HarmonyOS 有没有类似从View里面获取当前显示的图像，保存成图片文件的方法？

可以用组件截图，文档如下：

https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-arkui-componentsnapshot-V5

import componentSnapshot from '@ohos.arkui.componentSnapshot'
import image from '@ohos.multimedia.image'
@Entry
@Component
struct waterMarkPage {
  @State pixmap: image.PixelMap | undefined = undefined
  build() {
    Column() {
      Stack({ alignContent: Alignment.Center }){
        Image($r('app.media.ic_product02')).autoResize(true).width(300).height(300)
        Row() {
          Text("水印").width(40).height(20).fontSize(16).fontColor(Color.White)
            .border({ color: Color.Red, width: 1 }).borderRadius(4)
            .margin({top:10,right:10})
        }
        .width(300).height(300)
        .alignItems(VerticalAlign.Top)
        .justifyContent(FlexAlign.End)
        Row() {
          Image($r('app.media.startIcon')).autoResize(true).width(40).height(40).margin({bottom:10,right:10})
        }
        .width(300).height(300)
        .alignItems(VerticalAlign.Bottom)
        .justifyContent(FlexAlign.End)
      }
      .id("root")
      Button("生成水印图片")
        .onClick(() => {
          componentSnapshot.get("root")
            .then((pixmap: image.PixelMap) => {
              this.pixmap = pixmap
            }).catch((err:Error) => {
            console.log("error: " + err)
          })
        }).margin(10)
      Image(this.pixmap).width(300).height(300).border({ color: Color.Blue, width: 1 }).margin(5)
    }
    .width('100%')
    .height('100%')
    .alignItems(HorizontalAlign.Center)
  }
}

pixelMap保存到相册：

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);
  try {
      // 方式：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: '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
    });
  }
}