Hello i am trying to implement JetPack datastore into my app by watching some tutorial i am newbie to koltin. I followed everything in this video : https://www.youtube.com/watch?v=0J5GXuGD61E&t=366s
UserManager.kt
class UserManager(context: Context) {
//Create the dataStore
private val dataStore = context.createDataStore(name = "user_prefs")
//Create some keys
companion object {
val USER_AGE_KEY = preferencesKey<String>("USER_AGE")
val USER_NAME_KEY = preferencesKey<String>("USER_NAME")
}
//Store user data
suspend fun storeUser(age: String, name: String) {
dataStore.edit {
it[USER_AGE_KEY] = age
it[USER_NAME_KEY] = name
}
}
//Create a name flow
val userNameFlow: Flow<String> = dataStore.data.map {
it[USER_NAME_KEY] ?: ""
}
//Create a name flow
val userAgeFlow: Flow<String> = dataStore.data.map {
it[USER_AGE_KEY] ?: ""
}
}
Class MainActivity.kt
class MainActivity : AppCompatActivity() {
lateinit var userManager: UserManager
var name = ""
var age = ""
var dataStoreEmail = ""
var dataStorePassword = ""
private fun saveData(email: String, password:String){
GlobalScope.launch {
userManager.storeUser(email,password)
}
}
private fun observeData() {
//Updates age
userManager.userAgeFlow.asLiveData().observe(this, {
age = it
dataStoreEmail = it.toString()
})
//Updates name
userManager.userNameFlow.asLiveData().observe(this, {
name = it
dataStorePassword= it.toString()
})
println("================================== " dataStoreEmail " ====================" dataStorePassword)
}
And when i try to access any of theese methods i get:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.myapp, PID: *
kotlin.UninitializedPropertyAccessException: lateinit property userManager has not been initialized
CodePudding user response:
As described in the error message, you have a lateinit
property that wasn't initialized:
lateinit var userManager: UserManager
You need to initialize it before use it as follows:
userManager = UserManager(this) // From MainActivity