Android 根据 Jetpack Compose 中的生命周期正确处理变量函数

我想在Jetpack编写中根据生命周期更改变量值或调用函数.我试着按这answer来算.也是从doc开始读的.我做了这件事，没有任何问题.

我有@Composable个功能

@Composable
fun BluetoothConnectionContentStateful(
    context: Context = LocalContext.current,
    viewModel: PairViewModel = getViewModel()
) {
    var selectedIndexOfAvailableItem by remember { mutableStateOf(DEVICE_NOT_SELECTED_INDEX) }
    val rememberPairScreenState = rememberConnectionScreenState(context, viewModel)
    val bluetoothEnableState by remember { derivedStateOf { viewModel.isBluetoothEnabled } }
    LaunchedEffect(key1 = bluetoothEnableState) {
        viewModel.handleBluetoothScanState(rememberPairScreenState.bluetoothAdapter)
    }

    LaunchedEffect(key1 = selectedIndexOfAvailableItem) {
        viewModel.handleTimeWarning(selectedIndexOfAvailableItem)
    }

    ComposableLifecycle { source, event ->
        if (event == Lifecycle.Event.ON_PAUSE) {
             viewmodel.stopScan()
        } else if (event == Lifecycle.Event.ON_RESUME) {
          viewModel.handleBluetoothScanState(rememberPairScreenState.bluetoothAdapter)
        }
    }
}

ComposableLifecycle个

@Composable
fun ComposableLifecycle(
    lifeCycleOwner: LifecycleOwner = LocalLifecycleOwner.current,
    onEvent: (LifecycleOwner, Lifecycle.Event) -> Unit
) {
    DisposableEffect(lifeCycleOwner) {
        val observer = LifecycleEventObserver { source, event ->
            onEvent(source, event)
        }
        lifeCycleOwner.lifecycle.addObserver(observer)
        onDispose {
            lifeCycleOwner.lifecycle.removeObserver(observer)
        }
    }
}

PairViewModel个

class PairViewModel : BaseViewModel() {

    companion object {
        private const val WARNING_PERIOD_IN_MILLES: Long = 60000 // For 1 minute scan
        const val DEVICE_NOT_SELECTED_INDEX = -1
    }

    var isBluetoothEnabled by mutableStateOf(false)
        private set

    private var job = Job()
        get() {
            if (field.isCancelled) field = Job()
            return field
        }

    fun startScan(adapter: BluetoothAdapter) = viewModelScope.launch {
        // start scan
    }

    fun stopScan(adapter: BluetoothAdapter) {
       // stop scan
    }


    fun handleBluetoothScanState(bluetoothAdapter: BluetoothAdapter) {
        if (isBluetoothEnabled) {
            startScan(bluetoothAdapter)
        } else {
            cancelTimeWarning()
            stopScan(bluetoothAdapter)
        }
    }


    fun handleTimeWarning(selectedIndexOfAvailableItem: Int) {
        if (selectedIndexOfAvailableItem == DEVICE_NOT_SELECTED_INDEX) {
            startTimeWarning()
        } else {
            cancelTimeWarning()
        }
    }

    fun startTimeWarning() {
        viewModelScope.launch(job) {
            delay(WARNING_PERIOD_IN_MILLES)
            // make event here
        }
    }

    internal fun cancelTimeWarning() {
        if (job.isActive) {
            job.cancel()
        }
        // make event here
    }
}

Note bluetoothEnableState是蓝牙ON和OFF，即分别是true和false.

当bluetooth状态改变为ON或OFF时，我正在使用LaunchedEffect收听bluetoothEnableState.这个很好用.现在问题出现了，

当活动开始时，在onResume和LaunchedEffect上调用viewModel.handleBluetoothScanState(rememberPairScreenState.bluetoothAdapter)两次.

2.当用户禁用蓝牙时，它的状态更改为false，他将转到onPause.在返回onResume之后，handleBluetoothScanState将呼叫并且还将蓝牙状态改变为true，然后再次呼叫LaunchedEffect.

我会解释更多关于第二种情况的细节

On Resume             Close App   Open App
Bluetooth disable ->  On Pause -> OnResume -> Bluetooth enable
      |                              |            |
     \ /                            \ /          \ /
Launcheffect                      function     Launcheffect 

所以我想防止调用双倍时间函数，有没有办法解决这个问题？谢谢