HarmonyOS 保存到相册报错13900012

为什么我使用以下代码保存图片到相册里会提示权限错误： create asset failed with error: 13900012, without medialibrary permission

我的代码如下，我看官网里写这个是不需要手动获取权限的。

public static async saveToSystemPhoto(uiContext: common.Context, filePath: string, suffix?: string): Promise<void> {
  try {
  let context = uiContext;
  let phAccessHelper = photoAccessHelper.getPhotoAccessHelper(context);
  // 需要确保fileUri对应的资源存在
  let fileUri = filePath
  let assetChangeRequest: photoAccessHelper.MediaAssetChangeRequest = photoAccessHelper.MediaAssetChangeRequest.createImageAssetRequest(context, fileUri);
  let promise = await phAccessHelper.applyChanges(assetChangeRequest);
  console.info('createAsset successfully, uri: ' + assetChangeRequest.getAsset().uri);
  return promise
} catch (err) {
  console.error(`create asset failed with error: ${err.code}, ${err.message}`);
}
}