【发布时间】:2022-01-02 08:09:52
【问题描述】:
我正在使用下面的分页源实现从网络获取数据并通过collectAsLazyPagingItems() 以可组合方式观察它。但是,在此LazyPagingItems 上调用refresh() 方法时,它不是从page 0 获取数据,而是从最后获取的页码获取数据,这导致没有数据可显示。这里有什么问题?难道是因为val page = params.key ?: 0?
class CommentDataSource(
private val postId: Long,
private val commentApi: CommentApi
) : PagingSource<Int, Comment>() {
override fun getRefreshKey(state: PagingState<Int, Comment>): Int? {
return state.anchorPosition
}
override suspend fun load(params: LoadParams<Int>): LoadResult<Int, Comment> {
return try {
val page = params.key ?: 0
val responseData = commentApi.getPostComments(
postId = postId,
page = page
).data
LoadResult.Page(
data = responseData.comments,
prevKey = if (page == 0) null else page - 1,
nextKey = if (!responseData.hasNextPage) null else responseData.currentPage + 1
)
} catch (e: IOException) {
LoadResult.Error(e)
} catch (e: HttpException) {
LoadResult.Error(e)
}
}
}
【问题讨论】:
标签: android kotlin android-jetpack-compose android-paging