主要问题是NewsState，MainActivity中的newsItemEvent也有问题。
首先从NewsItem和shouldShowProgress中删除NewState作为布尔值

@Composable
fun NewsItem(
    modifier: Modifier = Modifier,
    articleModel: ArticleModel,
    onNewsLinkClicked: (newsLink: String) -> Unit,
    newsItemEvent: (NewsItemEvent) -> Unit,
    shouldShowProgress:Boolean = false,
//    newsItemState: NewsItemState,
    titleTextLayoutResult: (hasVisualOverflow: Boolean, lineCount: Int) -> Boolean
)

然后在setContent中通过设置

val lambda = remember {
            { newsItemEvent: NewsItemEvent ->
                newsViewModel.onNewsItemEvent(newsItemEvent)
            }
        }
        val themeLambda = remember {
            { appTheme:AppTheme->
                newsApplication.toggleDarkThemeOff(appTheme)
            }
        }

打电话给新闻网

NewsScreen(
    newsPagingData = newsHeadLines,
    modifier = Modifier
        .fillMaxSize()
        .nestedScroll(connection = scrollBehavior.nestedScrollConnection),
    topAppBarScrollBehavior = scrollBehavior,
    onNewsLinkedClicked = { newsLink ->
        newsLinkState = newsLink
    },
    newsItemState = newsItemState,
    newsItemEvent = { newsItemEvent ->
//                                newsViewModel.onNewsItemEvent(newsItemEvent)
        lambda.invoke(newsItemEvent)
    },
    selectedTheme = useDarkColors,
    onSelectedTheme = { appTheme ->
//                                newsApplication.toggleDarkThemeOff(appTheme)
        themeLambda(appTheme)
    }
)

这些将消除NewsItem重组，但LazyColumn将被重组，因为NewsItemItems读取NewsState。我还在NewsItemsItems中创建了一个lambda，但这是可选的，我不认为它在任何情况下都有效。

val textLayoutResultLambda = remember {
    { hasVisualOverflow: Boolean, lineCount: Int ->
        getTextLayoutResult(hasVisualOverflow, lineCount)
    }
}

我还更新了NewState，删除了可变参数，但无论如何它仍然会触发重组。你应该关注为什么NewsState触发了不必要的重组。

@Immutable
data class NewsItemState(
    val shouldShowProgress: Boolean = false,
    val showMoreOrLessTitleText: ShowMoreOrLessTitleText = ShowMoreOrLessTitleText(),
//    val showMoreTitleClicked: Boolean = false,
    val shouldShowMoreTitle: Boolean = true,
    val shouldMoreDescriptionClicked: Boolean = false,
    val shouldShowMoreDescription: Boolean = false,
    val isDarkThemeSelected: Boolean = false
)
/** Work in-progress*/
data class ShowMoreOrLessTitleText(
    val text: String = "Show more",
    val shouldShowMoreTitle: Boolean = false,
    val hasTextOverflow: Boolean = false,
    val lineCount: Int = -1
)
fun ShowMoreOrLessTitleText.textUpdate(): String {
    return if(this.shouldShowMoreTitle)
        "Show more"
    else
        "Show less"
}
fun ShowMoreOrLessTitleText.shouldMoreText(): Boolean {
    return this.hasTextOverflow || lineCount > 1
}

在ViewModel中，您可以将其更新为

is NewsItemEvent.OnShowMoreTitleTextClicked -> {
    _newsItemState.update { newsItemState ->
        val showMoreOrLessTitleText = newsItemState.showMoreOrLessTitleText.copy(
            lineCount = newsItemEvent.showMoreOrLessTitleText.lineCount,
            hasTextOverflow = newsItemEvent.showMoreOrLessTitleText.hasTextOverflow,
            shouldShowMoreTitle =  newsItemState.showMoreOrLessTitleText.shouldMoreText(),
            text =   newsItemState.showMoreOrLessTitleText.textUpdate(),
            )
        newsItemState.copy(
            showMoreOrLessTitleText = showMoreOrLessTitleText
        )
    }
}

这样做一个rememberLazyListState：

val lazyColumnListState = rememberLazyListState()

然后将它传递给LazyColumn，如下所示：

LazyColumn(
    state = lazyColumnListState,
    modifier = Modifier.fillMaxWidth(),
    contentPadding = PaddingValues(start = 8.dp, end = 8.dp, top = 8.dp),
    verticalArrangement = Arrangement.spacedBy(6.dp),
    horizontalAlignment = Alignment.CenterHorizontally
) {
    items(
        key = { articleModel ->
            articleModel.id
        },
        items = newsPagingData.itemSnapshotList.items
    ) { articleModel ->
        NewsItem(
            articleModel = articleModel,
            onNewsLinkClicked = onNewsLinkedClicked,
            newsItemEvent = newsItemEvent,
            newsItemState = newsItemState,
            titleTextLayoutResult = ::getTextLayoutResult
        )
    }
}