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How to make recyclerview populate after response finishes

I'm having a problem with "UninitializedPropertyAccessException", I believe it's because the recyclerview is trying to be populated before the response finishes the process, does anyone know how I can solve it? P.S: This is causing my published app to crash, but in the emulator it works normally
TibiaApiService:
class TibiaApiService {
companion object {
private const val BASE_URL = "https://api.tibiadata.com"
private var retrofit: Retrofit? = null
fun getInstance(): Retrofit {
val okHttpClient: OkHttpClient = OkHttpClient.Builder()
.readTimeout(60, TimeUnit.SECONDS)
.connectTimeout(60, TimeUnit.SECONDS)
.build()
if (retrofit == null) {
retrofit = Retrofit.Builder()
.baseUrl(BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.client(okHttpClient)
.build()
}
return retrofit!!
}
}}
NewsArchiveFragment:
class NewsArchiveFragment : Fragment() {
private lateinit var binding: FragmentNewsArchiveBinding
private lateinit var newsModel: List<NewsModel>
private lateinit var newsFromId: NewsFromIdModel
private lateinit var progressDialog: ProgressDialog
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View {
binding = FragmentNewsArchiveBinding.inflate(layoutInflater, container, false)
progressDialog = ProgressDialog(activity)
getNews()
return binding.root
}
private fun getNews() = with(binding) {
try {
progressDialog.setMessage("Loading...")
progressDialog.show()
val apiService = TibiaApiService.getInstance().create(TibiaApiInterface::class.java)
apiService.getNewsArchive().enqueue(object : retrofit2.Callback<NewsResponse>,
NewsArchiveAdapter.ClickNews {
override fun onResponse(
call: Call<NewsResponse>,
response: Response<NewsResponse>
) {
if(response.isSuccessful) {
newsModel = response.body()!!.news
populateRV(newsModel, this)
}
}
override fun onFailure(call: Call<NewsResponse>, t: Throwable) {
progressDialog.dismiss()
Snackbar.make(root, t.message.toString(), Snackbar.LENGTH_LONG)
.show()
}
override fun clickNews(news: NewsModel) {
loadCompleteNews(news.id)
}
})
} catch (e: SocketTimeoutException) {
Snackbar.make(root, e.message.toString(), Snackbar.LENGTH_LONG)
.show()
}
}
private fun populateRV(
newsModel: List<NewsModel>,
clickNews: NewsArchiveAdapter. ClickNews
) = with(binding) {
rvNews.layoutManager = LinearLayoutManager(activity)
rvNews.setHasFixedSize(true)
rvNews.adapter = NewsArchiveAdapter(newsModel, clickNews)
rvNews.viewTreeObserver.addOnGlobalLayoutListener {
progressDialog.dismiss()
}
}
private fun loadCompleteNews(id: Int) = with(binding) {
val apiService = TibiaApiService.getInstance().create(TibiaApiInterface::class.java)
apiService.getNewsArchiveFromId(id)
.enqueue(object : retrofit2.Callback<NewsFromIdResponse> {
override fun onResponse(
call: Call<NewsFromIdResponse>,
response: Response<NewsFromIdResponse>
) {
newsFromId = response.body()!!.newsFromId
onShowDialog(newsFromId)
}
override fun onFailure(call: Call<NewsFromIdResponse>, t: Throwable) {
Snackbar.make(root, t.message.toString(), Snackbar.LENGTH_LONG).show()
}
})
}
private fun onShowDialog(newsFromId: NewsFromIdModel) {
MaterialAlertDialogBuilder(requireContext())
.setTitle(newsFromId.date)
.setMessage(newsFromId.content)
.setNegativeButton(getString(R.string.close_dialog)) { dialog, _ ->
dialog.dismiss()
}
.show()
}}
NewsArchiveAdapter:
class NewsArchiveAdapter(
private val news: List<NewsModel>,
private val clickNews: ClickNews
) : RecyclerView.Adapter<NewsArchiveAdapter.ViewHolder>() {
interface ClickNews{
fun clickNews(news: NewsModel)
}
inner class ViewHolder(val binding: RvNewsListBinding) :
RecyclerView.ViewHolder(binding.root)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
return ViewHolder(
RvNewsListBinding.inflate(
LayoutInflater.from(parent.context), parent, false
)
)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val _news = news[position]
holder.binding.apply {
txtNewsNews.text = _news.news
txtNewsDate.text = _news.date
if (position % 2 == 0) {
cardViewNews.setBackgroundColor(
root.resources.getColor(R.color.very_light_brown)
)
} else {
cardViewNews.setBackgroundColor(
root.resources.getColor(R.color.light_brown)
)
}
cardViewNews.setOnClickListener { clickNews.clickNews(_news) }
}
}
override fun getItemCount(): Int = news.size}

RecyclerView doesn't appear in a Fragment

Why doesn't RecyclerView appear in my fragment? I've added recyclerview adapter in the fragment, but it still didn't appear. Here are the codes:
FollowersFragment.kt
class FollowersFragment : Fragment() {
private lateinit var binding: FragmentFollowersBinding
companion object {
private const val TAG = "FollowersFragment"
const val ARG_NAME = "userName"
}
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
return inflater.inflate(R.layout.fragment_followers, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
binding = FragmentFollowersBinding.inflate(layoutInflater)
val username = arguments?.getString(ARG_NAME)
val layoutManager = LinearLayoutManager(requireActivity())
binding.rvFollowers.layoutManager = layoutManager
val itemDecoration = DividerItemDecoration(requireActivity(), layoutManager.orientation)
binding.rvFollowers.addItemDecoration(itemDecoration)
val client = ApiConfig.getApiService().getFollowers(username.toString(),"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")
client.enqueue(object : Callback<List<FollowsResponseItem>> {
override fun onResponse(
call: Call<List<FollowsResponseItem>>,
response: Response<List<FollowsResponseItem>>
) {
if(response.isSuccessful){
val responseBody = response.body()
if(responseBody!=null){
Log.d(TAG,responseBody.toString())
setUserData(responseBody)
}else{
Log.e(TAG,"onFailure: ${response.message()}")
}
}
}
override fun onFailure(call: Call<List<FollowsResponseItem>>, t: Throwable) {
Log.e(TAG, "onFailure: ${t.message}")
}
})
}
fun setUserData(item: List<FollowsResponseItem>){
val listUser = ArrayList<UserResponse>()
val executor = Executors.newSingleThreadExecutor()
executor.execute {
try {
for (i in 0..item.size-1) {
if(item.size>5 && i>5){
break
}
val client = ApiConfig.getApiService()
.getUser(item.get(i).login, "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")
client.enqueue(object : Callback<UserResponse> {
override fun onResponse(
call: Call<UserResponse>,
response: Response<UserResponse>
) {
if (response.isSuccessful) {
val responseBody = response.body()
if (responseBody != null) {
listUser.add(responseBody)
if(i==4 || item.get(i).login.equals(item.get(item.size-1).login)){
Log.d(TAG,"user : $listUser")
val adapter = ListUserAdapter(listUser)
binding.rvFollowers.adapter = adapter
Log.d(TAG,adapter.toString())
adapter.setOnItemClickCallback(object: ListUserAdapter.OnItemClickCallback{
override fun onItemClicked(data: UserParcelable) {
showSelectedUser(data)
}
})
}
} else {
Log.e(TAG, "onFailure: ${response.message()}")
}
}
}
override fun onFailure(call: Call<UserResponse>, t: Throwable) {
Log.e(TAG, "onFailure: ${t.message}")
}
})
}
} catch(e: InterruptedException) {
e.printStackTrace()
}
}
}
private fun showSelectedUser(data: UserParcelable) {
}
}
DetailActivity.kt
class DetailActivity : AppCompatActivity() {
private lateinit var binding: ActivityDetailBinding
private var getUserName: String ="sidiqpermana"
companion object{
const val EXTRA_DATA = "extra_data"
#StringRes
private val TAB_TITLES = intArrayOf(
R.string.tab_text_1,
R.string.tab_text_2
)
}
#SuppressLint("SetTextI18n")
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
supportActionBar?.hide()
binding = ActivityDetailBinding.inflate(layoutInflater)
setContentView(binding.root)
val data = intent.getParcelableExtra<UserParcelable>(EXTRA_DATA) as UserParcelable
val sectionsPagerAdapter = SectionsPagerAdapter(this)
val viewPager: ViewPager2 = binding.viewPager
viewPager.adapter = sectionsPagerAdapter
val tabs: TabLayout = binding.tabs
sectionsPagerAdapter.userName = data.login
TabLayoutMediator(tabs,viewPager){ tab, position ->
tab.text = resources.getString(TAB_TITLES[position])
}.attach()
getUserName = data.login
showInfo(data)
}
fun getUserName() : String{
return getUserName
}
#SuppressLint("SetTextI18n")
private fun showInfo(data: UserParcelable){
Glide.with(this#DetailActivity)
.load(data.avatar_url)
.into(binding.detailPp)
if(data.name.equals("null")) binding.detailName.setText("No Name") else binding.detailName.setText(data.name)
binding.detailUsername.setText(data.login)
if(data.bio.equals("null")) binding.detailBio.setText("No Name") else binding.detailBio.setText(data.bio)
binding.detailFollowers.setText("${data.followers} Followers")
binding.detailFollowings.setText("${data.following} Following")
if(data.location.equals("null")) binding.detailLocation.setText("No Location") else binding.detailLocation.setText(data.location)
}
}
ListUserAdapter.kt (RecyclerView Adapter)
class ListUserAdapter (private val listUser: ArrayList<UserResponse>) : RecyclerView.Adapter<ListUserAdapter.ListViewHolder>() {
private lateinit var onItemClickCallback: OnItemClickCallback
fun setOnItemClickCallback(onItemClickCallback: OnItemClickCallback){
this.onItemClickCallback = onItemClickCallback
}
class ListViewHolder(var binding: ItemUsersRowBinding) : RecyclerView.ViewHolder(binding.root) {
}
override fun onCreateViewHolder(viewGroup: ViewGroup, viewType: Int): ListViewHolder {
val binding = ItemUsersRowBinding.inflate(LayoutInflater.from(viewGroup.context),viewGroup,false)
return ListViewHolder(binding)
}
#SuppressLint("SetTextI18n")
override fun onBindViewHolder(holder: ListViewHolder, position: Int) {
var (followers,avatar_url,following, name,bio, location, login) = listUser[position]
name = name ?: "No Name"
bio = bio ?: "No Bio"
location = location?: "No Location"
holder.apply {
Glide.with(itemView.getContext())
.load(avatar_url)
.into(binding.photoProfile)
binding.profileName.setText(name.toString())
binding.username.setText(login)
binding.followers.setText("$following Followers")
binding.followings.setText("$following Followings")
binding.location.setText(location.toString())
val detailUser = UserParcelable(followers,avatar_url,following,
name.toString(), bio.toString(), location.toString(), login)
itemView.setOnClickListener{ onItemClickCallback.onItemClicked(detailUser)}
}
}
override fun getItemCount(): Int {
return listUser.size
}
interface OnItemClickCallback {
fun onItemClicked(data: UserParcelable)
}
}
Help me solve this problem please.

There is no need to initialize adapter every time you want to update the list. Either make your ListUserAdapter extend ListAdapter and than use adapter.submitList(listUser) or if you want to extend RecyclerView.Adapter as you do, you can do the following :
class ListUserAdapter () : RecyclerView.Adapter<ListUserAdapter.ListViewHolder>() {
private val listUser: List<UserResponse>
fun submitList(newList: List<UserResponse>) {
listUser = newList
notifyDataSetChanged()
}
override fun onBindViewHolder(holder: ListViewHolder, position: Int) {
val listItem = listUser[position]
...
}
override fun getItemCount(): Int {
return listUser.size
}
}
I suggest you go with ListAdapter. Check if Log.d(TAG,"user : $listUser") is printed, if it is and listUser is not empty than call adapter.submitList(listUser) and RV should be populated.

You have missed to notify adapter about the changes, So after
binding.rvFollowers.adapter = adapter call adapter.notifyDataSetChanged()

Clicking on Recyclerview item has a late item

I have an application using databinding, livedata, room, kotlin koroutines, viewmodel, retrofit and koin. I have one activity, and two fragments.
UserListFragment: Show in a recyclerview a list of user items.
UserFullProfileFragment: Show the user item detail.
When the application is running, an external API is called to retrieve a list of users and display it in a recyclerview. Then, if I click on one item, an external API is called to get the detail of the current user whith its ID.
The problem is when I click on one item at the first, everything is going well but for following items, this is the detail of previous item which is displayed and so on and so forth.
Any ideas ?
UserRepository:
class UserRepositoryImpl (private val userApi: UserApi, private val userDao: UserDao, private val networkStateManager: NetworkStateManager) : UserRepository {
override suspend fun getUserList(): Result<List<UserListItem>> {
if (networkStateManager.hasNetWorkConnection()) {
return try {
// get user list from user API
val response = userApi.getUserList()
if (response.isSuccessful) {
Log.d("REPO", "get users from api")
response.body()?.let { userResponse ->
Log.d("REPO", "response:$response")
val userList = userResponse.data
// convert user API object to user entity
val entities = userList.map { it.toUserEntity() }
// save user list in database
withContext(Dispatchers.IO) { userDao.addUsers(entities) }
// convert user entity to user model
val userItemList = entities.map { it.toUserListItem() }
return Result.Success(userItemList)
} ?: handleFailure(response)
} else {
handleFailure(response)
}
} catch (e: Exception) {
return Result.Failure(e, e.localizedMessage)
}
} else {
// get user list from database if no network
val data = withContext(Dispatchers.IO) { userDao.findAllUsers() }
return if (data.isNotEmpty()) {
Log.d("REPO", "get users from db")
val userItemList = data.map { it.toUserListItem() }
Result.Success(userItemList)
} else {
Result.Failure(Exception("error"), "no network connection")
}
}
}
override suspend fun getUserFullProfile(userId: String): Result<UserFullProfile> {
if (networkStateManager.hasNetWorkConnection()) {
return try {
// get user from user API
val response = userApi.getUserFullProfile(userId)
if (response.isSuccessful) {
Log.d("REPO", "get users from api")
response.body()?.let { userResponse ->
Log.d("REPO", "response:$userResponse")
// convert user API object to user entity
val userEntity = userResponse.toUserEntity()
// save user data in database
withContext(Dispatchers.IO) { userDao.addUserFullProfile(userEntity) }
// convert user entity to user model
val user = userEntity.toUserFullProfile()
return Result.Success(user)
} ?: handleFailure(response)
} else {
handleFailure(response)
}
} catch (e: Exception) {
return Result.Failure(e, e.localizedMessage)
}
} else {
// get user from database if no network
val data = withContext(Dispatchers.IO) { userDao.getUserById(userId) }
return if (data != null) {
Log.d("REPO", "get users from db")
val user = data.toUserFullProfile()
Result.Success(user)
} else {
Result.Failure(Exception("error"), "no network connection")
}
}
}
UserViewModel:
getUserList and getUserFullProfile are use cases which call the repository
class UserViewModel (private val getUserList: GetUserList, private val getUserFullProfile: GetUserFullProfile) : ViewModel() {
val userList = MutableLiveData<List<UserListItem>>()
val userFullProfile = MutableLiveData<UserFullProfile>()
fun getUserList() {
viewModelScope.launch {
when (val result = getUserList.getUserList()) {
is Result.Success -> userList.value = result.successData
is Result.Failure -> result.exception.localizedMessage
}
}
}
fun getUserFullProfile(userId: String) {
viewModelScope.launch {
when (val result = getUserFullProfile.getUserFullProfile(userId)) {
is Result.Success -> userFullProfile.value = result.successData
is Result.Failure -> result.exception.localizedMessage
}
}
}
UserRecyclerAdaper:
class UserRecyclerAdapter(private val context: Context?, val clickListener: UserClickListener) : RecyclerView.Adapter<UserRecyclerAdapter.UserViewHolder>() {
var userList : List<UserListItem> = ArrayList()
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): UserViewHolder {
val inflatedView: UserItemBinding = DataBindingUtil.inflate(LayoutInflater.from(parent.context), R.layout.user_item, parent, false)
return UserViewHolder(inflatedView)
}
override fun onBindViewHolder(holder: UserViewHolder, position: Int) {
holder.bindUser(position)
}
override fun getItemCount() = userList.size
fun setUsers(users: List<UserListItem>) {
this.userList = users
notifyDataSetChanged()
}
inner class UserViewHolder(private val v: UserItemBinding) : RecyclerView.ViewHolder(v.root) {
fun bindUser(position: Int) {
val item = userList[position]
Log.d("ADAPTER", item.toString())
v.user = item
Picasso.get()
.load(item.picture)
.placeholder(R.drawable.ic_launcher_foreground)
.error(R.drawable.ic_launcher_background)
.into(v.picture)
v.userClickInterface = clickListener
v.root.setOnClickListener {
clickListener.onItemClick(item)
}
}
}
UserListFragment:
class UserListFragment : Fragment(), UserClickListener {
private val userViewModel by viewModel<UserViewModel>()
private lateinit var userAdapter: UserRecyclerAdapter
private lateinit var viewDataBinding: FragmentUserListBinding
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
viewDataBinding = DataBindingUtil.inflate(inflater, R.layout.fragment_user_list, container, false)
viewDataBinding.lifecycleOwner = this
return viewDataBinding.root
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
recyclerView.layoutManager = LinearLayoutManager(activity, LinearLayoutManager.VERTICAL, false)
userAdapter = UserRecyclerAdapter(context, this)
recyclerView.adapter = userAdapter
recyclerView.isNestedScrollingEnabled = false
viewDataBinding.viewModel = userViewModel
userViewModel.getUserList()
userViewModel.userList.observe(viewLifecycleOwner, { userList ->
if (userList.isNotEmpty() && userList != null) {
userAdapter.setUsers(userList)
}
})
}
override fun onItemClick(user: UserListItem) {
Log.d("FRAGMENT", user.toString())
userViewModel.getUserFullProfile(user.id)
userViewModel.userFullProfile.observe(viewLifecycleOwner, { userFullProfile ->
Log.d("UFP", userFullProfile.toString())
if (userFullProfile != null) {
(activity as MainActivity).replaceFragment(UserFullProfileFragment.newInstance(userFullProfile),
R.id.fragment_layout, "userFullProfile")
}
})
}
UserFullProfileFragment:
class UserFullProfileFragment : Fragment() {
companion object {
#JvmStatic
fun newInstance(user: UserFullProfile) = UserFullProfileFragment().apply {
arguments = Bundle().apply {
putParcelable("user", user)
}
}
}
private var user: UserFullProfile? = null
private lateinit var mViewDataBinding: FragmentUserFullProfileBinding
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
mViewDataBinding.user = user
notify()
Picasso.get()
.load(mViewDataBinding.user?.picture)
.placeholder(R.drawable.ic_launcher_foreground)
.error(R.drawable.ic_launcher_background)
.into(mViewDataBinding.picture)
val dateOfBirth = parseDate(mViewDataBinding.user?.dateOfBirth)
mViewDataBinding.dateOfBirth.text = dateOfBirth
val registerDate = parseDate(mViewDataBinding.user?.registerDate)
mViewDataBinding.registerDate.text = registerDate
}
override fun onAttach(context: Context) {
super.onAttach(context)
user = arguments?.getParcelable("user")
Log.d("APP", user.toString())
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
mViewDataBinding = DataBindingUtil.inflate(inflater,
R.layout.fragment_user_full_profile, container, false)
mViewDataBinding.lifecycleOwner = this
return mViewDataBinding.root
}
Thank you :)

Finally, I found a solution :
I pass the user id argment from UserListFragment to UserFullProfileFragment instead of the current user object and I call the external API to get the current user in the UserFullProfileFragment.
This is the final code:
UserListFragment:
override fun onItemClick(user: UserListItem) {
val action = UserListFragmentDirections.actionUserListFragmentToUserFullProfileFragment(user.id)
findNavController().navigate(action)
}
UserFullProfileFragment:
class UserFullProfileFragment : Fragment() {
private lateinit var userID: String
private var mViewDataBinding: FragmentUserFullProfileBinding? = null
private val binding get() = mViewDataBinding!!
private val userViewModel by viewModel<UserViewModel>()
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
binding.viewModel = userViewModel
userID = UserFullProfileFragmentArgs.fromBundle(requireArguments()).userArgs
userViewModel.getUserFullProfile(userID)
userViewModel.userFullProfile.observe(viewLifecycleOwner, { userFullProfile ->
if (userFullProfile != null) {
binding.user = userFullProfile
Picasso.get()
.load(binding.user?.picture)
.placeholder(R.drawable.ic_launcher_foreground)
.error(R.drawable.ic_launcher_background)
.into(binding.picture)
val dateOfBirth = parseDate(binding.user?.dateOfBirth)
binding.dateOfBirth.text = dateOfBirth
val registerDate = parseDate(binding.user?.registerDate)
binding.registerDate.text = registerDate
}
})
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
mViewDataBinding = DataBindingUtil.inflate(inflater,
R.layout.fragment_user_full_profile, container, false)
binding.lifecycleOwner = this
return binding.root
}
override fun onDestroyView() {
super.onDestroyView()
mViewDataBinding = null
}
}

parse JSON object using retrofit in kotlin

I am trying to show json data using retrofit library in kotlin
This is my Json:
[
{
"login": "mojombo",
"id": 1,
},
{
"login": "defunkt",
"id": 2,
}
]
My Main activity
call.enqueue(object : Callback<UserResponse> {
override fun onResponse(call: Call<UserResponse>, response: Response<UserResponse>) {
Log.e("list","list")
val countrylist = response.body()
for (size in response.body()) {
System.out.println(size.toString())
}
// var listOfMovies: List<UserResponse> = response.body()?.results!!
// myCustomAdapter = UserListAdapter(applicationContext, listOfMovies)
// recyclerView.setAdapter(myCustomAdapter)
progressBar.visibility = View.GONE
}
override fun onFailure(call: Call<UserResponse>?, t: Throwable?) {
progressBar.visibility = View.GONE
Log.e("list", t.toString())
}
})

This an app that I build in kotlin using retrofit and rxjava in the best way possible using a test API.
Model
data class Post( val userID:Int, val title:String, val body: String)
Retrofit Package
IMyApi interface
interface IMyApi {
#get:GET("posts")
val posts: Observable<List<Post>>
}
RetrofitClient Object class
object RetrofitClient {
val instance: Retrofit by lazy {
Retrofit.Builder()
.baseUrl("https://jsonplaceholder.typicode.com/")
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.addConverterFactory(GsonConverterFactory.create())
.build()
}
}
Adapter Package
PostAdapter class
class PostAdapter(private val context: Context, private val postList: List<Post>)
:RecyclerView.Adapter<PostViewHolder>()
{
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int):
PostViewHolder {
val itemView = LayoutInflater.from(parent.context)
.inflate(R.layout.post_item, parent, false)
return PostViewHolder(itemView)
}
override fun getItemCount(): Int {
return postList.size
}
override fun onBindViewHolder(holder: PostViewHolder, position: Int)
{
holder.userId.text = postList[position].userID.toString()
holder.title.text = postList[position].title
holder.body.text = StringBuilder(postList[position].body.substring(0,20))
.append("...").toString()
}
}
PostViewHolder class
class PostViewHolder(itemView: View):RecyclerView.ViewHolder(itemView) {
var userId = itemView.txtID
var title = itemView.txtTitle
var body = itemView.txtBody
}
MainActivity
class MainActivity : AppCompatActivity() {
private lateinit var jsonApi: IMyApi
private var compositeDisposable: CompositeDisposable = CompositeDisposable()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// Init api
val retrofit = RetrofitClient.instance
jsonApi = retrofit.create(IMyApi::class.java)
// View
recycler_posts.layoutManager = LinearLayoutManager(this)
recycler_posts.setHasFixedSize(true)
fetchData()
}
private fun fetchData() {
compositeDisposable.add(jsonApi.posts
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe { posts->displayData(posts)})
}
private fun displayData(posts: List<Post>?) {
val adapter = PostAdapter(this, posts!!)
recycler_posts.adapter = adapter
}
}
Using this as displayed above should help you solve your issue hopefully. Also when in the code you come across "recycler_posts". This is a id to the recycler added in activity_main. If you need me to include that let me know

That's what we have on our app
object GetFAQsAPI {
private val LOG_TAG = GetFAQsAPI.javaClass.simpleName
interface ThisCallback {
fun onSuccess(getFAQs: GetFAQs)
fun onFailure(failureMessage: String)
fun onError(errorMessage: String)
}
/* POST */
fun postData(jo: JsonObject, callback: GetFAQsAPI.ThisCallback) {
val call = Service.getService().get_faqs(jo)
call.enqueue(object : Callback<JsonObject> {
override fun onResponse(call: Call<JsonObject>, response: Response<JsonObject>) {
//Log.e(LOG_TAG, response.body().toString());
try {
if (response.body()?.get("success")!!.asBoolean) {
val gson = GsonBuilder().setPrettyPrinting().create()
val getFAQs = gson.fromJson(response.body(), GetFAQs::class.java)
callback.onSuccess(getFAQs)
} else {
Log.e(LOG_TAG, "else")
val error = response.body()!!.get("err").asString
callback.onError(error)
}
} catch (e: Exception) {
Log.e(LOG_TAG, "exception" + e.localizedMessage)
callback.onFailure(e.message!!)
}
}
override fun onFailure(call: Call<JsonObject>, t: Throwable) {
Log.e(LOG_TAG, "onFailure: " + t.message)
callback.onFailure(t.message!!)
}
})
}
}
That's how we call it from our fragment - getFAQs is the object parsed.
private fun getFAQsAPI() {
showLoading(true)
val jo = JsonObject().apply {
addProperty("faq_category", "admin")
}
GetFAQsAPI.postData(jo, object : GetFAQsAPI.ThisCallback {
override fun onSuccess(getFAQs: GetFAQs) {
Log.i(LOG_TAG, "onSuccess")
showLoading(false)
updateUI(getFAQs)
}
override fun onFailure(failureMessage: String) {
Log.e(LOG_TAG, failureMessage)
}
override fun onError(errorMessage: String) {
Log.e(LOG_TAG, errorMessage)
}
})
}
Hope that helps.

search in a recyclerview

i have a fragment that have a recyclerview i'm trying to use setOnQueryTextListener to search some specific data and display the new data instead of the old one
this is my Fragmenttask.kt file
class Fragmenttask : Fragment(), SwipeRefreshLayout.OnRefreshListener {
private var mListener: OnFragmentInteractionListener? = null
private var mSwipeRefreshLayout: SwipeRefreshLayout? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
}
override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View? {
//container!!.removeAllViews()
setHasOptionsMenu(true)
val CustumViewtask = inflater!!.inflate(R.layout.fragment_fragmenttask, container, false)
val taskMainRV = CustumViewtask.findViewById(R.id.recyclerView_main) as RecyclerView
//taskMainRV.setBackgroundColor(Color.BLUE)
taskMainRV.layoutManager = LinearLayoutManager(context)
//recyclerView_main.adapter = MainAdapter()
fetchJson(taskMainRV)
return CustumViewtask
}
override fun onRefresh() {
Toast.makeText(context, "تم التحميل بنجاح والحمد لله", Toast.LENGTH_LONG).show()
}
override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
inflater.inflate(R.menu.menu_user, menu)
val searchItem = menu.findItem(R.id.action_search)
val searchView = MenuItemCompat.getActionView(searchItem) as SearchView
searchView.queryHint = "أكتب كلمة بحث ..."
searchView.setOnQueryTextListener(object : SearchView.OnQueryTextListener {
override fun onQueryTextChange(q: String): Boolean {
println("my serch : $q")
//fetchJson(taskMainRV)
//adaptertask?.notifyDataSetChanged()
//notifyDataSetChanged
println("mohamed 78797987897987987987987987987987987987897")
return false
}
override fun onQueryTextSubmit(q: String): Boolean {
println("my serch : $q")
println("mohamed 78797987897987987987987987987987987987897**************")
return false
}
})
//searchView.setOnQueryTextListener(this)
//https://stackoverflow.com/questions/30398247/how-to-filter-a-recyclerview-with-a-searchview?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa
}
fun onQueryTextChange(query: String): Boolean {
// Here is where we are going to implement the filter logic
return false
}
fun onQueryTextSubmit(query: String): Boolean {
return false
}
fun fetchJson(RSV: RecyclerView) {
//SharedPreferences
val MY_APP_INFO: String = "UserInfo"
val prefs = activity.getSharedPreferences(MY_APP_INFO, AppCompatActivity.MODE_PRIVATE)
val LoggedUserId = prefs.getString("UserId", null)
var serchqury = arguments.getString("serchqury")
if(serchqury.isNullOrEmpty()){
serchqury = ""
}
println(serchqury+" ------------**/*/*/*/*/*/*/*/*/*/ ")
println("your code is : $LoggedUserId")
println("Attempting to Fetch JSON")
val url = "http://www.deraah-rs.com/1mahamatonline/html/Restful/get_tasks.php"
val client = OkHttpClient()
val formBody = FormBody.Builder().add("UserId", LoggedUserId)
.add("serchqury", serchqury).build()
val request = Request.Builder().url(url)
.post(formBody)
.build()
client.newCall(request).enqueue(object: Callback {
override fun onResponse(call: Call?, response: Response?) {
val body = response?.body()?.string()
println("mohamed : $body")
val gson = GsonBuilder().create()
val tasksfeed = gson.fromJson(body, M_tasksFeed::class.java)
activity.runOnUiThread {
RSV.adapter = MainAdaptertasks(tasksfeed)
if(taskfragmentprogressbar != null){
taskfragmentprogressbar.visibility = View.INVISIBLE
}
//ChatAdapter(Context, tasksfeed)
}
}
override fun onFailure(call: Call?, e: IOException?) {
println("Failed to execute request")
}
})
}
// TODO: Rename method, update argument and hook method into UI event
fun onButtonPressed(uri: Uri) {
if (mListener != null) {
mListener!!.onFragmentInteraction(uri)
}
}
companion object {
fun newInstance(): Fragmenttask {
val fragment = Fragmenttask()
val args = Bundle()
fragment.arguments = args
return fragment
}
}
}// Required empty public constructor
......................................................................................................................................