Develop Reference

Recycler view data not loading on screen

I'm trying to show the recycler view's data on my app. The thing is, even though the NetworkStatus is successful (I can tell because I don't get the toast's message and the loader disappears and I can also see the data in the logcat), the info is not displayed. I am not sure if the error is in the way I'm calling the recycler view on my MainActivity or in the RecyclerAdapter but any idea as to where the problem is would be very helpful.
This is the RecyclerAdapter:
import android.view.LayoutInflater
import android.view.ViewGroup
import android.widget.TextView
import androidx.recyclerview.widget.RecyclerView
import com.app.mortyapp.databinding.ItemDetailBinding
class RecyclerAdapter(private var characterList: List<Character>): RecyclerView.Adapter<RecyclerAdapter.ViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerAdapter.ViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
val binding = ItemDetailBinding.inflate(
layoutInflater,
parent,
false
)
return ViewHolder(binding)
}
override fun getItemCount(): Int = characterList.size
override fun onBindViewHolder(holder: RecyclerAdapter.ViewHolder, position: Int) {
holder.bind(characterList[position])
}
fun setCharacterList(characterList: List<Character>){
this.characterList = characterList
notifyDataSetChanged()
}
inner class ViewHolder(
private val binding: ItemDetailBinding
) : RecyclerView.ViewHolder(binding.root){
fun bind(character: Character) {
with(binding){
val itemName: TextView = binding.tvName
val itemGender: TextView = binding.tvGender
itemName.text = character.name
itemGender.text = character.gender
}
}
}
}
This is the MainActivity:
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.widget.ProgressBar
import android.widget.Toast
import androidx.activity.viewModels
import androidx.lifecycle.Observer
import androidx.recyclerview.widget.LinearLayoutManager
import com.app.mortyapp.databinding.ActivityMainBinding
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
private val characters = mutableListOf<Character>()
private lateinit var progressBar: ProgressBar
private lateinit var recyclerAdapter: RecyclerAdapter
private val viewModel: MainViewModel by viewModels(
factoryProducer = {MainViewModelFactory()}
)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)
progressBar = binding.ProgressBar
progressBar.visibility = View.INVISIBLE
setObservers()
initRecyclerView()
}
private fun initRecyclerView() {
with(binding.rvCharacters){
layoutManager = LinearLayoutManager(context)
recyclerAdapter = RecyclerAdapter(characters).apply {
setCharacterList(characters)
}
}
}
private fun setObservers(){
viewModel.characterList.observe(this, Observer {
when(it.status){
NetworkStatus.LOADING ->{
//show loading state
progressBar.visibility = View.VISIBLE
}
NetworkStatus.SUCCESS -> {
//hide loading state
progressBar.visibility = View.INVISIBLE
//render character list
recyclerAdapter.setCharacterList(characters)
}
NetworkStatus.ERROR -> {
//show error message
Toast.makeText(this,"Error loading content", Toast.LENGTH_SHORT).show()
//hide loading state
progressBar.visibility = View.INVISIBLE
}
}
})
}
}
API response:
import com.google.gson.annotations.SerializedName
data class Character (
#SerializedName("id") val id: Int,
#SerializedName("name") val name: String,
#SerializedName("gender") val gender: String
)
data class CharacterListResponse(
#SerializedName("results") val results: List<Character>
)
Remote data source:
package com.app.mortyapp
import com.app.mortyapp.Model.CharacterService
import com.app.mortyapp.Model.RetrofitServices
import retrofit2.Call
import retrofit2.Callback
import retrofit2.Response
class CharacterRemoteDataSource {
fun getCharacterList(networkResponse: NetworkResponse<List<Character>>) {
val service = RetrofitServices.instance
.create(CharacterService::class.java)
.getCharacterList()
service.enqueue(object : Callback<CharacterListResponse> {
override fun onResponse(
call: Call<CharacterListResponse>,
response: Response<CharacterListResponse>
) {
val resource = response.body()?.run {
if (results.isNotEmpty())
Resource(NetworkStatus.SUCCESS, results)
else
Resource(NetworkStatus.ERROR)
} ?: run {
Resource(NetworkStatus.ERROR)
}
networkResponse.onResponse(resource)
}
override fun onFailure(call: Call<CharacterListResponse>, t: Throwable) {
networkResponse.onResponse(Resource(NetworkStatus.ERROR, message = t.message))
}
})
}
}
interface NetworkResponse<T> {
fun onResponse(value: Resource<T>)
}

Set adapter for Recyclerview in
setupRecylerview ()
adapter = recyclerAdapter
NetworkStatus.SUCCESS -> {
//hide loading state
progressBar.visibility = View.INVISIBLE
//render character list
recyclerAdapter.setCharacterList(characters)
recyclerAdapter.notifydatasetchanged()//add this line
}

I think most problems found with recyclerView isn't linked to it, but with some adjourning codes. For example, a very similar problem was solved by finding out that the adapter POJO class was retrieving 0 rather than the actual size of the array list.
See the solved problem here:
Android Recycler View not loading Data (Peculiar problem, Not a Duplicate)

intent.putExtra: None of the following functions can be called with the arguments supplied

I'm trying to pass data from one activity to another through an intent with putExtra. The thing is, I get the error that says: None of the following functions can be called with the arguments supplied.
I'm not sure why it's not working, since the variable that I'm referencing is in the viewholder. Any clue as to what's going on and how to fix it would help a lot.
This is my recycler adapter:
package com.example.newsapp
import android.content.Intent
import android.icu.text.CaseMap
import android.net.Uri
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.AdapterView
import android.widget.ImageView
import android.widget.TextView
import androidx.core.content.ContextCompat.startActivity
import androidx.recyclerview.widget.RecyclerView
import com.example.newsapp.databinding.NewsItemBinding
import com.squareup.picasso.Picasso
class RecyclerAdapter (
private var Titles: List<String>,
private var Images: List<String>,
private var Authors: List<String>,
private var Descriptions: List<String>
) : RecyclerView.Adapter<RecyclerAdapter.ViewHolder>(){
inner class ViewHolder(
view: View
): RecyclerView.ViewHolder(view){
private val binding = NewsItemBinding.bind(view)
val itemTitle: TextView = binding.tvTitle
val itemImage: ImageView = binding.ivNewsImage
fun bind(urlToImage:String){
Picasso.get().load(urlToImage).into(binding.ivNewsImage)
}
init {
itemImage.setOnClickListener{
val intent = Intent(view.context, PostActivity::class.java)
intent.putExtra("title",itemTitle)
view.context.startActivity(intent)
}
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val v = LayoutInflater.from(parent.context).inflate(R.layout.news_item, parent, false)
return ViewHolder(v)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.itemTitle.text = Titles[position]
val itemImage = Images[position]
holder.bind(itemImage)
}
override fun getItemCount(): Int {
return Titles.size
}
}
The part with the issue is this one:
init {
itemImage.setOnClickListener{
val intent = Intent(view.context, PostActivity::class.java)
intent.putExtra("title",itemTitle) view.context.startActivity(intent)
}
}
This is my main activity:
package com.example.newsapp
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import androidx.recyclerview.widget.LinearLayoutManager
import com.example.newsapp.databinding.ActivityMainBinding
import kotlinx.coroutines.*
import retrofit2.Retrofit
import retrofit2.converter.gson.GsonConverterFactory
import java.lang.Exception
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
private lateinit var adapter: RecyclerAdapter
private val newsTitles = mutableListOf<String>()
private val newsImages = mutableListOf<String>()
private val newsAuthors = mutableListOf<String>()
private val newsDescriptions = mutableListOf<String>()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)
makeAPIRequest()
}
private fun initRecyclerView() {
adapter = RecyclerAdapter( newsTitles, newsImages)
binding.rvNews.layoutManager = LinearLayoutManager(this)
binding.rvNews.adapter = adapter
}
private fun addToList(title:String, image:String, author:String, description:String){
newsTitles.add(title)
newsImages.add(image)
newsAuthors.add(author)
newsDescriptions.add(description)
}
private fun makeAPIRequest() {
val api = Retrofit.Builder()
.baseUrl("https://newsapi.org/")
.addConverterFactory(GsonConverterFactory.create())
.build()
.create(APIService::class.java)
GlobalScope.launch(Dispatchers.IO){
val response = api.getNews()
val posts = response.body()
try{
if (posts != null) {
for(art in posts.Articles){
Log.i("Main Activity", "Result = $art")
addToList(art.Title,art.urlToImage, art.Author, art.Description)
}
}
withContext(Dispatchers.Main){
initRecyclerView()
}
} catch (e:Exception){
Log.e("Main Activity", e.toString())
}
}
}
}

intent.putExtra("title",itemTitle)
Here, itemTitle is a TextView. You cannot pass a TextView between activities. You could switch to:
intent.putExtra("title",itemTitle.text)
...to put the text from the TextView into the extra.
Also, you might want to consider whether these should be separate activities or just two fragments (or composables) in a single activity.

Caused by: java.lang.InstantiationException: class WordViewModel has no zero argument constructor [duplicate]

This question already has answers here:
Possible to access AndroidViewModel of Activity via Fragment?
(2 answers)
Closed 2 years ago.
Cannot instantiate WordViewModel
Caused by: java.lang.InstantiationException: class com.example.roomwordsample.WordViewModel has no zero argument constructor
I am trying to display room data with recycler view but I cannot instantiate class via ViewModelProvider get method
WordViewModel.kt
package com.example.roomwordsample
import android.app.Application
import androidx.lifecycle.AndroidViewModel
import androidx.lifecycle.LiveData
import androidx.lifecycle.viewModelScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
class WordViewModel(application: Application) : AndroidViewModel(application) {
private val repository: WordRepository
// Using LiveData and caching what getAlphabetizedWords returns has several benefits:
// - We can put an observer on the data (instead of polling for changes) and only update the
// the UI when the data actually changes.
// - Repository is completely separated from the UI through the ViewModel.
val allWords: LiveData<List<Word>>
init {
val wordsDao = WordRoomDatabase.getDatabase(application, viewModelScope).wordDao()
repository = WordRepository(wordsDao)
allWords = repository.allWords
}
/**
* Launching a new coroutine to insert the data in a non-blocking way
*/
fun insert(word: Word) = viewModelScope.launch(Dispatchers.IO) {
repository.insert(word)
}
}
MainActivity.kt
package com.example.roomwordsample
import android.app.Activity
import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProvider
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.google.android.material.floatingactionbutton.FloatingActionButton
class MainActivity : AppCompatActivity() {
private val newWordActivityRequestCode = 1
private lateinit var wordViewModel: WordViewModel
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val recyclerView = findViewById<RecyclerView>(R.id.recyclerview)
val adapter = WordListAdapter(this)
recyclerView.adapter = adapter
recyclerView.layoutManager = LinearLayoutManager(this)
wordViewModel = ViewModelProvider(this).get(WordViewModel::class.java)
wordViewModel.allWords.observe(this, Observer { words ->
// Update the cached copy of the words in the adapter.
words?.let { adapter.setWords(it) }
})
val fab = findViewById<FloatingActionButton>(R.id.fab)
fab.setOnClickListener {
val intent = Intent(this#MainActivity, NewWordActivity::class.java)
startActivityForResult(intent, newWordActivityRequestCode)
}
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == newWordActivityRequestCode && resultCode == Activity.RESULT_OK) {
data?.getStringExtra(NewWordActivity.EXTRA_REPLY)?.let {
val word = Word(it)
wordViewModel.insert(word)
}
} else {
Toast.makeText(
applicationContext,
R.string.empty_not_saved,
Toast.LENGTH_LONG).show()
}
}
}

I solved this problem by
wordViewModel = ViewModelProvider(this).get(WordViewModel::class.java)
changing the above code with this:
wordViewModel = ViewModelProvider.AndroidViewModelFactory.getInstance(application).create(WordViewModel::class.java)

try to add view model factory to your view model class.
package com.example.roomwordsample
import android.app.Application
import androidx.lifecycle.AndroidViewModel
import androidx.lifecycle.LiveData
import androidx.lifecycle.viewModelScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
class WordViewModel(application: Application) : AndroidViewModel(application) {
private val repository: WordRepository
// Using LiveData and caching what getAlphabetizedWords returns has several benefits:
// - We can put an observer on the data (instead of polling for changes) and only update the
// the UI when the data actually changes.
// - Repository is completely separated from the UI through the ViewModel.
val allWords: LiveData<List<Word>>
init {
val wordsDao = WordRoomDatabase.getDatabase(application, viewModelScope).wordDao()
repository = WordRepository(wordsDao)
allWords = repository.allWords
}
/**
* Launching a new coroutine to insert the data in a non-blocking way
*/
fun insert(word: Word) = viewModelScope.launch(Dispatchers.IO) {
repository.insert(word)
}
class Factory(
private val app: Application
) : ViewModelProvider.Factory {
#Suppress("UNCHECKED_CAST")
override fun <T : ViewModel?> create(modelClass: Class<T>): T {
if (modelClass.isAssignableFrom(WordViewModel::class.java)) {
return WordViewModel(app) as T
}
throw IllegalArgumentException("Unknown ViewModel class")
}
}
}
Then in your MainActivity intialize your view model like this:
package com.example.roomwordsample
import android.app.Activity
import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProvider
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.google.android.material.floatingactionbutton.FloatingActionButton
class MainActivity : AppCompatActivity() {
private val newWordActivityRequestCode = 1
private val wordViewModel by viewModels<WordViewModel> {
WordViewModel.Factory(application)
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val recyclerView = findViewById<RecyclerView>(R.id.recyclerview)
val adapter = WordListAdapter(this)
recyclerView.adapter = adapter
recyclerView.layoutManager = LinearLayoutManager(this)
//wordViewModel = ViewModelProvider(this).get(WordViewModel::class.java)
wordViewModel.allWords.observe(this, Observer { words ->
// Update the cached copy of the words in the adapter.
words?.let { adapter.setWords(it) }
})
val fab = findViewById<FloatingActionButton>(R.id.fab)
fab.setOnClickListener {
val intent = Intent(this#MainActivity, NewWordActivity::class.java)
startActivityForResult(intent, newWordActivityRequestCode)
}
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == newWordActivityRequestCode && resultCode == Activity.RESULT_OK) {
data?.getStringExtra(NewWordActivity.EXTRA_REPLY)?.let {
val word = Word(it)
wordViewModel.insert(word)
}
} else {
Toast.makeText(
applicationContext,
R.string.empty_not_saved,
Toast.LENGTH_LONG).show()
}
}
}

onClick not working in MVVM with DataBinding

For some reason, onClick isn't being registered with my adapter. I'm using the MVVM pattern and I've made sure that all the pieces are tied together but for the life of me I can't figure out why this won't work.
StoreFragment
package com.example.brandroidtest.main
import android.os.Bundle
import android.util.Log
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProviders
import androidx.navigation.fragment.findNavController
import com.example.brandroidtest.databinding.FragmentStoreBinding
class StoreFragment : Fragment() {
//Will Create a ViewModelProivders object of class DetailViewModel the first time viewModel is used
//Allows us to move this code from on create to the declaration
private val viewModel: StoreViewModel by lazy {
val factory = StoreViewModelFactory(requireNotNull(activity).application)
ViewModelProviders.of(this, factory).get(StoreViewModel::class.java)
}
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
Log.i("onCreateView", "StoreFragment created")
val binding = FragmentStoreBinding.inflate(inflater)
binding.setLifecycleOwner(this)
binding.viewModel = viewModel
binding.storeList.adapter = StoreAdapter(StoreAdapter.OnClickListener {
viewModel.displayStoreDetails(it)
Log.i("inside OnClickListener", "after displayDetails")
})
Log.i("between adapter.onclick", "and viewModel observe")
viewModel.selectedStore.observe(this, Observer {
Log.i("observe", "inside the selectedStore observe method")
if (null != it) {
this.findNavController().navigate(
StoreFragmentDirections.actionMainListFragmentToDetailFragment(
it
)
)
viewModel.displayStoreDetailsComplete()
}
})
return binding.root
}
}
StoreViewModel
package com.example.brandroidtest.main
import android.app.Application
import android.content.Context
import android.net.ConnectivityManager
import android.util.Log
import androidx.lifecycle.AndroidViewModel
import androidx.lifecycle.LiveData
import androidx.lifecycle.MutableLiveData
import com.example.brandroidtest.model.Store
import com.example.brandroidtest.network.StoreAPI
import kotlinx.coroutines.*
enum class StoreAPIStatus {LOADING, DONE, NO_CONNECTION}
class StoreViewModel(application: Application) : AndroidViewModel(application) {
// Response from server: Either Store Data or Failure Message
private val _status = MutableLiveData<StoreAPIStatus>()
// for status of get request
//displayed when there is no internet connection or if the connection is unstable and the data is being loaded
val status: LiveData<StoreAPIStatus>
get() = _status
//internal variable accessed within this file
private val listOfStores = MutableLiveData<List<Store>>()
//external variable for anywhere else
val stores: LiveData<List<Store>>
get() = listOfStores
private val _selectedStore = MutableLiveData<Store>()
val selectedStore: LiveData<Store>
get() = _selectedStore
private var viewModelJob = Job()
private val coroutineScope = CoroutineScope(viewModelJob + Dispatchers.Main)
/**
* Call getStoreData() in init so we can display the result immediately.
*/
init {
Log.i("viewModel init", "inside StoreViewModel init block")
if (isNetworkConnected(application.applicationContext))
getStoreData()
else
// Log.i("Bypassed network call", "")
listOfStores.value = emptyList()
_status.value = StoreAPIStatus.NO_CONNECTION
}
/**
* Sets the value of the status LiveData to the Store API data.
*/
private fun getStoreData() {
Log.i("getStoreData()", " inside getStoreData")
coroutineScope.launch {
try {
Log.i("getStoreData()", "Inside the coroutine before getData")
_status.value = StoreAPIStatus.LOADING
var storeData = async { StoreAPI.retrofitService.getData().stores }.await()
Log.i("getStoreData()", "Inside the coroutine after getData")
_status.value = StoreAPIStatus.DONE
listOfStores.value = storeData
} catch (e: Exception) {
_status.value = StoreAPIStatus.NO_CONNECTION
listOfStores.value = ArrayList()
e.printStackTrace()
}
}
}
override fun onCleared() {
super.onCleared()
viewModelJob.cancel()
}
private fun isNetworkConnected(context: Context): Boolean {
val cm =
context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
return cm!!.activeNetworkInfo != null && cm.activeNetworkInfo.isConnected
}
//will be called to set the store as the one that was clicked
fun displayStoreDetails(store : Store){
Log.i("displayStoreDetails", "inside this method")
_selectedStore.value = store
}
//sets the selected store's value to null so that live data can be updated when we select a new store and not show us the detail apge of the same store
fun displayStoreDetailsComplete() {
Log.i("displayStoreDetailsComplete", "inside this method")
_selectedStore.value = null
}
}
StoreAdapter
package com.example.brandroidtest.main
import android.util.Log
import android.view.LayoutInflater
import android.view.ViewGroup
import androidx.recyclerview.widget.DiffUtil
import androidx.recyclerview.widget.ListAdapter
import androidx.recyclerview.widget.RecyclerView
import com.example.brandroidtest.model.Store
import com.example.brandroidtest.databinding.ListItemBinding
class StoreAdapter(val onClickListener: OnClickListener) :
ListAdapter<Store, StoreAdapter.StoreViewHolder>(DiffCallback) {
class StoreViewHolder(private var binding: ListItemBinding) :
RecyclerView.ViewHolder(binding.root) {
fun bind(store: Store) {
binding.store = store
Log.i("Adapter bind", store.storeLogoURL)
binding.executePendingBindings()
}
}
companion object DiffCallback : DiffUtil.ItemCallback<Store>() {
override fun areItemsTheSame(oldItem: Store, newItem: Store): Boolean {
return oldItem === newItem
}
override fun areContentsTheSame(oldItem: Store, newItem: Store): Boolean {
return oldItem.storeID == newItem.storeID
}
}
override fun onCreateViewHolder(
parent: ViewGroup,
viewType: Int
): StoreViewHolder {
return StoreViewHolder(ListItemBinding.inflate(LayoutInflater.from(parent.context)))
}
override fun onBindViewHolder(holder: StoreViewHolder, position: Int) {
val store = getItem(position)
Log.i("inside onBindViewHolder", "")
holder.itemView.setOnClickListener {
Log.i("inside onBindViewHolder", "setOnClickListener")
onClickListener.onClick(store)
}
holder.bind(store)
}
class OnClickListener(val clickListener: (store: Store) -> Unit) {
fun onClick(store: Store) {
Log.i("inside onClick", "click is being registered ${store.city}")
return clickListener(store)
}
}
}
StoreDetailFragment
package com.example.brandroidtest.detailed
import android.os.Bundle
import androidx.fragment.app.Fragment
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.lifecycle.ViewModelProvider
import androidx.lifecycle.ViewModelProviders
import com.example.brandroidtest.R
import com.example.brandroidtest.databinding.FragmentStoreDetailBinding
/**
* A simple [Fragment] subclass.
*/
class StoreDetailFragment : Fragment() {
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val application = requireNotNull(activity).application
val binding = FragmentStoreDetailBinding.inflate(inflater)
binding.setLifecycleOwner(this)
val store = StoreDetailFragmentArgs.fromBundle(arguments!!).selectedStore
val viewModelFactory = StoreDetailViewModelFactory(store, application)
binding.viewModel = ViewModelProviders.of(this, viewModelFactory).get(StoreDetailViewModel::class.java)
return binding.root
}
}
StoreDetailViewModel
package com.example.brandroidtest.detailed
import android.app.Application
import androidx.lifecycle.AndroidViewModel
import androidx.lifecycle.LiveData
import androidx.lifecycle.MutableLiveData
import com.example.brandroidtest.model.Store
class StoreDetailViewModel(store: Store, application: Application) : AndroidViewModel(application) {
private val _selectedStore = MutableLiveData<Store>()
val selectedStore : LiveData<Store>
get() = _selectedStore
init {
_selectedStore.value = store
}
}
I have no idea why onClick won't work and the Detail Fragment won't show because of it
Here is the project link: https://drive.google.com/open?id=1m8R8HvCt4m0KIp_IwdeO1YdB5yY8A8LK

The issue come from your adapter item layout.
The height of every item show be wrap_content. But you are using a ScrollView as the root view of your item view.
Remove the useless ScrollView and also the next LinearLayout. You layout should become like this:
<LinearLayout
...
android:padding="16dp"/>
<ImageView
android:id="#+id/store_logo"
.../>
<LinearLayout
android:id="#+id/store_detail"
...>
</LinearLayout>

Adapter doesn't load my Room db list

I was following some guide and tweaking variable name to fit my own project. My problem was most people dont appears to load from Room db into an adapter so when trying to do upon opening the apps my view appears empty. while i checked the DB using DB browser for SQLite i can see my db contain 7 items.
Main activity
package com.example.android.budgetproject
import android.arch.persistence.room.RoomDatabase
import android.content.Context
import android.content.SharedPreferences
import android.databinding.DataBindingUtil
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.os.Handler
import com.example.android.budgetproject.databinding.ActivityMainBinding
import com.example.android.budgetproject.popUp.DepenseDetails
import com.example.android.budgetproject.popUp.NewBudget
class MainActivity : AppCompatActivity(), SharedPreferences.OnSharedPreferenceChangeListener, BudgetVM.NewButtonClick {
lateinit var budget : SharedPreferences
var budgetTotal: String? = null
val vm = BudgetVM()
lateinit var db: RoomDatabase
lateinit var adapter: TransactionAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
val binding = DataBindingUtil.setContentView<ActivityMainBinding>(this, R.layout.activity_main)
binding.vm = vm
//Get the Total Budget in the shared pref and display it
budget = getSharedPreferences("Budget", Context.MODE_PRIVATE)
budget.registerOnSharedPreferenceChangeListener(this)
budgetTotal = budget.getString("BudgetTotal", null)
adapter = TransactionAdapter()
//Open Dialog if new user.
if(budgetTotal == null) {
NewBudget.createPopUp(this)
} else {
vm.budgetTotal.set(budgetTotal)
}
vm.listener = this
//Room
db = MyDatabase.getInstance()
//Adapter
val handler = Handler()
Thread({
val transactionFromDb = MyDatabase.mInstance?.transactionDao()?.getAllTransaction()
handler.post({
if (transactionFromDb != null) adapter.addTransaction(transactionFromDb)
})
}).start()
adapter.notifyDataSetChanged()
}
override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences?, key: String?) {
vm.budgetTotal.set(budgetTotal)
}
override fun newTransactionClicked(){
DepenseDetails.createTransaction(this)
}
}
The Dao:
package com.example.android.budgetproject
import android.arch.persistence.room.*
import com.example.android.budgetproject.Transaction
import android.arch.persistence.room.Delete
import android.arch.persistence.room.Dao
#Dao
interface TransactionDao {
#Query("SELECT * FROM `transaction`")
fun getAllTransaction(): List<Transaction>
#Query("SELECT * FROM `transaction` where uid IN (:transactionId)")
fun findTransactionById(transactionId: IntArray): List<Transaction>
#Insert(onConflict = 1)
fun insertTransaction(transaction: Transaction)
#Delete
fun deleteTransaction(transaction: Transaction)
}
The Adapter:
package com.example.android.budgetproject
import android.support.v7.recyclerview.extensions.ListAdapter
import android.support.v7.widget.RecyclerView
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import kotlinx.android.synthetic.main.activity_main.view.*
import kotlinx.android.synthetic.main.row_depense_fragment.view.*
/**
* Created by olivier on 2018-03-13.
*/
class TransactionAdapter(private val clickListener: ButtonClick? = null):
ListAdapter<Transaction, TransactionAdapter.ViewHolder>(TransactionDiffCallback()) {
interface ButtonClick{
fun clicked(id: Int)
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val inflater = LayoutInflater.from(parent.context)
return ViewHolder(inflater.inflate(R.layout.row_depense_fragment, parent, false))
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.bind(getItem(position))
}
inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView){
fun bind(transaction: Transaction){
itemView.tv_depense_description.text = transaction.description
itemView.tv_depense.text = transaction.depense
itemView.tv_depense_date.text = transaction.date
itemView.setOnClickListener{
clickListener?.clicked(adapterPosition)
}
}
}
private var transactionList = ArrayList<Transaction>()
fun addTransaction(list: List<Transaction>){
transactionList.clear()
transactionList.addAll(list)
notifyDataSetChanged()
}
}
And the util i use to create DB item.
package com.example.android.budgetproject
import android.os.AsyncTask
import android.widget.Toast
class TransactionCreation {
fun transactionCreation(depense: String, description: String, date: String){
val newTransaction = Transaction(depense, description, date)
val db = MyDatabase
object : AsyncTask<Void, Void, Void>() {
override fun doInBackground(vararg params: Void?): Void? {
db.getInstance().transactionDao().insertTransaction(newTransaction)
return null
}
override fun onPostExecute(result: Void?) {
super.onPostExecute(result)
Toast.makeText(BudgetApplication.getContext(), "Transaction saved", Toast.LENGTH_SHORT)
}
}.execute()
}
}
Here's also a link to the project github should be up to date.
https://github.com/OlivierLabelle/BudgetProject
Thanks for checking.

Set notifyDataSetChanged within the thread in your MainActivity via the handler.