HarmonyOS 自定义相机怎么实现全屏预览和产出的视频、图片的边界一致？

Question

根据文档的描述，预览setXComponentSurfaceRect(rect: SurfaceRect)设置的宽高和后续设置的预览流、输出流的宽高比例一致。然而XComponent的宽高在全屏下和这个比例并不一致。所以最后产出的视频和图片的边界超出了XComponent预览的界面。我知道XComponent比例只要和setXComponentSurfaceRect设置的一致就能实现。我在使用系统相机的时候我看到录像有个全屏模式产物和预览边界一致。怎么实现和XComponent预览边界一致的产物？

Answer 1

试一下如下demo

import { camera } from '@kit.CameraKit';
import { BusinessError } from '@kit.BasicServicesKit';
import { image } from '@kit.ImageKit';
import { photoAccessHelper } from '@kit.MediaLibraryKit';
import { abilityAccessCtrl, PermissionRequestResult, Permissions } from '@kit.AbilityKit';
import { display, promptAction } from '@kit.ArkUI';
import { fileIo } from '@kit.CoreFileKit';
import fs from '@ohos.file.fs';
const TAG = '[CameraDemo]';
@Entry
@Component
struct CameraDemo {
  context: Context = getContext(this) as Context;
  @State pixelMap: image.PixelMap | undefined = undefined;
  @State finalPixelMap: image.PixelMap | undefined = undefined;
  @State buffer: ArrayBuffer | undefined = undefined;
  @State surfaceId: string = '';
  @State hasPicture: boolean = false;
  @State fileNames: string[] = [];
  @State imageSize: image.Size = { width: 4160, height: 1920 };
  @State saveButtonOptions: SaveButtonOptions = {
    icon: SaveIconStyle.FULL_FILLED,
    text: SaveDescription.SAVE_IMAGE,
    buttonType: ButtonType.Capsule
  } // 设置安全控件按钮属性
  private mXComponentController: XComponentController = new XComponentController;
  private cameraManager: camera.CameraManager | undefined = undefined;
  private cameraSession: camera.PhotoSession | undefined = undefined;
  private photoOutput: camera.PhotoOutput | undefined = undefined;
  private cameraInput: camera.CameraInput | undefined = undefined;
  private previewOutput: camera.PreviewOutput | undefined = undefined;
  private previewOutput2: camera.PreviewOutput | undefined = undefined;
  private imageReceiver: image.ImageReceiver | undefined = undefined;
  @State ca :Number  = 1
  @State screenWidth :number  = 0
  @State screenHeight :number  = 0

  aboutToAppear(): void {
    let permissions: Array<Permissions> = [
      'ohos.permission.CAMERA',
      'ohos.permission.WRITE_MEDIA',
      'ohos.permission.READ_MEDIA',
      'ohos.permission.MEDIA_LOCATION',
    ];
    let atManager: abilityAccessCtrl.AtManager = abilityAccessCtrl.createAtManager();
    // requestPermissionsFromUser会判断权限的授权状态来决定是否唤起弹窗
    atManager.requestPermissionsFromUser(this.context, permissions).then((data: PermissionRequestResult) => {
      let grantStatus: Array<number> = data.authResults;
      let length: number = grantStatus.length;
      for (let i = 0; i < length; i++) {
        if (grantStatus[i] != 0) {
          // 用户拒绝授权，提示用户必须授权才能访问当前页面的功能，并引导用户到系统设置中打开相应的权限
          return;
        }
      }
      console.info(`${TAG} Success to request permissions from user. authResults is ${grantStatus}.`);
    }).catch((err: BusinessError) => {
      console.error(`${TAG} Failed to request permissions from user. Code is ${err.code}, message is ${err.message}`);
    })
    let displaydef = display.getDefaultDisplaySync()
    this.screenWidth = displaydef.width
    this.screenHeight = displaydef.height
  }

  createCameraManager() {
    // 创建CameraManager对象
    let cameraManager: camera.CameraManager = camera.getCameraManager(this.context);
    if (!cameraManager) {
      console.error('CameraDemo camera.getCameraManager error');
      return;
    }
    this.cameraManager = cameraManager;

    // 监听相机状态变化
    this.cameraManager.on('cameraStatus', (err: BusinessError, cameraStatusInfo: camera.CameraStatusInfo) => {
      console.info(`CameraDemo camera: ${cameraStatusInfo.camera.cameraId}, status: ${cameraStatusInfo.status}`);
    });
  }

  async onPageShow(){
    await this.prepareCamera(this.ca);
  }

  build() {
    Stack({alignContent: Alignment.BottomStart}) {
      XComponent({
        id: '',
        type: 'surface',
        libraryname: '',
        controller: this.mXComponentController
      })
        .expandSafeArea([SafeAreaType.SYSTEM], [SafeAreaEdge.TOP, SafeAreaEdge.BOTTOM])
        .onLoad(() => {
          let displaydef = display.getDefaultDisplaySync()
          this.mXComponentController.setXComponentSurfaceRect({offsetX:0,offsetY:0, surfaceWidth: displaydef.height * 1920.0/4160.0, surfaceHeight: displaydef.height});
          //this.mXComponentController.setXComponentSurfaceRect({offsetX:0,offsetY:0, surfaceWidth: this.screenHeight*1080.0/1920.0, surfaceHeight: this.screenHeight });
          this.surfaceId = this.mXComponentController.getXComponentSurfaceId();
          setTimeout(async () => {
            await this.prepareCamera(this.ca);
          }, 500);
        })
        .width('100%')
        .height('100%')

      Row(){
        Button('前置摄像头')
          .size({ width: 100, height: 30 }).margin({ right: 10 })
          .onClick(async () => {
            this.ca=1
            console.debug('打开前置摄像头')
            await this.prepareCamera(this.ca);
          })
        Button('拍照').width(60).height(60).margin({ right: 10 }).borderRadius(30)
          .onClick(async () => {
            let photoCaptureSetting: camera.PhotoCaptureSetting = {
              quality: camera.QualityLevel.QUALITY_LEVEL_HIGH, // 设置图片质量高
              rotation: camera.ImageRotation.ROTATION_0, // 设置图片旋转角度0
              mirror: true // 开启镜像
            }
            // 1、通过拍照流实现：点击拍照
            await this.photoOutput?.capture(photoCaptureSetting).catch((error: BusinessError) => {
              console.error(`CameraDemo Failed to capture the photo ${error.message}`); //不符合条件则进入
            })
            this.hasPicture = true;
          })
        Button('后置摄像头')
          .size({ width: 100, height: 30 }).margin({ left: 10 })
          .onClick(async () => {
            this.ca=0
            console.debug('打开后置摄像头')
            await this.prepareCamera(this.ca);
          })
      }
      .width('100%')
      .justifyContent(FlexAlign.SpaceAround)

      if (this.hasPicture) {
        Image(this.finalPixelMap)
          //.objectFit(ImageFit.Fill)
          .width('100%')
          .height('100%')
          .expandSafeArea([SafeAreaType.SYSTEM], [SafeAreaEdge.TOP, SafeAreaEdge.BOTTOM])

        Row() {
          Button('取消')
            .onClick(() => {
              this.hasPicture = false;
              this.finalPixelMap = undefined;
            })
          SaveButton(this.saveButtonOptions)// 创建安全控件按钮
            .onClick(async (event, result: SaveButtonOnClickResult) => {
              if (result == SaveButtonOnClickResult.SUCCESS) {
                if (this.finalPixelMap) {
                  try {
                    // 1、使用安全控件创建文件
                    let phAccessHelper: photoAccessHelper.PhotoAccessHelper = photoAccessHelper.getPhotoAccessHelper(this.context);
                    let filename = Date.now().toString();
                    let options: photoAccessHelper.CreateOptions = {
                      title: filename
                    };
                    // createAsset的调用需要ohos.permission.READ_IMAGEVIDEO和ohos.permission.WRITE_IMAGEVIDEO的权限
                    let photoUri: string = await phAccessHelper.createAsset(photoAccessHelper.PhotoType.IMAGE, 'png', options);
                    console.info('CameraDemo createAsset successfully, photoUri: ' + photoUri);
                    let file: fileIo.File = fileIo.openSync(photoUri, fileIo.OpenMode.WRITE_ONLY);
                    fileIo.writeSync(file.fd, this.buffer);
                    fileIo.closeSync(file);
                    promptAction.showToast({message: `保存成功`})
                  } catch (error) {
                    let err = error as BusinessError;
                    console.error(`CameraDemo savePicture error: ${JSON.stringify(err)}`);
                    promptAction.showToast({ message: `保存失败` })
                  }
                }
              } else {
                console.error('CameraDemo SaveButtonOnClickResult createAsset failed.');
                promptAction.showToast({ message: `保存失败` })
              }
              setTimeout(() => {
                this.hasPicture = false;
                this.finalPixelMap = undefined;
              }, 1000)
            })
        }

      } else {



      }
    }
    .width('100%')
    .height('100%')
  }

  async prepareCamera(ca:Number) {
    this.releaseCamera()
    this.createCameraManager();

    if (!this.cameraManager) {
      console.error('CameraDemo cameraManager is undefined.')
      return;
    }

    // 获取支持指定的相机设备对象
    let cameraDevices: Array<camera.CameraDevice> = [];
    let CameraDevice:camera.CameraDevice
    try {
      cameraDevices = this.cameraManager.getSupportedCameras();
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo The getSupportedCameras call failed. error: ${JSON.stringify(err)}`)
    }

    cameraDevices.forEach((cameraDevice: camera.CameraDevice) => {
      console.info(`CameraDemo cameraId: ${cameraDevice.cameraId}, cameraPosition: ${cameraDevice.cameraPosition.toString()}, cameraType: ${cameraDevice.cameraType.toString()}, connectionType: ${cameraDevice.connectionType.toString()}`)
    })

    // 创建相机输入流

    try {
      if (ca==0) {
        CameraDevice = cameraDevices[0]
      }else {
        CameraDevice = cameraDevices[1]
      }
      this.cameraInput = this.cameraManager.createCameraInput(CameraDevice);

    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo createCaptureSession error. error: ${JSON.stringify(err)}`);
      return
    }
    // 监听cameraInput错误信息
    this.cameraInput.on('error', CameraDevice, (error: BusinessError) => {
      console.error(`CameraDemo Camera input error: ${JSON.stringify(error)}`);
    });

    // 打开相机
    try {
      await this.cameraInput.open();
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo cameraInput open error. error: ${JSON.stringify(err)}`);
    }

    // 获取指定的相机设备对象支持的模式
    let cameraSceneModes: Array<camera.SceneMode> = [];
    try {
      cameraSceneModes = this.cameraManager.getSupportedSceneModes(CameraDevice);
      cameraSceneModes.forEach((cameraSceneMode: camera.SceneMode) => {
        console.info(`CameraDemo cameraSceneMode: ${cameraSceneMode.toString()}`)
      })
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo The getSupportedSceneModes call failed. error: ${JSON.stringify(err)}`)
    }

    // 获取相机设备支持的输出流能力
    let cameraOutputCapability: camera.CameraOutputCapability = this.cameraManager.getSupportedOutputCapability(CameraDevice, camera.SceneMode.NORMAL_PHOTO)
    if (!cameraOutputCapability) {
      console.error('CameraDemo cameraManager.getSupportedOutputCapability error');
      return;
    }
    this.printCameraOutputCapability(cameraOutputCapability);
    let previewProfile = cameraOutputCapability.previewProfiles[0];
    cameraOutputCapability.previewProfiles.forEach((profile) => {
      if (profile.size.width == this.imageSize.width && profile.size.height == this.imageSize.height) {
        previewProfile = profile;
        return;
      }
    })
    this.imageSize = previewProfile.size;

    // 创建相机预览输出流
    try {
      this.previewOutput = this.cameraManager.createPreviewOutput(previewProfile, this.surfaceId);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo createCaptureSession error. error: ${JSON.stringify(err)}`);
      return
    }
    // 监听previewOutput错误信息
    this.previewOutput.on('error', (error: BusinessError) => {
      console.error(`CameraDemo previewOutput error: ${JSON.stringify(error)}`);
    });

    //双路预览: 创建 预览流2 输出对象
    try {
      this.imageReceiver = image.createImageReceiver(this.imageSize, image.ImageFormat.JPEG, 8);
      let imageReceiverSurfaceId: string = await this.imageReceiver.getReceivingSurfaceId()
      this.previewOutput2 = this.cameraManager.createPreviewOutput(previewProfile, imageReceiverSurfaceId);
      this.onImageArrival(this.imageReceiver);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo createImageReceiver error ${JSON.stringify(err)}`);
      return
    }

    // 创建拍照输出流
    try {
      let photoProfile = cameraOutputCapability.photoProfiles[0];
      cameraOutputCapability.photoProfiles.forEach((profile) => {
        if (profile.size.width == this.imageSize.width && profile.size.height == this.imageSize.height) {
          photoProfile = profile;
          return;
        }
      })
      this.photoOutput = this.cameraManager.createPhotoOutput(photoProfile);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo createPhotoOutput error ${JSON.stringify(err)}`);
    }
    if (this.photoOutput === undefined) {
      console.error('CameraDemo photoOutput is undefined.');
      return;
    }

    //调用上面的回调函数来保存图片
    this.setPhotoOutputCb(this.photoOutput);

    // 创建相机会话
    try {
      // this.cameraSession = this.cameraManager.createCaptureSession();
      this.cameraSession = this.cameraManager.createSession<camera.PhotoSession>(camera.SceneMode.NORMAL_PHOTO);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo createCaptureSession error. error: ${JSON.stringify(err)}`);
      return
    }
    // 监听session错误信息
    this.cameraSession.on('error', (error: BusinessError) => {
      console.error(`CameraDemo Capture session error: ${JSON.stringify(error)}`);
    });

    // 开始会话配置
    try {
      this.cameraSession.beginConfig()
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo beginConfig error. error: ${JSON.stringify(err)}`);
    }

    // 向会话中添加相机输入流
    try {
      this.cameraSession.addInput(this.cameraInput)
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo addInput error. error: ${JSON.stringify(err)}`);
    }

    // 向会话中添加预览输出流
    try {
      this.cameraSession.addOutput(this.previewOutput)
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo add previewOutput error. error: ${JSON.stringify(err)}`);
    }

    // 向会话中添加预览输出流2
    try {
      this.cameraSession.addOutput(this.previewOutput2)
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo add previewOutput2 error. error: ${JSON.stringify(err)}`);
    }

    // 向会话中添加拍照输出流
    try {
      this.cameraSession.addOutput(this.photoOutput);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo add photoOutput error. error: ${JSON.stringify(err)}`);
    }

    // 提交会话配置
    try {
      await this.cameraSession.commitConfig();
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo captureSession commitConfig error: ${JSON.stringify(err)}`);
    }

    // 启动会话
    try {
      await this.cameraSession.start();
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo captureSession start error: ${JSON.stringify(err)}`);
    }

    // 配置相机的参数可以调整拍照的一些功能，包括闪光灯、变焦、焦距等。
    this.configuringSession(this.cameraSession)
  }

  configuringSession(photoSession: camera.PhotoSession): void {
    // 判断设备是否支持闪光灯
    let flashStatus: boolean = false;
    try {
      flashStatus = photoSession.hasFlash();
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo Failed to hasFlash. error: ${JSON.stringify(err)}`);
    }
    console.info(`CameraDemo Returned with the flash light support status: ${flashStatus}`);
    if (flashStatus) {
      // 判断是否支持自动闪光灯模式
      let flashModeStatus: boolean = false;
      try {
        let status: boolean = photoSession.isFlashModeSupported(camera.FlashMode.FLASH_MODE_AUTO);
        flashModeStatus = status;
      } catch (error) {
        let err = error as BusinessError;
        console.error(`CameraDemo Failed to check whether the flash mode is supported. error: ${JSON.stringify(err)}`);
      }
      if (flashModeStatus) {
        // 设置自动闪光灯模式
        try {
          photoSession.setFlashMode(camera.FlashMode.FLASH_MODE_AUTO);
        } catch (error) {
          let err = error as BusinessError;
          console.error(`CameraDemo Failed to set the flash mode. error: ${JSON.stringify(err)}`);
        }
      }
    }
    // 判断是否支持连续自动变焦模式
    let focusModeStatus: boolean = false;
    try {
      let status: boolean = photoSession.isFocusModeSupported(camera.FocusMode.FOCUS_MODE_CONTINUOUS_AUTO);
      focusModeStatus = status;
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo Failed to check whether the focus mode is supported. error: ${JSON.stringify(err)}`);
    }
    if (focusModeStatus) {
      // 设置连续自动变焦模式
      try {
        photoSession.setFocusMode(camera.FocusMode.FOCUS_MODE_CONTINUOUS_AUTO);
      } catch (error) {
        let err = error as BusinessError;
        console.error(`CameraDemo Failed to set the focus mode. error: ${JSON.stringify(err)}`);
      }
    }
    // 获取相机支持的可变焦距比范围
    let zoomRatioRange: Array<number> = [];
    try {
      zoomRatioRange = photoSession.getZoomRatioRange();
      zoomRatioRange.forEach(( index: number) => {
        console.info(`zoomRatioRange 支持的焦距: [${index}]`);
      })
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo Failed to get the zoom ratio range. error: ${JSON.stringify(err)}`);
    }
    if (zoomRatioRange.length <= 0) {
      return;
    }
    // 设置可变焦距比
    try {
      photoSession.setZoomRatio(1);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo Failed to set the zoom ratio value. error: ${JSON.stringify(err)}`);
    }
  }

  // 通过Surface进行数据传递，通过ImageReceiver的surface获取预览图像。
  async onImageArrival(receiver: image.ImageReceiver): Promise<void> {
    receiver.on('imageArrival', () => {
      receiver.readNextImage(async (err, nextImage: image.Image) => {
        //console.info(`enter CameraDemo imageArrival, nextImage: ${JSON.stringify(nextImage)}`)
        if (err || nextImage === undefined) {
          console.error(`CameraDemo imageArrival error, error is ${JSON.stringify(err)} or nextImage is undefined`)
          return;
        }
        nextImage.getComponent(image.ComponentType.JPEG, async (err, imgComponent: image.Component) => {
          if (err || imgComponent === undefined) {
            console.error(`CameraDemo getComponent error, error is ${JSON.stringify(err)} or imgComponent is undefined`)
            return;
          }
          if (imgComponent.byteBuffer as ArrayBuffer) {
            let sourceOptions: image.SourceOptions = {
              sourceDensity: 0,
              sourcePixelFormat: image.PixelMapFormat.NV12, // NV21
              sourceSize: this.imageSize
            }
            let imageSource: image.ImageSource = image.createImageSource(imgComponent.byteBuffer, sourceOptions);
            let opts: image.InitializationOptions = {
              editable: false,
              pixelFormat: image.PixelMapFormat.NV21,
              size: this.imageSize
            }
            let pixelMap = await imageSource.createPixelMap(opts);
            await pixelMap.rotate(270.0);
            this.pixelMap = pixelMap;
            await imageSource.release();
          } else {
            return;
          }
          nextImage.release()
        })
      })
    })
  }


  setPhotoOutputCb(photoOutput: camera.PhotoOutput) {
    //设置回调之后，调用photoOutput的capture方法，就会将拍照的buffer回传到回调中
    photoOutput.on('photoAvailable', (errCode: BusinessError, photo: camera.Photo): void => {
      console.info(`CameraDemo getPhoto start. err: ${JSON.stringify(errCode)}`);
      if (errCode || photo === undefined || photo.main === undefined) {
        console.error('CameraDemo getPhoto failed');
        return;
      }
      let imageObj = photo.main;
      imageObj.getComponent(image.ComponentType.JPEG, async (errCode: BusinessError, component: image.Component): Promise<void> => {
        console.info('CameraDemo getComponent start');
        if (errCode || component === undefined) {
          console.error('CameraDemo getComponent failed');
          return;
        }
        let buffer: ArrayBuffer;
        if (component.byteBuffer) {
          buffer = component.byteBuffer;
          this.buffer = buffer;
          let sourceOptions: image.SourceOptions = {
            sourceDensity: 0, // 在不确定当前密度时传0
            sourcePixelFormat: image.PixelMapFormat.RGBA_8888,
            sourceSize: this.imageSize
          }
          let imageSource: image.ImageSource = image.createImageSource(buffer, sourceOptions);
          let opts: image.InitializationOptions = {
            editable: false,
            pixelFormat: image.PixelMapFormat.RGBA_8888,
            size: this.imageSize
          }
          let pixelMap = await imageSource.createPixelMap(opts);
          this.finalPixelMap = pixelMap;
        } else {
          console.error('CameraDemo byteBuffer is null');
          return;
        }
      });
    });
  }

  printCameraOutputCapability(cameraOutputCapability: camera.CameraOutputCapability) {
    // let previewProfileArr: Array<camera.Profile> = cameraOutputCapability.previewProfiles;
    // let photoProfileArr: Array<camera.Profile> = cameraOutputCapability.photoProfiles;
    // let videoProfileArr: Array<camera.VideoProfile> = cameraOutputCapability.videoProfiles;
    // let supportedMetadataObjectTypeArr: Array<camera.MetadataObjectType> = cameraOutputCapability.supportedMetadataObjectTypes;
    // previewProfileArr.forEach((value: camera.Profile, index: number) => {
    //   console.info(`CameraDemo 支持的预览尺寸: [${value.size.width},${value.size.height}]`);
    // })
    // photoProfileArr.forEach((value: camera.Profile, index: number) => {
    //   console.info(`CameraDemo 支持的拍照尺寸: [${value.size.width},${value.size.height}]`);
    // })
    // videoProfileArr.forEach((value: camera.VideoProfile, index: number) => {
    //   console.info(`CameraDemo 支持的录像尺寸: [${value.size.width},${value.size.height}], 支持的帧率范围: [${value.frameRateRange.min},${value.frameRateRange.max}]`);
    // })
    // supportedMetadataObjectTypeArr.forEach((value: camera.MetadataObjectType, index: number) => {
    //   console.info(`CameraDemo 支持的metadata流类型: ${value}`);
    // })
  }

  releaseCamera() {
    if (this.cameraInput) {
      this.cameraInput.close()
    }
    if (this.previewOutput) {
      this.previewOutput.release()
    }
    if (this.photoOutput) {
      this.photoOutput.release()
    }
    if (this.cameraSession) {
      this.cameraSession.release()
    }
  }

  async imageWriteAlbumExample(pixelMap?:image.PixelMap) {
    console.info('createAssetDemo');
    let context = getContext(this);
    let phAccessHelper = photoAccessHelper.getPhotoAccessHelper(context);
    let photoType: photoAccessHelper.PhotoType = photoAccessHelper.PhotoType.IMAGE;
    let extension:string = 'jpg';
    let options: photoAccessHelper.CreateOptions = {
      title: 'testPhoto'
    }
    let uri = await phAccessHelper.createAsset(photoType, extension, options);
    // 使用uri打开文件，可以持续写入内容，写入过程不受时间限制
    try {
      if(pixelMap){
        // 方式一：通过文件管理写入文件
        let file =  fs.openSync(uri, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);
        const imageBuffer = await this.packingPixelMap2Jpg(pixelMap as image.PixelMap)
        // 写到媒体库文件中
        fs.writeSync(file.fd, imageBuffer);
        fs.closeSync(file.fd);
        // 方式二：通过imagePacker写入文件
        // let file: fs.File = fs.openSync(uri, fs .OpenMode.WRITE_ONLY);
        // let imagePacker: image.ImagePacker = image.createImagePacker();
        // let packOpts: image.PackingOption = { format: 'image/jpeg', quality: 100 };
        // await imagePacker.packToFile(pixelMap , file.fd, packOpts);
        // fs.closeSync(file);
      }
      promptAction.showToast({message: `保存成功`})
      promptAction.showToast({
        message: '已保存至相册',
        duration: 2500
      });

    }
    catch (err) {
      console.error("error is "+ JSON.stringify(err))
      promptAction.showToast({
        message: '保存失败',
        duration: 2000
      });
    }
  }

  async  packingPixelMap2Jpg(pixelMap: PixelMap): Promise<ArrayBuffer> {
    // 创建ImagePacker实例
    const imagePackerApi = image.createImagePacker();
    // 设置打包参数
    // format：图片打包格式，只支持 jpg 和 webp
    // quality：JPEG 编码输出图片质量
    // bufferSize：图片大小，默认 10M
    const packOpts: image.PackingOption = { format: "image/jpeg", quality: 100 };
    let imageBuffer: ArrayBuffer = new ArrayBuffer(1);
    try {
      // 图片压缩或重新打包
      imageBuffer = await imagePackerApi.packing(pixelMap, packOpts);
    } catch (err) {
      console.error(`Invoke packingPixelMap2Jpg failed, err: ${JSON.stringify(err)}`);
    }
    return imageBuffer;
  }

}