这是我的UserManager.kt类,它具有保存和映射数据的功能,但如何创建一个函数来告诉我数据存储区是否有用户?
class UserManager(context: Context) {
private val dataStore = context.createDataStore(name = "user_prefs")
companion object {
val USER_NAME_KEY = preferencesKey<String>("USER_NAME")
val USER_NUMBER_KEY = preferencesKey<Int>("USER_NUMBER")
}
suspend fun storeUser(number: Int, name: String) {
dataStore.edit {
it[USER_NUMBER_KEY] = number
it[USER_NAME_KEY] = name
}
}
val userNumberFlow: Flow<Int> = dataStore.data.map {
it[USER_NUMBER_KEY] ?: 0
}
val userNameFlow: Flow<String> = dataStore.data.map {
it[USER_NAME_KEY] ?: ""
}
}
Run Code Online (Sandbox Code Playgroud) 这是我的导航主机
composable(
"${Screens.Start.route}/{tId}",
arguments = listOf(navArgument("tId") {
type = NavType.StringType
})
) {
StartScreen(viewModel, navController, it.arguments?.getString("tId") ?: "")
}
composable(
"${Screens.Timer.route}/{sId}",
arguments = listOf(navArgument("sId") {
type = NavType.StringType
})
) {
TimerScreen(viewModel, navController, it.arguments?.getString("tId") ?: "")
}
}
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我正在从主屏幕导航到“开始”屏幕,但没有从“开始”导航到“计时器屏幕”,我已经传递了从主屏幕获取的相同 ID。
这个主要可组合
@Composable
fun Main(task: CustomeTask, navController: NavController) {
Box(.clickable {
navController.navigate("${Screens.Start.route}/${task.pid.toString()}")
}
}
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开始画面
@Composable
fun StartScreen(viewModel: MainViewModel, navController: NavHostController, id : String) {
onclick{
navController.navigate("${Screens.Timer.route}/{$id}")
}
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当我单击按钮时应用程序崩溃并且错误如下
java.lang.NumberFormatException: For input string: "{11}"
at java.lang.Long.parseLong(Long.java:594)
at java.lang.Long.parseLong(Long.java:636)
at com.ashish.custometimer.ui.TimerScreenKt.TimerScreen(TimerScreen.kt:36)
at …Run Code Online (Sandbox Code Playgroud)