为何CoordinatorLayout内collectIsPressedAsState()无法检测短按？

在嵌套于CoordinatorLayout的ComposeView中实现了自定义文本按钮，期望按钮根据按压状态切换文字颜色，但仅长按能触发isPressed变为true，短按时无状态变化，文字颜色也不更新。

复现代码 #

Activity代码

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

        val view = this.layoutInflater.inflate(R.layout.activity_main, null)
        setContentView(view)

        findViewById<ComposeView>(R.id.compose_view).setContent {
            CustomTextButton()
        }
    }
}

@Composable
fun CustomTextButton() {
    val interactionSource = remember { MutableInteractionSource() }
    val isPressed by interactionSource.collectIsPressedAsState()
    val color = when (isPressed) {
        true -> Color.Red
        false -> Color.Black
    }

    LaunchedEffect(key1 = isPressed) {
        println("#### isPressed: $isPressed")
    }

    Box(
        modifier = Modifier
            .clickable(
                indication = null,
                interactionSource = interactionSource,
                onClick = { println("#### Box clicked") }
            )
    ) {
        Text(
            text = "CustomTextButton",
            color = color
        )
    }
}

布局文件

<?xml version="1.0" encoding="utf-8"?>

<androidx.coordinatorlayout.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <androidx.compose.ui.platform.ComposeView
        android:id="@+id/compose_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</androidx.coordinatorlayout.widget.CoordinatorLayout>

日志表现 #

• 长按日志：

2023-02-17 13:31:22.598   ...  #### isPressed: true
2023-02-17 13:31:23.047   ...  #### Box clicked
2023-02-17 13:31:23.106   ...  #### isPressed: false

• 短按日志：

2023-02-17 13:33:12.382   ...  #### Box clicked

问题原因 #

这是因为Compose在CoordinatorLayout这类具备滚动特性的容器内的ComposeView中，对按压状态的触发做了延迟处理，目的是区分点击和滚动操作，但导致短按时无法及时触发isPressed状态变更。

解决方案 #

方案1：修改布局文件属性

给ComposeView添加android:descendantFocusability="blocksDescendants"属性，让Compose优先处理触摸事件：

<androidx.compose.ui.platform.ComposeView
    android:id="@+id/compose_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:descendantFocusability="blocksDescendants" />

方案2：自定义触摸事件处理

通过pointerInput直接处理按压逻辑，绕过默认的滚动延迟：

@Composable
fun CustomTextButton() {
    val interactionSource = remember { MutableInteractionSource() }
    val isPressed by interactionSource.collectIsPressedAsState()
    val color = if (isPressed) Color.Red else Color.Black

    LaunchedEffect(isPressed) {
        println("#### isPressed: $isPressed")
    }

    val pressModifier = Modifier.pointerInput(interactionSource) {
        detectTapGestures(
            onPress = {
                try {
                    interactionSource.emit(PressInteraction.Press(it))
                    awaitRelease()
                } finally {
                    interactionSource.emit(PressInteraction.Release(it))
                }
            },
            onTap = {
                println("#### Box clicked")
            }
        )
    }

    Box(modifier = pressModifier) {
        Text(
            text = "CustomTextButton",
            color = color
        )
    }
}

内容的提问来源于stack exchange，提问作者LukeTheNuke