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Android - 如何从 kotlin 流程中读取值?

我有一个房间数据库中的剧集流。我可以毫无问题地将这个流程作为实时数据进行观察。

但我也想在用户单击按钮时读取此流程中的最后一个值。我尝试使用 first() 终端流运算符,但它无法编译。你能帮忙或提出其他建议吗?

从流中读取的非编译尝试:

bd.buttonNext.setOnClickListener {
    lifecycleScope.launch {
        val episode: Episode? = viewModel.episodeFlow().first()           <=== Compile ERROR
        Snackbar.make(bd.root, "episode ${episode?.name}", Snackbar.LENGTH_SHORT).show()
    }
}
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此流程来自 ROOM :

@Query("SELECT * FROM Episode WHERE id = :id")
fun getEpisode(id: Long): Flow<Episode?>
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存储库:

fun getEpisode(episodeId: Long): Flow<Episode?> = dao.getEpisode(episodeId)
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视图模型 - Id 来自 StateFlow :

fun episodeFlow(): Flow<Episode?> 
  = episodeIdStateFlow.flatMapLatest { episodeId ->
    repository.getEpisode(episodeId)
  }
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编译错误:

Unresolved reference. None of the following candidates is applicable because of receiver type mismatch: 
public fun <T> Array<out …
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android kotlin-flow kotlin-coroutines-flow kotlin-stateflow

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