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How to display JSON data from Horizontal recycle view kotlin using MVP method

I hope is all well with you.
I have constructed my code and build according the MVP style as well pulling JSON data but when I run the the code the horizontal recycle view and the JSON data is not being displayed. I tried going through every line of code and watching other tutorials but still no results.
Here is below my main activity:
class ProductCategoryActivity : BaseMvpActivity<ProductCategoryActivityView, ProductCategoryActivityPresnter> (),
ProductCategoryActivityView, CategoryAdapter.onItemClickListener{
private lateinit var binding: FragmentProductCategoryBinding
val data :MutableList<CateogryResponse> = ArrayList()
val adapter= CategoryAdapter(data, this)
#Inject
lateinit var presenter: ProductCategoryActivityPresnter
#Inject
lateinit var progressDialog: ProgressDialog
override fun onCreateComponent() {
userComponent.plus(CategoryActivityModule(this)).inject(this)
}
override fun providePresenter(): ProductCategoryActivityPresnter {
return presenter
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = FragmentProductCategoryBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
presenter.fetchcatogries()
showdata(ArrayList())
}
override fun showError(message: String) {
}
override fun showProgress() {
}
override fun hideProgress() {
}
override fun showdata(data: ArrayList<CateogryResponse>) {
val layoutManager = LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false)
recyclerViewPrimary.layoutManager = layoutManager
recyclerViewPrimary.setHasFixedSize(true)
recyclerViewPrimary.adapter = adapter
for(i in data)
data.add(CateogryResponse("product"))
}
override fun onItemClick(position: Int) {
Toast.makeText(this, "Item $position clicked", Toast.LENGTH_SHORT).show()
val clickedItem = data[position]
adapter.notifyItemChanged(position)
}
}
Here is my presenter:
#ActivityScope
class ProductCategoryActivityPresnter #Inject constructor(
private val stringProvider: StringProvider,
#AndroidScheduler private val observeOnScheduler: Scheduler,
#IOScheduler private val subscribeOnScheduler: Scheduler,
private val getCategoryUseCase: CategoryUseCase
) : BasePresenter<ProductCategoryActivityView>() {
lateinit var catogriesservice: CategoryRepositoryImpl
val catogriesLoadError = MutableLiveData<Boolean>()
val loading = MutableLiveData<Boolean>()
var catogries: ArrayList<CateogryResponse> = arrayListOf()
override fun onCreatePresenter(savedInstanceState: Bundle?) {
}
override fun onSaveInstanceState(outState: Bundle?) {
}
override fun onLoadData(arguments: Bundle?) {
fetchcatogries()
}
fun fetchcatogries() {
getCategoryUseCase.execute()
.observeOn(observeOnScheduler)
.subscribeOn(subscribeOnScheduler)
.subscribe(
SingleRequestSubscriber(
{
it
if (it != null && it.size > 0) {
catogries.removeAll(catogries)
catogries.addAll(it)
}
},
onFailure = { appException ->
view?.showError(
ErrorHandler.getErrorMessage(
appException,
stringProvider
)
)
},
onApiError = { apiException ->
view?.showError(
ErrorHandler.getErrorMessage(
apiException,
stringProvider
)
)
},
onAuthenticationError = { requestxception ->
view?.showError(
ErrorHandler.getErrorMessage(
requestxception,
stringProvider
)
)
},
onShowProgress = {
if (it) {
view?.showProgress()
} else {
view?.hideProgress()
}
},
onSubscribed = {
disposable.add(it)
})
)
}
}
Here is my view:
interface ProductCategoryActivityView {
fun showError(message: String)
fun showProgress()
fun hideProgress()
fun showdata ( data: ArrayList<CateogryResponse>)
}
Here is my adapter:
class CategoryAdapter(
private val data: List<CateogryResponse>,
private val listener: onItemClickListener
) : RecyclerView.Adapter<CategoryAdapter.ViewHolder>() {
private val items: MutableList<CardView>
init {
this.items = ArrayList()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val v = LayoutInflater.from(parent.context)
.inflate(R.layout.fragment_category_adapter, parent, false)
return ViewHolder(v)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.tvTitle.text = data[position].product
items.add(holder.card)
}
override fun getItemCount(): Int {
return data.size
}
inner class ViewHolder(itemView: View
) : RecyclerView.ViewHolder(itemView),
View.OnClickListener {
val tvTitle: TextView = itemView.featured_title
val card: CardView = itemView.CardView
init {
itemView.setOnClickListener(this)
}
override fun onClick(v: View?) {
val position: Int = adapterPosition
if (position != RecyclerView.NO_POSITION) {
listener.onItemClick(position)
}
}
}
interface onItemClickListener {
fun onItemClick(position: Int)
}
}
Image:
Fragment Category Adapter:
android:id="#+id/CardView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
app:cardCornerRadius="2dp"
app:cardElevation="8dp">
<!-- We Will Add here the card & ImageViews -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="15dp">
<ImageView
android:id="#+id/featured_image"
android:layout_width="match_parent"
android:layout_height="140dp"
android:scaleType="centerCrop" />
<TextView
android:id="#+id/featured_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:lineHeight="23dp"
android:text="Chairs"
android:textColor="#color/colorAccent"
android:textSize="20sp" />
<TextView
android:id="#+id/featured_desc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="asbkd asudhlasn saudnas jasdjasl hisajdl asjdlnas" />
</LinearLayout>
</androidx.cardview.widget.CardView>
Fragment Product Category:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#fafcfe"
tools:context="ui.category.ProductCategoryActivity">
<ImageView
android:id="#+id/imageView3"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
/>
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/constraintLayout"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="32dp"
android:layout_marginTop="48dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="#+id/imageView"
app:layout_constraintTop_toTopOf="parent">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerViewPrimary"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="48dp"
android:layout_marginTop="20dp"
android:text="#string/topselling"
android:textSize="18sp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/constraintLayout" />
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/constraintLayout2"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="32dp"
android:layout_marginLeft="32dp"
android:layout_marginTop="16dp"
app:layout_constraintBottom_toTopOf="#+id/imageView3"
app:layout_constraintEnd_toEndOf="#+id/constraintLayout"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/textView">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerViewSecondary"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
<ImageView
android:id="#+id/imageView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="32dp"
app:layout_constraintBottom_toBottomOf="#+id/imageView3"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.498"
app:layout_constraintStart_toStartOf="parent"
/>
<TextView
android:id="#+id/textViewCategories"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="48dp"
android:layout_marginTop="20dp"
android:layout_marginBottom="15dp"
android:text="#string/catogries"
android:textSize="18sp"
app:layout_constraintBottom_toTopOf="#+id/constraintLayout"
app:layout_constraintStart_toStartOf="parent"
tools:layout_editor_absoluteX="39dp" />
</androidx.constraintlayout.widget.ConstraintLayout>
Not sure what went wrong.
If someone can point it out or show me what needs to be done to be able to display the data in horzintal recycle view, I would be really thanlful

You should update your recycler view adapter once your fetch call is executed, not before it ends.
Modify your fetchcatogries declaration so it accepts a callback method, which will be executed after the data are loaded.
This method will accept a list object as a parameter, which you will manage in your ProductCategoryActivity to populate the RecyclerView.
fun fetchcatogries(callback: (MutableList<CateogryResponse>) -> Unit) {
getCategoryUseCase.execute()
.observeOn(observeOnScheduler)
.subscribeOn(subscribeOnScheduler)
.subscribe(
SingleRequestSubscriber(
{ categories ->
callback(categories)
},
...
)
}
You can now edit your onCreate and showdata methods in ProductCategoryActivity like this:
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = FragmentProductCategoryBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
presenter.fetchcatogries { categories ->
showdata(categories as ArrayList<CateogryResponse>)
}
}
override fun showdata(data: ArrayList<CateogryResponse>) {
val layoutManager = LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false)
recyclerViewPrimary.layoutManager = layoutManager
recyclerViewPrimary.setHasFixedSize(true)
recyclerViewPrimary.adapter = CategoryAdapter(data.toList(), this)
}

Android - Binding adapter failed to load a text

I write simple app displaying cocktails list. The problem is there's no title text but the pics is loading with picasso working just fine. I suppose the weak point in my Binding Adapter. Cause I can't just pass data value, i need to pass data?.list and I am really confused why I can't. Please help!
The app result
CocktailListFragment.kt
class CocktailListFragment : Fragment() {
private val viewModel: CocktailListViewModel by lazy {
ViewModelProvider(this).get(CocktailListViewModel::class.java)
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
val binding = CocktailListFragmentBinding.inflate(inflater)
binding.lifecycleOwner = this
setHasOptionsMenu(true)
binding.cocktail = viewModel
binding.cocktailList.adapter = CocktailListAdapter()
return binding.root
}
override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
inflater.inflate(R.menu.filter_menu, menu)
super.onCreateOptionsMenu(menu, inflater)
}
}
CocktailListViewModel.kt
class CocktailListViewModel : ViewModel() {
private val _cocktails = MutableLiveData<CocktailsList>()
val cocktails: LiveData<CocktailsList>
get() = _cocktails
private var viewModelJob = Job()
private val coroutineScope = CoroutineScope(viewModelJob + Dispatchers.Main)
init {
getCocktails()
}
private fun getCocktails() {
coroutineScope.launch {
val getCocktailsDeferred = CocktailsApi.RETROFIT_SERVICE.getCocktailsAsync()
try {
val result = getCocktailsDeferred.await()
_cocktails.value = result
} catch (e: Exception) {
Log.d("error", "error")
}
}
}
override fun onCleared() {
super.onCleared()
viewModelJob.cancel()
}
}
CocktailListAdapter.kt
class CocktailListAdapter :
ListAdapter<Cocktail, CocktailListAdapter.CocktailListViewHolder>(DiffCallback) {
class CocktailListViewHolder(private var binding: CocktailItemBinding) :
RecyclerView.ViewHolder(binding.root) {
fun bind(cocktail: Cocktail) {
binding.cocktail = cocktail
binding.executePendingBindings()
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CocktailListViewHolder {
return CocktailListViewHolder(CocktailItemBinding.inflate(LayoutInflater.from(parent.context)))
}
override fun onBindViewHolder(holder: CocktailListViewHolder, position: Int) {
val cocktail = getItem(position)
holder.bind(cocktail)
}
companion object DiffCallback : DiffUtil.ItemCallback<Cocktail>() {
override fun areItemsTheSame(oldItem: Cocktail, newItem: Cocktail): Boolean {
return oldItem === newItem
}
override fun areContentsTheSame(oldItem: Cocktail, newItem: Cocktail): Boolean {
return oldItem.id == newItem.id
}
}
}
CocktailDataClass
data class CocktailsList(
#SerializedName("drinks")
val list: List<Cocktail>
)
data class Cocktail (
#SerializedName("idDrink")
val id: String,
#SerializedName("strDrinkThumb")
val drinkImg: String,
#SerializedName("strDrink")
val drinkTitle: String
)
BindingAdapters - I think the problem is in binding adapter for list data:
#BindingAdapter("listData")
fun bindRecyclerView(recyclerView: RecyclerView, data: CocktailsList?) {
val adapter = recyclerView.adapter as CocktailListAdapter
adapter.submitList(data?.list)
}
#BindingAdapter("strDrinkThumb")
fun bindImage(imgView: ImageView, imgUrl: String?) {
imgUrl?.let {
val imgUri = imgUrl.toUri().buildUpon().scheme("https").build()
Picasso.get()
.load(imgUri)
.placeholder(R.drawable.loading_animation)
.error(R.drawable.ic_broken_image)
.into(imgView)
}
}
cocktail_list_fragemnt.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="cocktail"
type="com.example.coctaildb.cocktaillist.CocktailListViewModel" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/appBarLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:elevation="30dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<com.google.android.material.appbar.MaterialToolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
style="#style/Widget.AppCompat.Toolbar"
android:background="#android:color/white"
app:menu="#menu/filter_menu"
app:title="#string/drinks"
app:titleTextColor="#android:color/black" />
</com.google.android.material.appbar.AppBarLayout>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/cocktail_list"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/appBarLayout2"
app:listData="#{cocktail.cocktails}"
tools:listitem="#layout/cocktail_item" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
cocktail_item.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="cocktail"
type="com.example.coctaildb.network.Cocktail" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ImageView
android:id="#+id/cocktail_img"
android:layout_width="100dp"
android:layout_height="100dp"
android:maxHeight="100dp"
android:scaleType="centerCrop"
android:layout_marginStart="20dp"
android:layout_marginTop="20dp"
android:layout_marginBottom="20dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:strDrinkThumb="#{cocktail.drinkImg}"
tools:srcCompat="#tools:sample/avatars" />
<TextView
android:id="#+id/cocktail_title"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="21dp"
android:layout_marginTop="40dp"
android:layout_marginEnd="20dp"
android:fontFamily="#font/roboto"
android:text="#{cocktail.drinkTitle}"
android:textColor="#7E7E7E"
android:textSize="16sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintStart_toEndOf="#+id/cocktail_img"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>

Data binding in recylerview adapter android?

I want to bind data to my recylerview adapter. This is my current code following the MVVM pattern
Fragment
class NotificationFragment : Fragment() {
var customeProgressDialog: CustomeProgressDialog? = null
private val appPreferences: AppPreference by inject()
private val notificationViewModel: NotificationViewModel by viewModel()
private lateinit var binding: FragmentNotificationBinding
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
binding = FragmentNotificationBinding.inflate(inflater, container, false)
return binding.getRoot()
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
binding.notification.layoutManager=LinearLayoutManager(activity, LinearLayoutManager.VERTICAL, false)
customeProgressDialog = CustomeProgressDialog(activity)
notificationViewModel.notifications(
appPreferences.getUsername(),
appPreferences.getPassword(),
appPreferences.getUserId()
)
initObservables()
}
private fun initObservables() {
notificationViewModel.progressDialog?.observe(this, Observer {
if (it!!) customeProgressDialog?.show() else customeProgressDialog?.dismiss()
})
notificationViewModel.apiResponse?.observe(
viewLifecycleOwner,
androidx.lifecycle.Observer { response ->
if (response.dataList != null) {
val notificationAdapter = NotificationAdapter(response.dataList as List<Data>)
notificationAdapter.notifyDataSetChanged()
binding.notification.adapter = notificationAdapter
}
})
}
}
View model
class NotificationViewModel(networkCall: NetworkCall) : ViewModel(),
Callback<ApiResponse> {
var progressDialog: SingleLiveEvent<Boolean>? = null
var apiResponse: MutableLiveData<ApiResponse>? = null
var networkCall: NetworkCall;
init {
progressDialog = SingleLiveEvent<Boolean>()
apiResponse = MutableLiveData<ApiResponse>()
this.networkCall = networkCall
}
fun notifications(username: String?, password: String?, userId: String?) {
progressDialog?.value = true
val apiPost = ApiPost()
apiPost.userName = username
apiPost.password = password
apiPost.UserId = userId
apiPost.FileType = NetworkConstant.FILE_TYPE_NOT
networkCall.getPDF(apiPost).enqueue(this)
}
override fun onFailure(call: Call<ApiResponse>, t: Throwable) {
progressDialog?.value = false
}
override fun onResponse(call: Call<ApiResponse>, response: Response<ApiResponse>) {
progressDialog?.value = false
apiResponse?.value = response.body()
}
}
The adapter
class NotificationAdapter(private val list: List<Data>) :
RecyclerView.Adapter<NotificationAdapter.ViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val inflater = LayoutInflater.from(parent.context)
val binding = ElementListBinding.inflate(inflater)
// val view = inflater.inflate(R.layout.element_list, parent, false)
return ViewHolder(binding)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val movie: Data = list[position]
holder.bind(movie)
holder.itemView.setOnClickListener {
if (!TextUtils.isEmpty(movie.filePath)) {
try {
val browserIntent = Intent(Intent.ACTION_VIEW, Uri.parse(movie.filePath))
holder.itemView.context.startActivity(browserIntent)
} catch (e: Exception) {
e.printStackTrace()
}
}
}
}
override fun getItemCount(): Int = list.size
inner class ViewHolder(binding: ElementListBinding) : RecyclerView.ViewHolder(binding.root) {
fun bind(movie: Data) {
binding.item = movie
}
}
}
unable to find binding object
the recylerview element list xml
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<data>
<variable
name="data"
type="com.mountmeru.model.Data" />
</data>
<androidx.cardview.widget.CardView
android:id="#+id/main_cardview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="5dp">
<androidx.appcompat.widget.LinearLayoutCompat
android:id="#+id/main_cardrl"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<RelativeLayout
android:id="#+id/rl_newsdate"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="0.3">
<androidx.appcompat.widget.AppCompatTextView
android:id="#+id/tv_notifi"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginTop="10dp"
android:layout_marginRight="10dp"
android:maxLines="2"
android:text="#{data.displayName}"
android:textColor="#android:color/black"
android:textSize="16sp" />
<androidx.appcompat.widget.AppCompatTextView
android:id="#+id/tv_brief"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/tv_notifi"
android:layout_marginLeft="10dp"
android:layout_marginTop="5dp"
android:layout_marginRight="10dp"
android:textColor="#android:color/black"
android:textSize="16sp"
android:visibility="gone" />
<androidx.appcompat.widget.AppCompatTextView
android:id="#+id/tv_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/tv_brief"
android:layout_marginLeft="10dp"
android:layout_marginTop="2dp"
android:layout_marginRight="10dp"
android:maxLines="1"
android:text="hey i am date"
android:textColor="#color/inactive_text"
android:textSize="14sp" />
</RelativeLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_toRightOf="#+id/rl_newsdate"
android:layout_weight="0.7"
android:padding="5dp">
<androidx.appcompat.widget.AppCompatImageView
android:id="#+id/iv_notifi"
android:layout_width="match_parent"
android:layout_height="75dp"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:src="#drawable/mer" />
</RelativeLayout>
</androidx.appcompat.widget.LinearLayoutCompat>
</androidx.cardview.widget.CardView>
</layout>
Can someone confirm me is my implementation of MVVM correct or it needs some refactoring?
How do I make of data binding in my recyclerview list element xml?

You have already used <layout> as parent tag in element_list.xml. Now you can inflate it in the adapter class using DataBinding. See the example below:
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val binding = ElementListBinding.inflate(LayoutInflater.from(parent.context), parent, false)
return ViewHolder(Binding)
}
You have to modify your ViewHolder class as well as shown below:
inner class ViewHolder(val binding: ElementListBinding) : RecyclerView.ViewHolder(binding.root) {
fun bind(movie: Data) {
with(itemView) {
binding.tvNotifi.text = movie.displayName
binding.tvDate.text = movie.UpdatedDate
if (movie.description != null) {
binding.tvBrief.text = movie.description
binding.tvBrief.visibility = View.VISIBLE
}
}
}
}

how to binding correctly recyclerview items in kotlin?

I am developing a news app and I am following MVVM with data binding in recycler view I am trying to bind items but I am just stuck below my recyclerview items xml file
<?xml version="1.0" encoding="utf-8"?>
<layout>
<data>
<variable
name="article"
type="yodgorbek.komilov.musobaqayangiliklari.model.Article">
</variable>
</data>
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginBottom="16dp">
<ImageView
android:text="#{article.urlToImage}"
android:id="#+id/imageView"
android:layout_width="100dp"
android:layout_height="85dp"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:contentDescription="bbc"
tools:background="#color/colorPrimary" />
<TextView
android:id="#+id/articleTitle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginEnd="16dp"
android:layout_toEndOf="#id/imageView"
android:layout_toRightOf="#id/imageView"
android:ellipsize="end"
android:lines="3"
android:maxLines="3"
android:text="#{article.title}" />
<ImageView
android:id="#+id/imageCategory"
android:layout_width="32dp"
android:layout_height="32dp"
android:layout_below="#id/articleTitle"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:layout_toEndOf="#id/imageView"
android:layout_toRightOf="#id/imageView"
android:src="#drawable/ic_espn"
tools:background="#color/colorPrimary" />
<TextView
android:id="#+id/articleSourceName"
android:layout_width="wrap_content"
android:layout_height="32dp"
android:layout_below="#id/articleTitle"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:layout_toEndOf="#id/imageCategory"
android:layout_toRightOf="#id/imageCategory"
android:gravity="center|start"
android:text="#{article.source.name}" />
<TextView
android:id="#+id/articleTime"
android:layout_width="wrap_content"
android:layout_height="32dp"
android:layout_below="#id/articleTitle"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_marginStart="16dp"
android:layout_marginEnd="16dp"
android:layout_toEndOf="#id/articleSourceName"
android:layout_toRightOf="#id/articleSourceName"
android:gravity="center|start"
android:text="#{article.publishedAt}"
android:textColor="#android:color/darker_gray"
tools:ignore="NotSibling" />
</RelativeLayout>
</androidx.cardview.widget.CardView>
</layout>
below TopHeadlinesAdapter.kt where I am trying to implement data binding logic
#Suppress("NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS")
class TopHeadlinesAdapter(val context: Context, private val article: List<Article>) :
RecyclerView.Adapter<TopHeadlinesAdapter.MyViewHolder>() {
private var articleList: List<Article> by Delegates.observable(emptyList()) { _, _, _ ->
notifyDataSetChanged()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val inflater =
LayoutInflater.from(parent.context)//.inflate(R.layout.news_list, parent, false)
// val binding = Article.inflate(inflater)
return MyViewHolder(article, parent)
}
override fun getItemCount(): Int {
return articleList.size
}
#SuppressLint("NewApi")
override fun onBindViewHolder(holder: MyViewHolder, position: Int) =
holder.bind(articleList[position])
//holder.articleTitle.text = articleList.get(position).title
//holder.articleSourceName.text = articleList.get(position).source.name
//Picasso.get().load(articleList.get(position).urlToImage).into(holder.image)
// val input = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssX")
// val output = SimpleDateFormat("dd/MM/yyyy")
// var d = Date()
// try {
// d = input.parse(articleList[5].publishedAt)
// } catch (e: ParseException) {
// try {
// val fallback = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'")
// fallback.timeZone = TimeZone.getTimeZone("UTC")
// d = fallback.parse(articleList[5].publishedAt)
// } catch (e2: ParseException) {
// // TODO handle error
// val formatted = output.format(d)
// val timelinePoint = LocalDateTime.parse(formatted)
// val now = LocalDateTime.now()
//
// var elapsedTime = Duration.between(timelinePoint, now)
//
// println(timelinePoint)
// println(now)
// elapsedTime.toMinutes()
//
// holder.articleTime.text = "${elapsedTime.toMinutes()}"
//
//
fun updateData(newList: List<Article>) {
articleList = newList
Log.e("articleListSize", articleList?.size.toString())
}
inner class MyViewHolder(private val binding: Article) : RecyclerView.ViewHolder(binding.root) {
fun bind(article: Article) {
binding.article = article
// val image: ImageView = itemView!!.findViewById(R.id.imageView)
// val articleTitle: TextView = itemView!!.findViewById(R.id.articleTitle)
// val articleSourceName: TextView = itemView!!.findViewById(R.id.articleSourceName)
// val imageCategory: ImageView = itemView!!.findViewById(R.id.imageCategory)
// val articleTime: TextView = itemView!!.findViewById(R.id.articleTime)
}
}
}
below my Article.kt data class
data class Article(
val author: String,
val content: String,
val description: String,
val publishedAt: String,
val source: Source,
val title: String,
val url: String,
val urlToImage: String
)
below fragment_top_headlines.xml where I am hosting recyclerview
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ProgressBar
android:id="#+id/pb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
below TopHeadlinesFragment.kt
class TopHeadlinesFragment : Fragment() {
private val viewModel by viewModel<MainViewModel>()
private lateinit var topHeadlinesAdapter: TopHeadlinesAdapter
// private val newsRepository: NewsRepository by inject()
private lateinit var article:List<Article>
//3
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val view = inflater.inflate(
R.layout.fragment_top_headlines
, container, false
)
val recyclerView = view.findViewById(R.id.recyclerView) as RecyclerView
val pb = view.findViewById(R.id.pb) as ProgressBar
topHeadlinesAdapter = TopHeadlinesAdapter(recyclerView.context, article)
recyclerView.layoutManager = LinearLayoutManager(context)
recyclerView.adapter = topHeadlinesAdapter
initViewModel()
return view
}
private fun initViewModel() {
viewModel?.sportList?.observe(this, Observer { newList ->
topHeadlinesAdapter.updateData(newList)
})
viewModel?.showLoading?.observe(this, Observer { showLoading ->
pb.visibility = if (showLoading) View.VISIBLE else View.GONE
})
viewModel?.showError?.observe(this, Observer { showError ->
(showError)
})
viewModel?.loadNews()
}
}
I want to know what I have to do in order to bind correctly recyclerview items and show correctly in my app?

try this in
class yourAdapterName(val context: Context, var listData:
MutableList<Article>) :
RecyclerView.Adapter<LanguageAdapter.ViewHolder>() {
lateinit var bindind: YourBinding
fun onRefresh(listData: MutableList<Article>) {
this.listData = listData
notifyDataSetChanged()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int):
ViewHolder {
bindind = YourBinding.inflate(LayoutInflater.from(parent.context), parent, false)
return ViewHolder(bindind)
}
override fun getItemCount(): Int {
return listData.size
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.setData(listData[position])
}
inner class ViewHolder(private val binding: LangugaeItemBinding) : RecyclerView.ViewHolder(binding.getRoot()) {
fun setData(model: Article) {
with(binding) {
artical = model
executePendingBindings()
}
}
}
}
and call these into onViewCreated in fragment
val recyclerView = view.findViewById(R.id.recyclerView) as
RecyclerView
val pb = view.findViewById(R.id.pb) as ProgressBar
topHeadlinesAdapter = TopHeadlinesAdapter(recyclerView.context,
article)
recyclerView.layoutManager = LinearLayoutManager(context)
recyclerView.adapter = topHeadlinesAdapter
initViewModel()

Kotlin Android Recycler view inside Fragment with Bottom Navigation not working

I am trying to develop social networking app which uses Android Jetpack Libraries but while using Navigation Component to use bottom navigation to navigate through fragments inside an activity , This Adapter throws an error at LayoutInflator() which causes app to crash
Can anyone help me through this:
My Adapter Class:
class FeedAdapter : PagedListAdapter<feed,FeedAdapter.ViewHolder>(FeedDiffCallBack()){
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val userPost = LayoutInflater.from(parent.context)
.inflate(R.layout.feedrow,parent,false)
return ViewHolder(userPost)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val feedItem = getItem(position)
if(feedItem != null){
holder.bind(feedItem)
}
}
class ViewHolder(itemView:View):RecyclerView.ViewHolder(itemView) {
//Retrieve data
private val username:TextView = itemView.post_name
private val userPic:ImageView = itemView.feedImage1
private val location:TextView = itemView.postLocation
private val time:TextView = itemView.postTime
private val post:ImageView = itemView.postImage
fun bind(feed: feed) = with(itemView){
//TODO:Bind Data with View
showFeedData(feed)
}
private fun showFeedData(feed: feed) {
username.text = feed.username
userPic.setImageURI(null)
userPic.visibility = View.GONE
location.text = feed.location
time.text = feed.timeStamp.toString()
post.setImageURI(Uri.parse(feed.mUrl))
}
}
}
class FeedDiffCallBack : DiffUtil.ItemCallback<feed>() {
override fun areItemsTheSame(oldItem:feed, newItem: feed): Boolean {
return oldItem?.id == newItem?.id
}
override fun areContentsTheSame(oldItem: feed, newItem: feed): Boolean {
return oldItem == newItem
}
}
Fragment Class:
class FeedFragment : Fragment() {
companion object {
fun newInstance() = FeedFragment()
}
private lateinit var viewModel: FeedViewModel
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val view = inflater.inflate(R.layout.feed_fragment, container, false)
val context = getContext() ?: return view
val factory = InjectorUtils.provideViewModelFactory(context)
viewModel =
ViewModelProviders.of(this,factory).get(FeedViewModel::class.java)
val adapter = FeedAdapter()
view.findViewById<RecyclerView>(R.id.feedView).adapter = adapter
view.findViewById<RecyclerView>(R.id.feedView).layoutManager =
LinearLayoutManager(MyApplication.getContext())
subscribeUI(adapter)
return view
}
private fun subscribeUI(adapter: FeedAdapter) {
viewModel.showFeed().observe(this, object:Observer<PagedList<feed>>{
override fun onChanged(t: PagedList<feed>?) {
adapter.submitList(t)
adapter.notifyDataSetChanged()
}
})
}
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
}
}
feed_row.xml
Individual item for recycler view -->
<RelativeLayout
android:id="#+id/postContainer"
android:layout_margin="10dp"
android:elevation="2dp"
android:background="#drawable/bg_parent_rounded_corner"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!--TODO:Change to Circle Image View-->
<ImageView
android:id="#+id/profileImage"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_marginTop="5dp"
android:layout_marginLeft="5dp"
android:adjustViewBounds="true"
android:scaleType="fitCenter"
/>
<LinearLayout
android:id="#+id/postDetail_1"
android:orientation="vertical"
android:layout_marginTop="5dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="5dp"
android:layout_marginRight="20dp"
android:layout_alignParentRight="true">
<TextView
android:id="#+id/post_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
style="#style/LabelStyle"
android:textSize="15sp"
android:fontFamily="#font/sf_pro_display_semibold" />
<LinearLayout
android:id="#+id/postDetail_2"
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:id="#+id/postLocation"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/postTime"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="120dp" />
</LinearLayout>
</LinearLayout>
<ImageView
android:id="#+id/postImage"
android:layout_height="200dp"
android:layout_width="match_parent"
android:layout_below="#+id/postDetail_1"
android:adjustViewBounds="true"
android:scaleType="fitCenter"
android:layout_marginTop="6dp"
/>
</RelativeLayout>

Your issue might be in this method,
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val feedItem = getItem(position)
if(feedItem != null){
holder.bind(feedItem)
}
}
Your ViewHolder is using poisition from method parameter which might be inconsistent
See from here,
So, you should change line to this:
val feedItem = getItem(holder.adapterPosition)
instead of
val feedItem = getItem(position)
I hope it resolves the issue.

This might help some one looking for the same Exception to be cleared :
What I did is that my feed_row.xml above is included inside < layout > tags and I changed it in this way , So the exception got cleared:
Before Exception:
<layout xmlns:android="http://schemas.android.com/apk/res/android">
After changing to this Exception cleared:
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
I don't know how it works but it did work!!! So Anyone who knows what happens there can explain please!