android compose PullToRefreshAndLoadMore 下拉刷新 + 上拉加载更多 使用

android compose PullToRefreshAndLoadMore 下拉刷新 + 上拉加载更多 使用

/**
 * Author : wn
 * Email : maoning20080809@163.com
 * Date : 2026/1/6 20:23
 * Description : 下拉刷新 + 上拉加载更多
 */
class PullToRefreshActivity : ComponentActivity(){

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        setContent {
            testPullToRefreshAndLoadMoreDemo()
        }
    }

    @Preview
    @Composable
    private fun testPullToRefreshAndLoadMoreDemo(){
        var refreshing by remember { mutableStateOf(false) }
        var loadingMore by remember { mutableStateOf(false) }

        var items by remember { mutableStateOf<ArrayList<String>>(arrayListOf()) }
        var page by remember { mutableStateOf(1) }

        //初始化加载数据
        LaunchedEffect(Unit) {
            items = loadData(page)
        }

        //下拉刷新
        LaunchedEffect(refreshing) {
            if(refreshing){
                delay(1500)
                page = 1
                items = loadData(page)
                refreshing = false
            }
        }

        //上拉加载更多
        LaunchedEffect(loadingMore) {
            if(loadingMore){
                delay(1500)
                page++
                val newItemList = loadData(page)
                items.addAll(newItemList)
                loadingMore = false
            }
        }

        Text(text = "PullToRefreshAndLoadMore 下拉刷新 下拉加载更多", color = Color.Red)
        SwipeRefresh(state = rememberSwipeRefreshState(refreshing),
            onRefresh = {
                refreshing = true
            }) {
            LazyColumn() {
                items(items.size){index ->
                    Text(text = items[index], modifier = Modifier.fillMaxWidth().padding(16.dp))
                    //检测是否滚动到底部
                    if(index == items.size -1 && !loadingMore && !refreshing){
                        loadingMore = true
                    }
                }

                //显示加载更多指示器
                if(loadingMore){
                    item{
                        Box(modifier = Modifier.fillMaxWidth().padding(16.dp),
                            contentAlignment = Alignment.Center){
                            CircularProgressIndicator()
                        }
                    }
                }
            }
        }
    }

    private suspend fun loadData(page : Int) : ArrayList<String>{
        //模拟网络请求
        //delay(500)
        return List(20){"Item ${(page - 1) * 20 + it + 1}"}.toCollection(ArrayList())
    }
}