从 PagingSource 的 LoadResult.Error 中提取 Throwable

idd*_*lip 3 android android-paging-3

我的PagingSource加载一些数据。文档建议捕获这样的异常,以便将来进行某些处理LoadResult.Error 。

 override suspend fun load(params: LoadParams<Int>): LoadResult<Int, Item> {
            return try {
                ...
                throw SomeCatchableException()
                ...
            } catch (e: SomeCatchableException) {
                LoadResult.Error(e)
            } catch (e: AnotherCatchableException) {
                LoadResult.Error(e)
            }
        }
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但是当我尝试这样处理时:

(adapter as PagingDataAdapter).loadStateFlow.collectLatest { loadState ->

                when (loadState.refresh) {
                    is LoadState.Loading -> {
                        // *do something in UI*
                    }
                    is LoadState.Error -> {
                        // *here i wanna do something different actions, whichever exception type*
                    }
                }
            }
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我想知道哪个 Exteption 将被捕获,因为我在参数LoadResult.Error(e)中传递了它(Throwable)

我如何知道loadState处理中的异常类型?

小智 8

在 LoadState.Error 的情况下,您可以从 loadState.refresh 捕获错误,您只是错过了将 loadState.refresh 转换为 LoadState.Error 的操作。或者尝试这样:

when (val currentState = loadState.refresh) {
   is LoadState.Loading -> {
      ...
   }
   is LoadState.Error -> {
       val extractedException = currentState.error // SomeCatchableException
       ...
   }
}
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