Parent DataHolder for easy implementation of DataHolder for Activities.

AacMviDH.kt

open class AacMviDH<STATE, EFFECT> {

    private val _states: MutableLiveData<STATE> = MutableLiveData()
    val stateLiveData: LiveData<STATE>
        get() = _states

    private var _state: STATE? = null
    var state: STATE
        get() = _state
            ?: throw UninitializedPropertyAccessException("\"state\" was queried before being initialized")
        set(value) {
            Log.d(TAG, "setting viewState : $value")
            _state = value
            _states.value = value
        }

    private val _effects: SingleLiveEvent<EFFECT> = SingleLiveEvent()
    val effectLiveData: SingleLiveEvent<EFFECT>
        get() = _effects
    var effect: EFFECT? = null
        set(value) {
            Log.d(TAG, "setting viewEffect : $value")
            field = value
            _effects.value = value
        }

    fun onCleared() {
        _state = null
    }
}