Observing and binding object Android MVVM

Question

How to observe object which is in ViewModel from View? Eg. I have a Class:

class MyClass {
var variable: Int = 0

fun increment() {
    variable += 1
}

In view model I have an instance of this class - MyClassObject. There is a TextView in Fragment and I want to bind it to the MyClassObject.variable

EDIT.

I made sth like this and it works but I think this isn't the best way to do it.

class GameState
{
    private val _variable = MutableLiveData<Int>()
    val variable: LiveData<Int>
        get() = _variable

    init
    {
        _variable.value = 0
    }

    fun increment()
    {
        _variable.value = _variable.value!!.plus(1)
    }
}

ViewModel:

class GameViewModel : ViewModel()
{

    private val _gameState: GameState = GameState()
    val gameState: GameState
        get() = _gameState


    fun imgClick()
    {
        gameState.increment()
    }
}

View:

       <TextView
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:text="@{gameViewModel.gameState.variable.toString()}" />

       <ImageView
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:onClick="@{() -> gameViewModel.imgClick()}"

refer this link: to create observer class and use it with livedata https://stackoverflow.com/questions/48020377/livedata-update-on-object-field-change — Nataraj KR, Apr 08 '20 at 11:09

score 0 · Answer 1 · answered Apr 08 '20 at 11:57

0

Do you know LiveData?, You can use LiveData component included in Jetpack that's for observing in diff layers such as Repository or ViewModel to other layers.

answered Apr 08 '20 at 11:57

ImanX

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Observing and binding object Android MVVM

1 Answers1