按钮长按结束怎么监听

在 Jetpack Compose 中，如果你想要监听按钮的长按结束，你需要使用 `Modifier.onLongPressGesture` 结合一个 `LaunchedEffect` 或 `CoroutineScope` 来处理。长按手势通常由 `LongPressGestureDetector` 提供，它有一个 `recognizer` 属性，可以提供 `recognizer.state.isRecognized` 这种状态来判断长按是否结束。

下面是一个简单的示例：

import androidx.compose.foundation.Button
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.lazy.LazyColumn
import androidx.compose.foundation.lazy.items
import androidx.compose.foundation.text.Text
import androidx.compose.material.ButtonStyle
import androidx.compose.material.RippleColor
import androidx.compose.material.Surface
import androidx.compose.material.TextButton
import androidx.compose.material.Theme
import androidx.compose.material.colors.Colors
import androidx.compose.material.shape.Circle
import androidx.compose.material.shape.Shape
import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.geometry.Size
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp
import kotlinx.coroutines.CoroutineScope

@Composable
fun ButtonLongPressExample() {
    val coroutineScope = rememberCoroutineScope()

    Surface(color = Colors.Gray暗色背景) {
        Column(modifier = Modifier.fillMaxSize()) {
            LazyColumn(
                contentPadding = 16.dp,
                spacing = 8.dp
            ) {
                items(5) { index ->
                    Button(
                        onClick = {},
                        modifier = Modifier.onLongPressGesture(
                            recognized = { /* your gesture logic goes here */ },
                            initialVelocityThreshold = 1f,
                            maxDurationMs = 700,
                            minDragDistancePx = 40 // 长按需拖动的距离
                        )
                    ) {
                        Text(text = "Item $index", style = MaterialTheme.typography.body1)
                    }
                }
            }
            Button(onLongPressEnd = { coroutineScope.launch {
                println("长按已结束!")
            }}) {
                Text("长按结束监听")
            }
        }
    }
}

在这个例子中，`onLongPressEnd` 参数会接收一个函数，当长按结束时，这个函数将在协程上下文中运行并打印一条消息。