HarmonyOS 组件截图然后保存到相册中后无法显示，尺寸为0

async savePhotoFromComponentSnapshot() { 
  let pixmap: image.PixelMap = await componentSnapshot.get('root'); 
  let savePath = await this.getPhotoPicker("test.png") 
  this.savePixmap(pixmap, savePath) 
} 
 
async getPhotoPicker(photoName: string): Promise<string> { 
  // 拉起 photoPicker 获取保存路径 
  let photoSaveOptions = new picker.PhotoSaveOptions(); 
  let photoPicker = new picker.PhotoViewPicker; 
  photoSaveOptions.newFileNames = [photoName]; 
  let photoSaveResult: Array<string> = await photoPicker.save(photoSaveOptions); 
  let savePath = photoSaveResult[0]; 
  return savePath; 
} 
 
async packingPixelMap2Jpg(pixelMap: image.PixelMap): Promise<ArrayBuffer> { 
  // pixel 转 jpg 
  // 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/png", quality: 98 }; 
  let imageBuffer: ArrayBuffer = new ArrayBuffer(10); 
  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; 
} 
 
async savePixmap(pixelMap: image.PixelMap, savePath: string) { 
  // 保存位图 
  const imageBuffer = await this.packingPixelMap2Jpg(pixelMap); 
  try { 
    const file = fs.openSync(savePath, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE); 
    fs.writeSync(file.fd, imageBuffer); 
    fs.closeSync(file); 
  } 
  catch (err) { 
    console.error(`Invoke copyFile failed, err: ${JSON.stringify(err)}`); 
  } 
}