this.mCurCameraDevice = this.mCameraMap.get(deviceId)[0]
      }
    }
    Logger.info(`${TAG} mCurCameraDevice: ${this.mCurCameraDevice?.cameraId}`)
    try {
      this.mCameraInput = this.mCameraManager.createCameraInput(this.mCurCameraDevice)
      Logger.info(`${TAG} mCameraInput: ${JSON.stringify(this.mCameraInput)}`)
      this.mCameraInput.on('error', this.mCurCameraDevice, (error) => {
        Logger.error(`${TAG} CameraInput error: ${JSON.stringify(error)}`)
      })
      await this.mCameraInput.open()
    } catch (err) {
      if (err) {
        Logger.error(`${TAG} failed to createCameraInput`)
      }
    }
  }
  /**
   * 释放相机输入流
   */
  public async releaseCameraInput() {
    Logger.info(`${TAG} releaseCameraInput`)
    if (this.mCameraInput) {
      try {
        await this.mCameraInput.close()
        Logger.info(`${TAG} releaseCameraInput closed`)
      } catch (err) {
        Logger.error(`${TAG} releaseCameraInput ${err}}`)
      }
      this.mCameraInput = null
    }
  }

  /**
   * 创建相机预览输出流
   */
  public async createPreviewOutput(s_urfaceId: string, callback?: PreviewCallBack) {
    Logger.info(`${TAG} createPreviewOutput s_urfaceId ${s_urfaceId}`)
    if (this.mCameraManager === null) {
      Logger.error(`${TAG} createPreviewOutput mCameraManager is null`)
      return
    }
    // 获取当前相机设备支持的输出能力
    let cameraOutputCap = this.mCameraManager.getSupportedOutputCapability(this.mCurCameraDevice)
    if (!cameraOutputCap) {
      Logger.error(`${TAG} createPreviewOutput getSupportedOutputCapability error}`)
      return
    }
    Logger.info(`${TAG} createPreviewOutput cameraOutputCap ${JSON.stringify(cameraOutputCap)}`)
    let previewProfilesArray = cameraOutputCap.previewProfiles
    let previewProfiles: camera.Profile
    if (!previewProfilesArray || previewProfilesArray.length <= 0) {
      Logger.error(`${TAG} createPreviewOutput previewProfilesArray error}`)
      previewProfiles = {
        format: 1,
        size: {
          width: QRCodeScanConst.DEFAULT_WIDTH,
          height: QRCodeScanConst.DEFAULT_HEIGHT
        }
      }
    } else {
      Logger.info(`${TAG} createPreviewOutput previewProfile length ${previewProfilesArray.length}`)
      previewProfiles = previewProfilesArray[0]
    }
    Logger.info(`${TAG} createPreviewOutput previewProfile[0] ${JSON.stringify(previewProfiles)}`)
    try {
      this.mPreviewOutput = this.mCameraManager.createPreviewOutput(previewProfiles, s_urfaceId)
      Logger.info(`${TAG} createPreviewOutput success`)
      // 监听预览帧开始
      this.mPreviewOutput.on('frameStart', () => {
        Logger.info(`${TAG} createPreviewOutput camera frame Start`)
        if (callback) {
          callback.onFrameStart()
        }
      })
      this.mPreviewOutput.on('frameEnd', () => {
        Logger.info(`${TAG} createPreviewOutput camera frame End`)
        if (callback) {
          callback.onFrameEnd()
        }
      })
      this.mPreviewOutput.on('error', (error) => {
        Logger.error(`${TAG} createPreviewOutput error: ${error}`)
      })
    } catch (err) {
      Logger.error(`${TAG} failed to createPreviewOutput ${err}`)
    }
  }
  /**
   *  释放预览输出流
   */
  public async releasePreviewOutput() {
    Logger.info(`${TAG} releaseCamera PreviewOutput`)
    if (this.mPreviewOutput) {
      await this.mPreviewOutput.release()
      Logger.info(`${TAG} releaseCamera PreviewOutput release`)
      this.mPreviewOutput = null
    }
  }
  /**
   * 创建拍照输出流
   */
  public async createPhotoOutput(functionCallback: FunctionCallBack) {
    Logger.info(`${TAG} createPhotoOutput`)
    if (!this.mCameraManager) {
      Logger.error(`${TAG} createPhotoOutput mCameraManager is null`)
      return
    }
    // 通过宽、高、图片格式、容量创建ImageReceiver实例
    const receiver: image.ImageReceiver = image.createImageReceiver(QRCodeScanConst.DEFAULT_WIDTH, QRCodeScanConst.DEFAULT_HEIGHT, image.ImageFormat.JPEG, 8)
    const imageS_urfaceId: string = await receiver.getReceivingS_urfaceId()
    Logger.info(`${TAG} createPhotoOutput imageS_urfaceId: ${imageS_urfaceId}`)
    let cameraOutputCap = this.mCameraManager.getSupportedOutputCapability(this.mCurCameraDevice)
    Logger.info(`${TAG} createPhotoOutput cameraOutputCap ${cameraOutputCap}`)
    if (!cameraOutputCap) {
      Logger.error(`${TAG} createPhotoOutput getSupportedOutputCapability error}`)
      return
    }
    let photoProfilesArray = cameraOutputCap.photoProfiles
    let photoProfiles: camera.Profile
    if (!photoProfilesArray || photoProfilesArray.length <= 0) {
      // 使用自定义的配置
      photoProfiles = {
        format: camera.CameraFormat.CAMERA_FORMAT_JPEG,
        size: {
          width: QRCodeScanConst.DEFAULT_WIDTH,
          height: QRCodeScanConst.DEFAULT_HEIGHT
        }
      }
    } else {
      Logger.info(`${TAG} createPhotoOutput photoProfile length ${photoProfilesArray.length}`)
      photoProfiles = photoProfilesArray[0]
    }
    Logger.info(`${TAG} createPhotoOutput photoProfile ${JSON.stringify(photoProfiles)}`)
    try {
      this.mPhotoOutput = this.mCameraManager.createPhotoOutput(photoProfiles, imageS_urfaceId)
      Logger.info(`${TAG} createPhotoOutput mPhotoOutput success`)
      // 保存图片
      this.mSaveCameraAsset.saveImage(receiver, functionCallback)
    } catch (err) {
      Logger.error(`${TAG} createPhotoOutput failed to createPhotoOutput ${err}`)
    }
  }
  /**
   * 释放拍照输出流
   */
  public async releasePhotoOutput() {
    Logger.info(`${TAG} releaseCamera PhotoOutput`)
    if (this.mPhotoOutput) {
      await this.mPhotoOutput.release()
      Logger.info(`${TAG} releaseCamera PhotoOutput release`)
      this.mPhotoOutput = null
    }
  }
  public async createSession() {
    Logger.info(`${TAG} createSession`)
    this.mCaptureSession = await this.mCameraManager.createCaptureSession()
    Logger.info(`${TAG} createSession mCaptureSession ${this.mCaptureSession}`)
    this.mCaptureSession.on('error', (error) => {
      Logger.error(`${TAG} CaptureSession error ${JSON.stringify(error)}`)
    })
    try {
      this.mCaptureSession?.beginConfig()
      this.mCaptureSession?.addInput(this.mCameraInput)

      if (this.mPreviewOutputByImage != null) {
        Logger.info(`${TAG} createSession addOutput PreviewOutputByImage`)
        this.mCaptureSession?.addOutput(this.mPreviewOutputByImage)
      }

      if (this.mPreviewOutput != null) {
        Logger.info(`${TAG} createSession addOutput PreviewOutput`)
        this.mCaptureSession?.addOutput(this.mPreviewOutput)
      }
      if (this.mPhotoOutput != null) {
        Logger.info(`${TAG} createSession addOutput PhotoOutput`)
        this.mCaptureSession?.addOutput(this.mPhotoOutput)
      }
      if (this.mMetadataOutput != null) {
        Logger.info(`${TAG} createSession addOutput mMetadataOutput`)
        this.mCaptureSession?.addOutput(this.mMetadataOutput)
      }
    } catch (err) {
      if (err) {
        Logger.error(`${TAG} createSession beginConfig fail err:${JSON.stringify(err)}`)
      }
    }
    try {
      await this.mCaptureSession?.commitConfig()
    } catch (err) {
      if (err) {
        Logger.error(`${TAG} createSession commitConfig fail err:${JSON.stringify(err)}`)
      }
    }
    try {
      await this.mCaptureSession?.start()
    } catch (err) {
      if (err) {
        Logger.error(`${TAG} createSession start fail err:${JSON.stringify(err)}`)
      }
    }
    if (this.mMetadataOutput) {
      this.mMetadataOutput.start().then(() => {
        Logger.info(`${TAG} Callback returned with metadataOutput started`)
      }).catch((err) => {
        Logger.error(`${TAG} Failed to metadataOutput start ${err.code}`)
      })
    }
    Logger.info(`${TAG} createSession mCaptureSession start`)
  }
  public async releaseSession() {
    Logger.info(`${TAG} releaseCamera Session`)
    if (this.mCaptureSession) {
      await this.mCaptureSession.release()
      Logger.info(`${TAG} releaseCamera Session release`)
      this.mCaptureSession = null
    }
  }
  /**
   * 拍照
   */
  public async takePicture() {
    Logger.info(`${TAG} takePicture`)
    if (!this.mCaptureSession) {
      Logger.info(`${TAG} takePicture session is release`)
      return
    }
    if (!this.mPhotoOutput) {
      Logger.info(`${TAG} takePicture mPhotoOutput is null`)
      return
    }
    try {
      const photoCaptureSetting: camera.PhotoCaptureSetting = {
        quality: camera.QualityLevel.QUALITY_LEVEL_HIGH,
        rotation: camera.ImageRotation.ROTATION_0,
        location: {
          latitude: 0,
          longitude: 0,
          altitude: 0
        },
        mirror: false
      }
      await this.mPhotoOutput.capture(photoCaptureSetting)
    } catch (err) {
      Logger.error(`${TAG} takePicture err:${JSON.stringify(err)}`)
    }
  }
  /**
   * 获取设备的相机列表
   * @param deviceId 设备ID
   */
  public getDeviceCameras(deviceId: string): Array<camera.CameraDevice> {
    Logger.info(`${TAG} getDeviceCameras ${deviceId} size ${this.mCameraMap.size}`)
    return this.mCameraMap.get(deviceId)
  }
  public getCameraCount(): number {
    return this.mCameraCount
  }
  /**
   * 释放相机
   */
  public async releaseCamera(): Promise<boolean> {
    Logger.info(`${TAG} releaseCamera`)
    let result: boolean = false
    let tempStartTime: number = new Date().getTime()
    try {
      await this.releaseCameraInput()
      await this.releasePhotoOutput()
      await this.releasePreviewOutput()
      await this.releaseSession()
      result = true
    } catch (err) {
      Logger.error(`${TAG} releaseCamera fail ${JSON.stringify(err)}`)
    }
    let tempTime: number = new Date().getTime() - tempStartTime
    Logger.info(`${TAG} releaseCamera finish time: ${tempTime}`)
    return result
  }
  public async selectPic() {
    Logger.info("getSingleImageFromAlbum start")
    let context = AppStorage.Get('context') as common.UIAbilityContext
    let abilityResult = await context.startAbilityForResult({
      bundleName: 'com.ohos.photos',
      abilityName: 'com.ohos.photos.MainAbility',
      parameters: {
        uri: 'singleselect' // 只选取单个文件
      }
    })
    if (abilityResult.want === null || abilityResult.want === undefined) {
      Logger.info("getSingleImageFromAlbum end. abilityResult.want is null.")
      return null
    }
    if (abilityResult.want.parameters === null || abilityResult.want.parameters === undefined) {
      Logger.info("getSingleImageFromAlbum end. abilityResult.want.parameters is null.")
      return null
    }
    let images = abilityResult.want.parameters['select-item-list']
    let imageUri = images[0]
    Logger.info("getSingleImageFromAlbum end. uri:" + imageUri)
    return imageUri
  }
}

SaveCameraAsset：

import image from '@ohos.multimedia.image'
import { FunctionCallBack } from './CameraService'
import { Logger } from '@ohos/common'
import CodeRuleUtil from '../utils/CodeRuleUtil'


const TAG: string = 'SaveCameraAsset'

/**
 * 保存相机拍照的资源
 */
export default class SaveCameraAsset {
  constructor() {

  }

  /**
   *  保存拍照图片
   * @param imageReceiver 图像接收对象
   * @param thumbWidth 宽度
   * @param thumbHeight 高度
   * @param callback 回调
   */
  public saveImage(imageReceiver: image.ImageReceiver, callback: FunctionCallBack) {
    console.info(`${TAG} saveImage`)
    let buffer = new ArrayBuffer(4096)
    const imgWidth: number = imageReceiver.size.width
    const imgHeight: number = imageReceiver.size.height
    Logger.info(`${TAG} saveImage size ${JSON.stringify(imageReceiver.size)}`)
    // 接收图片回调
    imageReceiver.on('imageArrival', async () => {
      console.info(`${TAG} saveImage ImageArrival`)
      // 使用当前时间命名
      imageReceiver.readNextImage((err, imageObj: image.Image) => {
        if (imageObj === undefined) {
          Logger.error(`${TAG} saveImage failed to get valid image error = ${err}`)
          return
        }
        // 根据图像的组件类型从图像中获取组件缓存 4-JPEG类型
        imageObj.getComponent(image.ComponentType.JPEG, async (errMsg, imgComponent) => {
          if (imgComponent === undefined) {
            Logger.error(`${TAG} getComponent failed to get valid buffer error = ${errMsg}`)
            return
          }
          if (imgComponent.byteBuffer) {
            Logger.info(`${TAG} getComponent imgComponent.byteBuffer ${imgComponent.byteBuffer.byteLength}`)
            buffer = imgComponent.byteBuffer
            // todo 内置解码库不开源
            let resultRGB: string = qr.decode(buffer)
            Logger.info(`${TAG} AI uimg result RGB ${resultRGB}`)
            if (callback) {
              callback.aiResult(CodeRuleUtil.getRuleResult(resultRGB))
            }
          } else {
            Logger.info(`${TAG} getComponent imgComponent.byteBuffer is undefined`)
          }

解码：

说明：解码使用内部的解码库因为不开源，非常抱歉，当然可以使用开源解码可以，如jsqr、zxing。

"dependencies": {
    "jsqr": "^1.4.0",
    "@ohos/zxing": "^2.0.0"
  }

四、配网协议

说明：处于通用性考虑，需要对配网的二维码解析约定一个协议，也就是约定联网二维码数据的格式：##ssid##pwd##securityType

ssid ：热点的SSID，编码格式为UTF-8。
pwd ：热点的密钥。
securityType ：加密类型，这可以参看wifiManager.WifiSecurityType。

在项目中也提供了协议解析类AnalyticResult.ts，具体代码如下：

/**
 * 结果解析类
 */
export type ResultType = {
  ssid: string,
  pwd: string,
  securityType : number
}

const SEPARATOR: string = '##'

export class Analytic {
  constructor() {

  }

  getResult(msg: string): ResultType {
    let result: ResultType = null
    if (msg && msg.length > 0 && msg.indexOf(SEPARATOR) >= 0) {
      let resultArr: string[] = msg.split(SEPARATOR)
      if (resultArr.length >= 4) {
        result = {
          ssid: resultArr[1],
          pwd: resultArr[2],
          securityType: parseInt(resultArr[3])
        }
      }
    }
    return result
  }
}

五、配网页面

说明：通过对配网二维码的解析获取到热点的ssid、密钥、加密类型，就可以通过@ohos.wifiManager(WLAN)提供的网络连接接口实现配网。因为网络连接需要调用系统的一些验证流程，需要消耗一些时间，为了优化交互，需要一个网络连接等待界面ConnectPage.ets，界面截图如下：

具体代码如下：

import { WifiConnectStatus } from '../model/Constant'
import router from '@ohos.router';
import { Logger } from '@ohos/common'
import wifi from '@ohos.wifiManager';
import { ResultType } from '../model/AnalyticResult'
import { WifiModel } from '../model/WifiModel'
/**
 * 网络连接页面
 */
const TAG: string = '[ConnectPage]'
const MAX_TIME_OUT: number = 60000 // 最大超时时间
@Entry
@Component
struct ConnectPage {
  @State mConnectSsid: string = ''
  @State mConnectStatus: WifiConnectStatus = WifiConnectStatus.CONNECTING
  @State mConnectingAngle : number = 0
  @State mConnectFailResource : Resource = $r('app.string.connect_wifi_fail')
  private linkedInfo: wifi.WifiLinkedInfo = null
  private mWifiModel: WifiModel = new WifiModel()
  private mTimeOutId: number = -1
  private mAnimationTimeOutId : number = -1
  async aboutToAppear() {
    Logger.info(`${TAG} aboutToAppear`)
    this.showConnecting()
    let wifiResult: ResultType = router.getParams()['wifiResult']
    Logger.info(`${TAG} wifiResult : ${JSON.stringify(wifiResult)}`)
    // 如果wifi是开的，就记录下状态，然后扫描wifi，并获取连接信息
    if (!wifi.isWifiActive()) {
      Logger.info(TAG, 'enableWifi')
      try {
        wifi.enableWifi()
      } catch (error) {
        Logger.error(`${TAG} wifi enable fail, ${JSON.stringify(error)}`)
      }
    }
    await this.getLinkedInfo()
    // 启动监听
    this.addListener()
    if (wifiResult == null) {
      Logger.info(TAG, 'wifiResult is null')
      this.mConnectFailResource = $r('app.string.scan_code_data_error')
      this.mConnectStatus = WifiConnectStatus.FAIL
    } else {
      this.mConnectSsid = wifiResult.ssid
      Logger.info(`${TAG} connect wifi ${this.mConnectSsid}`)
      this.disposeWifiConnect(wifiResult)
    }
  }
  /**
   * 启动超时任务
   */
  startTimeOut(): void {
    Logger.info(TAG, `startTimeOut`)
    this.mTimeOutId = setTimeout(() => {
      // 如果超过1分钟没有连接上网络，则认为网络连接超时
      try {
        this.mConnectFailResource = $r('app.string.connect_wifi_fail')
        this.mConnectStatus = WifiConnectStatus.FAIL
        wifi.disconnect();
      } catch (error) {
        Logger.error(TAG, `failed,code:${JSON.stringify(error.code)},message:${JSON.stringify(error.message)}`)
      }
    }, MAX_TIME_OUT)
  }
  /**
   * 取消超时任务
   */
  cancelTimeOut() {
    Logger.info(TAG, `cancelTimeOut id:${this.mTimeOutId}`)
    if (this.mTimeOutId >= 0) {
      clearTimeout(this.mTimeOutId)
      this.mTimeOutId = -1
    }
  }
  // 监听wifi的变化
  addListener() {
    // 连接状态改变时，修改连接信息
    wifi.on('wifiConnectionChange', async state => {
      Logger.info(TAG, `wifiConnectionChange: ${state}`)
      // 判断网络是否连接 0=断开  1=连接
      if (state === 1) {
        this.mConnectStatus = WifiConnectStatus.SUCCESS
        this.cancelTimeOut()
      }
      await this.getLinkedInfo()
    })
    // wifi状态改变时，先清空wifi列表，然后判断是否是开启状态，如果是就扫描
    wifi.on('wifiStateChange', state => {
      Logger.info(TAG, `wifiStateLisener state: ${state}`)
    })
  }
  // 获取有关Wi-Fi连接的信息,存入linkedInfo
  async getLinkedInfo() {
    try {
      let wifiLinkedInfo = await wifi.getLinkedInfo()
      if (wifiLinkedInfo === null || wifiLinkedInfo.bssid === '') {
        this.linkedInfo = null
        return
      }
      this.linkedInfo = wifiLinkedInfo
    } catch (err) {
      Logger.info(`getLinkedInfo failed err is ${JSON.stringify(err)}`)
    }
  }
  /**
   * 处理wifi连接
   * @param wifiResult
   */
  disposeWifiConnect(wifiResult: ResultType): void {
    this.mConnectStatus = WifiConnectStatus.CONNECTING
    if (this.linkedInfo) {
      // 说明wifi已经连接，需要确认需要连接的wifi和已连接的wifi是否为相同
      let linkedSsid: string = this.linkedInfo.ssid;
      if (linkedSsid === wifiResult.ssid) {
        Logger.info(`${TAG} The same ssid`);
        this.mConnectStatus = WifiConnectStatus.SUCCESS
        return;
      }
      // 如果wifi不同，则先断开网络连接，再重新连接
      try {
        wifi.disconnect();
        this.connectWifi(wifiResult.ssid, wifiResult.pwd, wifiResult.securityType)
      } catch (error) {
        Logger.error(TAG, `failed,code:${JSON.stringify(error.code)},message:${JSON.stringify(error.message)}`)
      }
    } else {
      this.connectWifi(wifiResult.ssid, wifiResult.pwd, wifiResult.securityType)
    }
  }
  private connectWifi(ssid: string, pwd: string, securityType : number) {
    this.startTimeOut()
    this.mWifiModel.connectNetwork(ssid, pwd, securityType)
  }
  async gotoIndex() {
    try {
      let options: router.RouterOptions = {
        url: "pages/Index"
      }
      await router.replaceUrl(options)
    } catch (error) {
      Logger.error(`${TAG} go to index fail, err: ${JSON.stringify(error)}`)
    }
  }
  showConnecting() {
    this.mConnectingAngle = 0
    this.mAnimationTimeOutId = setTimeout(() => {
      this.mConnectingAngle = 360
    }, 500)
  }
  closeConnecting() {
    if (this.mAnimationTimeOutId > -1) {
      clearTimeout(this.mAnimationTimeOutId)
    }
  }
  aboutToDisappear() {
    wifi.off('wifiConnectionChange')
    wifi.off('wifiStateChange')
    this.cancelTimeOut()
    this.closeConnecting()
  }
  build() {
    Column() {
      // back
      Row() {
        Image($r('app.media.icon_back'))
          .width(30)
          .height(30)
          .objectFit(ImageFit.Contain)
          .onClick(() => {
            router.back()
          })
      }
      .width('90%')
      .height('10%')
      .justifyContent(FlexAlign.Start)
      .alignItems(VerticalAlign.Center)
      Stack() {
        // 背景
        Column() {
          Image($r('app.media.bg_connect_wifi'))
            .width('100%')
            .height('100%')
            .objectFit(ImageFit.Contain)
            .rotate({
              x: 0,
              y: 0,
              z: 1,
              centerX: '50%',
              centerY: '49%',
              angle: this.mConnectingAngle
            })
            .animation({
              duration: 2000, // 动画时长
              curve: Curve.Linear, // 动画曲线
              delay: 0, // 动画延迟
              iterations: -1, // 播放次数
              playMode: PlayMode.Normal // 动画模式
            })
        }
        Column({ space: 20 }) {
          if (this.mConnectStatus === WifiConnectStatus.SUCCESS) {
            // 连接成功
            Image($r('app.media.icon_connect_wifi_success'))
              .width(80)
              .height(80)
              .objectFit(ImageFit.Contain)
            Text($r('app.string.connect_wifi_success'))
              .fontSize(32)
              .fontColor($r('app.color.connect_wifi_text'))
            Text(this.mConnectSsid)
              .fontSize(22)
              .fontColor($r('app.color.connect_wifi_text'))
          } else if (this.mConnectStatus === WifiConnectStatus.FAIL) {
            // 连接失败
            Image($r('app.media.icon_connect_wifi_fail'))
              .width(80)
              .height(80)
              .objectFit(ImageFit.Contain)
            Text(this.mConnectFailResource)
              .fontSize(32)
              .fontColor($r('app.color.connect_wifi_text'))
            Button($r('app.string.reconnect_wifi'))
              .width(260)
              .height(55)
              .backgroundColor($r('app.color.connect_fail_but_bg'))
              .onClick(() => {
                this.gotoIndex()
              })
          } else {
            // 连接中
            Image($r('app.media.icon_connect_wifi'))
              .width(100)
              .height(100)
              .objectFit(ImageFit.Contain)
            Text($r('app.string.connect_wifi_hint'))
              .fontSize(16)
              .fontColor($r('app.color.connect_wifi_text'))
            Text($r('app.string.connecting_wifi'))
              .fontSize(32)
              .fontColor($r('app.color.connect_wifi_text'))
            Text(this.mConnectSsid)
              .fontSize(22)
              .fontColor($r('app.color.connect_wifi_text'))
          }
        }
        .width('100%')
        .height('100%')
        .justifyContent(FlexAlign.Center)
        .alignItems(HorizontalAlign.Center)
      }
      .width('100%')
      .height('80%')
    }
    .width('100%')
    .height('100%')
    .backgroundColor($r('app.color.connect_bg'))
  }
}

整个界面比较简单，主要显示当前的连接状态：连接中、连接成功、连接超时，特别强调连接超时，计划热点最长连接60s，如果在预定时间未连接成功，则显示超时，超时后可以通过重新配网按钮进行重新扫码连接，根据实际测试，在热点未打开状态下扫码连接耗时平均值12s。

亮点：

界面中最大的亮点，增加了一个发光圆形的属性动画animation，圆形在2s内绕着z轴旋从0度转到360度。

Image($r('app.media.bg_connect_wifi'))
            .width('100%')
            .height('100%')
            .objectFit(ImageFit.Contain)
            .rotate({
              x: 0,
              y: 0,
              z: 1,
              centerX: '50%',
              centerY: '49%',
              angle: this.mConnectingAngle
            })
            .animation({
              duration: 2000, // 动画时长
              curve: Curve.Linear, // 动画曲线
              delay: 0, // 动画延迟
              iterations: -1, // 播放次数
              playMode: PlayMode.Normal // 动画模式
            })

六、网络自动连接

说明：网络自动连接主要是通过@ohos.wifiManager(WLAN)提供的连接接口实现，具体代码如下：

import wifi from '@ohos.wifiManager'
import { Logger } from '@ohos/common'
const TAG: string = '[WiFiModel]'
export type WifiType = {
  ssid: string,
  bssid: string,
  securityType: wifi.WifiSecurityType,
  rssi: number,
  band: number,
  frequency: number,
  timestamp: number
}
export class WifiModel {
  async getScanInfos(): Promise<Array<WifiType>> {
    Logger.info(TAG, 'scanWifi begin')
    let wifiList: Array<WifiType> = []
    let result: Array<wifi.WifiScanInfo> = []
    try {
      result = await wifi.getScanResults()
    } catch (err) {
      Logger.info(TAG, `scan info err: ${JSON.stringify(err)}`)
      return wifiList
    }
    Logger.info(TAG, `scan info call back: ${result.length}`)
    for (var i = 0; i < result.length; ++i) {
      wifiList.push({
        ssid: result[i].ssid,
        bssid: result[i].bssid,
        securityType: result[i].securityType,
        rssi: result[i].rssi,
        band: result[i].band,
        frequency: result[i].frequency,
        timestamp: result[i].timestamp
      })
    }
    return wifiList
  }
  connectNetwork(wifiSsid: string, psw: string, securityType : number): void {
    Logger.debug(TAG, `connectNetwork bssid=${wifiSsid} securityType:${securityType}`)
    // securityType 加密类型默认：Pre-shared key (PSK)加密类型
    let deviceConfig: wifi.WifiDeviceConfig  = {
      ssid: wifiSsid,
      preSharedKey: psw,
      isHiddenSsid: false,
      securityType: securityType
    }
    try {
      wifi.connectToDevice(deviceConfig)
      Logger.info(TAG, `connectToDevice success`)
    } catch (err) {
      Logger.error(TAG, `connectToDevice fail err is ${JSON.stringify(err)}`)
    }
    try {
      wifi.addDeviceConfig(deviceConfig)
    } catch (err) {
      Logger.error(TAG, `addDeviceConfig fail err is ${JSON.stringify(err)}`)
    }
  }
}

网络连接主要是通过wifi.connectToDevice(deviceConfig)实现，其中：deviceConfig: wifi.WifiDeviceConfig为WLAN配置信息，在连接网络时必填三个参数ssid、preSharedKey、securityType。

ssid：热点的SSID。
preSharedKey：热点密钥。
securityType：加密类型。

注意：在调用connectToDevice()函数连接网络时，如果网络已经连接，则需要先调用disconnect()接口断开网络后再执行。

至此，你已经完成了扫码即可连接网络的应用。

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