理想の筋トレアプリが無かったので自分で作る ①アイデア＋WearOS開発 #Kotlin – Qiita

@Composable
fun HeartRateMonitorUI(viewModel: HeartRateViewModel) {
    val context = LocalContext.current
    val heartRate = viewModel.heartRate.value
    val alertMessage = viewModel.alertMessage.value

    val heartRateInt = heartRate.toIntOrNull() ?: 0
    val heartColor = when {
        heartRateInt >= 130 -> Color.Red
        heartRateInt >= 120 -> Color.Yellow
        else -> Color.White
    }

    val isRunning = remember { mutableStateOf(false) }
    val elapsedTime = remember { mutableStateOf(0L) }

    LaunchedEffect(isRunning.value) {
        while (isRunning.value) {
            delay(1000L)
            elapsedTime.value += 1000L
        }
    }

    val formattedTime = remember(elapsedTime.value) {
        val seconds = (elapsedTime.value / 1000) % 60
        val minutes = (elapsedTime.value / (1000 * 60)) % 60
        val hours = (elapsedTime.value / (1000 * 60 * 60))
        String.format("%02d:%02d:%02d", hours, minutes, seconds)
    }

    Surface(
        modifier = Modifier.fillMaxSize(),
        color = Color(0xFF101010)
    ) {
        Column(
            modifier = Modifier
                .fillMaxSize()
                .padding(24.dp),
            verticalArrangement = Arrangement.Center,
            horizontalAlignment = Alignment.CenterHorizontally
        ) {
            Text(text = "$heartRate bpm", fontSize = 20.sp, color = heartColor)

            Spacer(modifier = Modifier.height(8.dp))

            HorizontalDivider(thickness = 1.dp, color = Color.Gray)

            Spacer(modifier = Modifier.height(16.dp))

            Text(
                text = formattedTime,
                style = MaterialTheme.typography.headlineMedium,
                color = Color.White
            )

            Spacer(modifier = Modifier.height(16.dp))

            Row {
                IconButton(onClick = { isRunning.value = !isRunning.value }) {
                    Icon(
                        imageVector = if (isRunning.value) Icons.Filled.Pause else Icons.Filled.PlayArrow,
                        contentDescription = null,
                        tint = Color.White,
                        modifier = Modifier.size(48.dp)
                    )
                }

                Spacer(modifier = Modifier.width(8.dp))

                IconButton(onClick = {
                    isRunning.value = false
                    elapsedTime.value = 0L
                }) {
                    Icon(
                        imageVector = Icons.Filled.Replay,
                        contentDescription = "reset",
                        tint = Color.White,
                        modifier = Modifier.size(48.dp)
                    )
                }
            }

            if (alertMessage != null) {
                HeartRateAlertDialog(message = alertMessage) {
                    viewModel.clearAlert()
                }
            }
        }
    }
}

@SuppressLint("ServiceCast")
@Composable
fun HeartRateAlertDialog(message: String, onDismiss: () -> Unit) {
    val context = LocalContext.current

    // バイブレーション効果
    LaunchedEffect(message) {
        val vibrator = context.getSystemService(Context.VIBRATOR_SERVICE) as Vibrator
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            vibrator.vibrate(VibrationEffect.createOneShot(500, VibrationEffect.DEFAULT_AMPLITUDE))
        } else {
            @Suppress("DEPRECATION")
            vibrator.vibrate(500)
        }
    }

    Box(
        modifier = Modifier
            .fillMaxSize()
            .background(Color.Black),
        contentAlignment = Alignment.Center
    ) {
        AlertDialog(
            onDismissRequest = onDismiss,
            confirmButton = {
                Column(
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(bottom = 8.dp),
                    horizontalAlignment = Alignment.CenterHorizontally
                ) {
                    Button(
                        onClick = onDismiss,
                        colors = ButtonDefaults.buttonColors(containerColor = Color.White),
                        modifier = Modifier.height(32.dp)
                    ) {
                        Text("OK", fontSize = 12.sp, color = Color.Black)
                    }
                }
            },
            text = {
                Text(
                    text = message,
                    color = Color.White,
                    fontSize = 15.sp,
                    lineHeight = 20.sp,
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(horizontal = 8.dp, vertical = 4.dp),
                    textAlign = TextAlign.Center
                )
            },
            containerColor = Color.Black,
            tonalElevation = 0.dp,
            modifier = Modifier
                .fillMaxSize()
                .padding(horizontal = 12.dp, vertical = 24.dp),
            shape = RoundedCornerShape(0.dp)
        )
    }
}