HarmonyOS 提供一个分享（share kit）的demo，且在点击分享弹出半模态窗口时能显示待分享视频的预览图

async () => { 
  // 构造SharedData, 至少有一条数据 
  let shareUtd: string = ''; 
  if (canIUse('SystemCapability.DistributedDataManager.UDMF.Core')) { 
    shareUtd = utd.UniformDataType.HYPERLINK; 
  } 
  const color: ArrayBuffer = new ArrayBuffer(96); // 96为需要创建的像素buffer大小，取值为：height * width *4 
  let opts: image.InitializationOptions = { editable: true, pixelFormat: 3, size: { height: 4, width: 6 } } 
  const pixelMap: image.PixelMap = await image.createPixelMap(color, opts); // 此处生成黑色示例图片，可参考 image.createPixelMap API生成自己的图片 
  const imagePackerApi: image.ImagePacker = image.createImagePacker(); 
  const buffer: ArrayBuffer = await imagePackerApi.packing(pixelMap, { 
    format: 'image/jpeg', 
    quality: 20, 
  }) 
  let shareData: systemShare.SharedData = new systemShare.SharedData({ 
    utd: shareUtd, 
    uri: 'https://xxx.xxx.com/asset/1b74c172df045ca8abe742b6896f944c/75d6057d1831d06f15b862dbe3b9e81c.mp4', 
    title: '这是视频Title', 
    description: '这是视频Description', 
    thumbnail: new Uint8Array(buffer) // 视频缩略图 
  }); 
  // 构建ShareController 
  let controller: systemShare.ShareController = new systemShare.ShareController(shareData); 
  // 获取上下文 
  let context = getContext(this) as common.UIAbilityContext; 
  // 传入UIAbility的上下文对象及分享配置，进行系统分享面板显示 
  controller.show(context, { 
    // 选用一种分享模式, 例如大图预览 
    previewMode: systemShare.SharePreviewMode.DEFAULT, 
    // 选用一种选择模式, 例如单选 
    selectionMode: systemShare.SelectionMode.SINGLE 
  }); 
}