I have a viewmodel for a fragment with a search functionality. I made use of Coroutines to fetch from the API and then set the MediatorLiveData value with the result, although the list of objects are reflected on my RecyclerView. When I try to access the MediatorLiveData value with liveData.value
, it returns null. I've tried debugging it but despite displaying the list of objects, I can't really access the value of the livedata in the ViewModel
class SearchViewModel @Inject constructor(private val mutwitsRepo: MutwitsRepo) : BaseViewModel() {
val query = MutableLiveData<String>()
private val _isLoading = MutableLiveData<Boolean>()
val isLoading: LiveData<Boolean> = _isLoading
private val _users = MediatorLiveData<List<User>>()
val users: LiveData<List<User>> = _users
private var queryTextChangedJob: Job? = null
init {
_users.addSource(query) { queryStr ->
if (queryStr.isNullOrEmpty()) _users.value = emptyList()
else searchUsers(queryStr)
}
}
fun searchUsers(query: String) {
_isLoading.value = true
queryTextChangedJob?.cancel()
queryTextChangedJob = viewModelScope.launch {
delay(300)
_users.value = mutwitsRepo.searchUsers(query)
_isLoading.value = false
}
}
fun selectUser(user: User) {
val temp = _users.value
temp?.find { it.id_str == user.id_str }?.toggleSelected()
_users.value = temp
}
override fun onCleared() {
super.onCleared()
queryTextChangedJob?.cancel()
}
}
suspend fun searchUsers(query: String): List<User> = withContext(Dispatchers.IO) {
return@withContext twitterService.searchUsers(query)
My codes are shown above, I've been stuck for days now and any help would be much appreciated! }
Apparently this problem was caused by the injection of ViewModel
in my adapter. I injected my viewmodel in my adapter with dagger and set the button's onClickListener
with the function selectUser()
. I extracted the setting of clickListener
to my fragment and it worked.