sealed class StateClass {
      data class StateNormal(val action: Int = ACTION_NONE) : StateClass()
      data class StatePreparing(val action: Int = ACTION_NONE) : StateClass()
      data class StateRecording(val action: Int = ACTION_NONE) : StateClass()
      data class StateWantCancel(val action: Int = ACTION_NONE) : StateClass()
}
private val recordLiveData = MutableLiveData<StateClass>()

recordLiveData.observe(context as LifecycleOwner) { state ->
            when (state) {
                is StateClass.StateNormal -> {
                    if (state.action == MotionEvent.ACTION_UP) {
                      ...
                    }
                }
                ...
            }        
            ...
}