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我正在使用第 3 页，但在可用教程中找不到我的用例。基本上我粘贴的是我在文档和所有在线教程中找到的示例，基本上backend.searchUsers(query, nextPageNumber)不适合我的情况，我只需要打电话backend.fetchAList(userId,startRecord,endRecord)，所以基本上我需要询问后端只给我特定范围的页面，假设我每次想要 16 个项目，我想我应该问startRecord:0 endRecord:15然后我不知道如果用户在列表末尾滚动我应该问startRecord:16 endRecord:31等等，直到列表末尾。如何使用 Paging3 实现这一目标？

编辑：我假设我的方法应该像我上面提到的我的用例是：作为用户，我想用 PaginatedData 检索一个列表来填充我的适配器，逐渐加载列表以便使用滚动一定数量的页面然后从后端检索新的，条件是后端有这些字段： startRecord: Int; endRecord:Int, hasNextItems: Boolean, List, totalItems: Int

class ExamplePagingSource(
    val backend: ExampleBackendService,
    val query: String
) : PagingSource<Int, User>() {
  override suspend fun load(
    params: LoadParams<Int>
  ): LoadResult<Int, User> {
    try {
      // Start refresh at page 1 if undefined.
      val nextPageNumber = params.key ?: 1
      val response = backend.searchUsers(query, nextPageNumber)
      return LoadResult.Page(
        data = response.users,
        prevKey = null, // Only paging forward.
        nextKey = response.nextPageNumber
      )
    } catch (e: Exception) {
      // Handle errors in this block and return LoadResult.Error if it is an
      // expected error (such as a network failure).
    }
  }

  override fun getRefreshKey(state: PagingState<Int, User>): Int? {
    // Try to find the page key of the closest page to anchorPosition, from
    // either the prevKey or the nextKey, but you need to handle nullability
    // here:
    //  * prevKey == null -> anchorPage is the first page.
    //  * nextKey == null -> anchorPage is the last page.
    //  * both prevKey and nextKey null -> anchorPage is the initial page, so
    //    just return null.
    return state.anchorPosition?.let { anchorPosition ->
      val anchorPage = state.closestPageToPosition(anchorPosition)
      anchorPage?.prevKey?.plus(1) ?: anchorPage?.nextKey?.minus(1)
    }
  }
}
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