HarmonyOS鸿蒙Next中如何对拍下照片或相册选中的图片进行压缩并保存的代码示例

相机拍照+图库图片选择保存的Demo：

Index页面：

const TAG = '[CameraDemo]';

@Entry
@Component
struct Index {
  context: Context = getContext(this) as Context;
  @State curFile: string = '';

  build() {
    Column({
      space: 30
    }) {
      Button('拍照')
        .width(200)
        .height(30)
        .onClick(() => {
          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();
          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) {
                return;
              }
            }
            router.pushUrl({
              url: 'pages/CameraDemo'
            })
            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}`);
          })
          margin({ top: 30 })
        })

      Button('图库')
        .width(200)
        .height(30)
        .onClick(() => {
          this.imagePicker();
        })
        .margin({ top: 30 })
    }
    .width('100%')
    .height('100%')
  }

  imagePicker() {
    try {
      let photoSelectOptions = new photoAccessHelper.PhotoSelectOptions();
      photoSelectOptions.MIMEType = photoAccessHelper.PhotoViewMIMETypes.IMAGE_VIDEO_TYPE;
      photoSelectOptions.maxSelectNumber = 1;
      let photoPicker = new photoAccessHelper.PhotoViewPicker();
      photoPicker.select(photoSelectOptions).then((photoSelectResult: photoAccessHelper.PhotoSelectResult) => {
        console.info(TAG, 'PhotoViewPicker.select successfully, PhotoSelectResult uri: ' + JSON.stringify(photoSelectResult));
        this.curFile = photoSelectResult.photoUris[0];
        if (this.curFile) {
          router.pushUrl({
            url: 'pages/FilePickerDemo',
            params: { file: this.curFile, isVideo: this.isVideoType(this.curFile) }
          })
        }
      }).catch((err: BusinessError) => {
        console.error(TAG, 'PhotoViewPicker.select failed with err: ' + JSON.stringify(err));
      });
    } catch (error) {
      let err: BusinessError = error as BusinessError;
      console.error(TAG, 'PhotoViewPicker failed with err: ' + JSON.stringify(err));
    }
  }

  isVideoType(fileUri: string): boolean {
    try {
      let fileExtention = fileUri.substring(fileUri.lastIndexOf('.'));
      let typeId = uniformTypeDescriptor.getUniformDataTypeByFilenameExtension(fileExtention);
      if (typeId == uniformTypeDescriptor.UniformDataType.IMAGE.toString()) {
        return false;
      }

      if (typeId == uniformTypeDescriptor.UniformDataType.VIDEO.toString()) {
        return true;
      }

      let typeObj: uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor(typeId);
      return typeObj.belongingToTypes.some(s => s == uniformTypeDescriptor.UniformDataType.VIDEO.toString())
    } catch (error) {
      let err: BusinessError = error as BusinessError;
      console.error(TAG, 'isVideoType failed with err: ' + JSON.stringify(err));
    }
    return false;
  }
}

CameraDemo页面

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: 1920, height: 1080 };
  @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;

  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();
    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) {
          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}`);
    })
  }

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

    this.cameraManager.on('cameraStatus', (err: BusinessError, cameraStatusInfo: camera.CameraStatusInfo) => {
      console.info(`CameraDemo camera: ${cameraStatusInfo.camera.cameraId}, status: ${cameraStatusInfo.status}`);
    });
  }

  build() {
    Column() {
      Flex({ direction: FlexDirection.Row, justifyContent: FlexAlign.Start }) {
        Image($r('app.media.ic_public_back'))
          .width(30)
          .onClick(() => {
            router.back()
          })
      }

      Column({ space: 20 }) {
        if (this.hasPicture) {
          Image(this.finalPixelMap)
            .objectFit(ImageFit.Fill)
            .width('100%')
            .height(300)

          SaveButton(this.saveButtonOptions)// 创建安全控件按钮
            .onClick(async (event, result: SaveButtonOnClickResult) => {
              if (result == SaveButtonOnClickResult.SUCCESS) {
                if (this.finalPixelMap) {
                  try {
                    let phAccessHelper: photoAccessHelper.PhotoAccessHelper = photoAccessHelper.getPhotoAccessHelper(this.context);
                    let options: photoAccessHelper.CreateOptions = {
                      title: Date.now().toString()
                    };
                    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 {
          XComponent({
            id: '',
            type: 'surface',
            libraryname: '',
            controller: this.mXComponentController
          })
            .onLoad(() => {
              this.mXComponentController.setXComponentSurfaceSize({ surfaceWidth: 1920, surfaceHeight: 1080 });
              this.surfaceId = this.mXComponentController.getXComponentSurfaceId();
              setTimeout(async () => {
                await this.prepareCamera();
              }, 500);
            })
            .width('100%')
            .height(300)
          Image(this.pixelMap)
            .objectFit(ImageFit.Fill)
            .width('100%')
            .height(300)

          Button('拍照')
            .width(200)
            .height(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
              }
              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;
            })
        }
      }
      .width('100%')
      .height('100%')
      .padding(15)
      .borderRadius(8)
    }
    .width('100%')
    .height('100%')
    .backgroundColor('#FFFFFF')
  }

  async prepareCamera() {
    this.createCameraManager();

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

    let cameraDevices: Array<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()}`)
    })

    try {
      this.cameraInput = this.cameraManager.createCameraInput(cameraDevices[0]);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo createCaptureSession error. error: ${JSON.stringify(err)}`);
      return
    }
    this.cameraInput.on('error', cameraDevices[0], (error: BusinessError) => {
      console.error(`CameraDemo Camera input error: ${JSON.stringify(error)}`);
    });

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

    let cameraSceneModes: Array<camera.SceneMode> = [];
    try {
      cameraSceneModes = this.cameraManager.getSupportedSceneModes(cameraDevices[0]);
      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)}`)
    }

    let cameraOutputCapability: camera.CameraOutputCapability = this.cameraManager.getSupportedOutputCapability(cameraDevices[0], 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 && profile.format.valueOf() == 1003) {
        previewProfile = profile;
        return;
      }
    })
    this.imageSize = previewProfile.size;
    console.info(`CameraDemo 选择的预览尺寸: [${previewProfile.size.width},${previewProfile.size.height}], format: ${previewProfile.format.valueOf()}`);

    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
    }
    this.previewOutput.on('error', (error: BusinessError) => {
      console.error(`CameraDemo previewOutput error: ${JSON.stringify(error)}`);
    });

    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
    }
    this.previewOutput2.on('error', (error: BusinessError) => {
      console.error(`CameraDemo previewOutput2 error: ${JSON.stringify(error)}`);
    });

    try {
      let photoProfile = cameraOutputCapability.photoProfiles[0];
      cameraOutputCapability.photoProfiles.forEach(profile => {
        if (profile.size.width == this.imageSize.width && profile.size.height == this.imageSize.height && profile.format.valueOf() == 1003) {
          photoProfile = profile;
          return;
        }
      })
      this.photoOutput = this.cameraManager.createPhotoOutput(photoProfile);
      console.info(`CameraDemo 选择的拍照尺寸: [${previewProfile.size.width},${previewProfile.size.height}], format: ${previewProfile.format.valueOf()}`);
    } 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;
    }

    this.setPhotoOutputCb(this.photoOutput);

    try {
      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
    }
    this.cameraSession.on('error', (error: BusinessError) => {
      console.error(`CameraDemo Capture session error: ${JSON.stringify(error)}`);
    });

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

    try {
      this.cameraSession.addInput(this.cameraInput)
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo addInput error. error: ${JSON.stringify(err)}`);
    }

    try {
      this.cameraSession.addOutput(this.previewOutput)
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo add previewOutput error. error: ${JSON.stringify(err)}`);
    }

    try {
      this.cameraSession.addOutput(this.previewOutput2)
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo add previewOutput2 error. error: ${JSON.stringify(err)}`);
    }

    try {
      this.cameraSession.addOutput(this.photoOutput);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo add photoOutput error. error: ${JSON.stringify(err)}`);
    }

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

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

    this.configuringSession(this.cameraSession)
  }

  configuringSession(photoSession: camera.PhotoSession): void {
    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) {
      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) {
        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)}`);
        }
      }
    }
    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) {
      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)}`);
      }
    }
    let zoomRatioRange: Array<number> = [];
    try {
      zoomRatioRange = photoSession.getZoomRatioRange();
    } 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;
    }
    try {
      photoSession.setZoomRatio(zoomRatioRange[0]);
    } catch (error) {
      let err = error as BusinessError;
      console.error(`CameraDemo Failed to set the zoom ratio value. error: ${JSON.stringify(err)}`);
    }
  }

  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.NV21, // NV21
              sourceSize: this.imageSize
            }
            let imageSource: image.ImageSource = image.createImageSource(imgComponent.byteBuffer, sourceOptions);
            let opts: image.InitializationOptions = {
              editable: true,
              pixelFormat: image.PixelMapFormat.NV21,
              size: this.imageSize
            }
            let pixelMap = await imageSource.createPixelMap(opts);
            await pixelMap.rotate(90.0);
            this.pixelMap = pixelMap;
            await imageSource.release();
          } else {
            return;
          }
          nextImage.release()
        })
      })
    })
  }

  setPhotoOutputCb(photoOutput: camera.PhotoOutput) {
    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}], format: ${value.format.valueOf()}`);
    })
    photoProfileArr.forEach((value: camera.Profile, index: number) => {
      console.info(`CameraDemo 支持的拍照尺寸: [${value.size.width},${value.size.height}], format: ${value.format.valueOf()}`);
    })
    videoProfileArr.forEach((value: camera.VideoProfile, index: number) => {
      console.info(`CameraDemo 支持的录像尺寸: [${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}`);
    })
  }
}

FilePickerDemo 页面

const TAG = '[FilePickerDemo]'

@Entry
@Component
struct FilePickerDemo {
  context: Context = getContext(this) as Context;
  @State curFile: string = '';
  @State uri: string = '';
  @State isVideo: boolean = false;

  aboutToAppear(): void {
    let params = router.getParams() as Record<string, Object>;
    this.curFile = params.file as string;
    this.isVideo = params.isVideo as boolean;
  }

  build() {
    Column({
      space: 10
    }) {
      Flex({
        direction: FlexDirection.Row,
        justifyContent: FlexAlign.Start
      }) {
        Image($r('app.media.ic_public_back'))
          .width(30)
          .onClick(() => {
            router.back()
          })
      }

      if (!this.isVideo) {
        Image(this.curFile)
          .width('100%')
          .height(300)
      } else {
        Video({src: this.curFile})
          .width('100%')
          .height(300)
      }


      Button('图库')
        .onClick(() => {
          this.imagePicker();
        })

      Button('另存到文件管理器')
        .onClick(() => {
          this.saveFile2FileManager();
        })
    }
    .height('100%')
    .width('100%')
  }

  imagePicker() {
    try {
      let photoSelectOptions = new photoAccessHelper.PhotoSelectOptions();
      photoSelectOptions.MIMEType = photoAccessHelper.PhotoViewMIMETypes.IMAGE_VIDEO_TYPE;
      photoSelectOptions.maxSelectNumber = 1;
      let photoPicker = new photoAccessHelper.PhotoViewPicker();
      photoPicker.select(photoSelectOptions).then((photoSelectResult: photoAccessHelper.PhotoSelectResult) => {
        console.info(TAG, 'FilePreviewDemo PhotoViewPicker.select successfully, PhotoSelectResult uri: ' + JSON.stringify(photoSelectResult));
        if (photoSelectResult.photoUris && photoSelectResult.photoUris.length > 0) {
          this.curFile = photoSelectResult.photoUris[0];
          this.isVideo = this.isVideoType(this.curFile);
        }
      }).catch((err: BusinessError) => {
        console.error(TAG, 'FilePreviewDemo PhotoViewPicker.select failed with err: ' + JSON.stringify(err));
      });
    } catch (error) {
      let err: BusinessError = error as BusinessError;
      console.error(TAG, 'FilePreviewDemo PhotoViewPicker failed with err: ' + JSON.stringify(err));
    }
  }

  async saveFile2FileManager() {
    let fileName = new Date().getTime() + this.curFile.substring(this.curFile.lastIndexOf('.'));
    try {
      let photoPicker = new picker.PhotoViewPicker();
      let photoSaveOptions = new picker.PhotoSaveOptions();
      photoSaveOptions.newFileNames = [fileName];
      await photoPicker.save(photoSaveOptions).then(async (photoSaveResult: Array<string>) => {
        console.info(TAG, 'PhotoViewPicker.save successfully, PhotoSaveResult uri: ' + JSON.stringify(photoSaveResult));
        this.uri = photoSaveResult[0];
        await this.writeFile();
      }).catch((err: BusinessError) => {
        console.error(TAG, 'PhotoViewPicker.save failed with err: ' + JSON.stringify(err));
        return;
      });
    } catch (error) {
      let err: BusinessError = error as BusinessError;
      console.error(TAG, 'saveFile failed with err: ' + JSON.stringify(err));
    }
  }

  async writeFile() {
    try {
      let srcFile = fileIo.openSync(this.curFile, fileIo.OpenMode.READ_ONLY)
      let descFile = fileIo.openSync(this.uri, fileIo.OpenMode.WRITE_ONLY);
      fileIo.copyFileSync(srcFile.fd, descFile.fd)
      fileIo.closeSync(srcFile);
      fileIo.closeSync(descFile);
      promptAction.showToast({ message: `保存成功` })
    } catch (error) {
      let err: BusinessError = error as BusinessError;
      console.error(TAG, 'saveFile2 failed with err: ' + JSON.stringify(err));
    }
  }

  isVideoType(fileUri: string): boolean {
    try {
      let fileExtention = fileUri.substring(fileUri.lastIndexOf('.'));
      let typeId = uniformTypeDescriptor.getUniformDataTypeByFilenameExtension(fileExtention);
      if (typeId == uniformTypeDescriptor.UniformDataType.IMAGE.toString()) {
        return false;
      }

      if (typeId == uniformTypeDescriptor.UniformDataType.VIDEO.toString()) {
        return true;
      }

      let typeObj: uniformTypeDescriptor.TypeDescriptor = uniformTypeDescriptor.getTypeDescriptor(typeId);
      return typeObj.belongingToTypes.some(s => s == uniformTypeDescriptor.UniformDataType.VIDEO.toString())
    } catch (error) {
      let err: BusinessError = error as BusinessError;
      console.error(TAG, 'isVideoType failed with err: ' + JSON.stringify(err));
    }
    return false;
  }
}