PhotoPickerComponent 在当前 API 下不暴露任何滚动控制能力（无 Scroller、无 onScroll、无nestedScroll），无法与父组件做真正的 nestedScroll 联动。可以下面2种方式实现相册列表的滚动联动：

1.自绘相册+Grid.nestedScroll(推荐)用 photoAccessHelper 读取媒体库，用Grid/WaterFlow 自绘相册列表。Grid支持.nestedScroll0属性，可与父Scroll实现完美的PARENT_FIRST/SELF_FIRST 联动，能完整复刻小红书/抖音个人页的吸顶效果。需自实现大图预览、勾选、相机入口等UI(PhotoPickerComponent提供的能力)

2.外层Scroll+高度动态切换把Header/Tabs/PhotoPickerComponent-起放到卜层Scroll，PhotoPickerComponent高度固定1屏，让用户先滚Header，收起后 PhotoPickerComponent独立滚。视觉上接近吸顶但效果割裂。

我用的是第2种办法：

import {
  PhotoPickerComponent,
  PickerController,
  PickerOptions,
  ItemInfo,
  ItemType,
  ClickType,
  ReminderMode
} from '@kit.MediaLibraryKit';
import { photoAccessHelper } from '@kit.MediaLibraryKit';

const DEFAULT_PICKER_HEIGHT: number = 480;

@Component
export struct EmbeddedPhotoPicker {
  @Prop isVisible: boolean = true;
  @State pickerOptions: PickerOptions = new PickerOptions();
  @ObjectLink pickerController: PickerController;
  @Prop maxCount: number = 1;
  @Prop pickerHeight: number = DEFAULT_PICKER_HEIGHT;
  onPhotoPicked: (uri: string) => void = (uri: string): void => {};

  aboutToAppear(): void {
    this.pickerOptions.MIMEType = photoAccessHelper.PhotoViewMIMETypes.IMAGE_TYPE;
    this.pickerOptions.maxSelectNumber = this.maxCount;
    this.pickerOptions.maxSelectedReminderMode = ReminderMode.TOAST;
    this.pickerOptions.isSearchSupported = true;
    this.pickerOptions.isPhotoTakingSupported = true;
  }

  private onItemClicked(itemInfo: ItemInfo, clickType: ClickType): boolean {
    if (!itemInfo) {
      return false;
    }
    if (itemInfo.itemType === ItemType.CAMERA) {
      return true;
    }
    if (clickType === ClickType.SELECTED && itemInfo.uri) {
      this.onPhotoPicked(itemInfo.uri);
    }
    return true;
  }

  build() {
    Column() {
      Row() {
        Text('从相册选择')
          .fontSize($r('app.integer.subtitle_text_M'))
          .fontWeight(FontWeight.Medium)
          .fontColor($r('app.color.font_primary'))
          .layoutWeight(1)
        Text('✕')
          .fontSize(20)
          .fontColor($r('app.color.font_tertiary'))
          .padding(8)
          .onClick(() => {
            this.isVisible = false;
          })
      }
      .width('100%')
      .height(48)
      .padding({ left: 16, right: 8 })
      .alignItems(VerticalAlign.Center)
      .backgroundColor($r('app.color.background_primary'))

      PhotoPickerComponent({
        pickerOptions: this.pickerOptions,
        pickerController: this.pickerController,
        onItemClicked: (itemInfo: ItemInfo, clickType: ClickType): boolean => this.onItemClicked(itemInfo, clickType)
      })
        .width('100%')
        .layoutWeight(1)
        .backgroundColor($r('app.color.background_secondary'))
    }
    .width('100%')
    .height(this.pickerHeight)
    .borderRadius(16)
    .backgroundColor($r('app.color.background_primary'))
    .clip(true)
  }
}

把最小demo发出来我研究下