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Android: How to reference to an outside View, in RecyclerView

Hi I have an simple app with Bottom Navigation Activity. In Home Fragment I have a Button called Fruits. It opens a PopupWindow. In the popup is a RecyclerView with 4 Buttons(fruits names).
I want, when I press on a Button in the PopupWindow, to change the name of Button(called Fruits) form home_fragment, in whatever fruit was chosen.
HomeFragment:
class HomeFragment : Fragment() {
private var _binding: FragmentHomeBinding? = null
private val binding get() = _binding!!
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
_binding = FragmentHomeBinding.inflate(inflater, container, false)
val root: View = binding.root
return root
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
binding.Fruits.setOnClickListener {
show_popup(requireContext(), view, R.layout.fruits_popup)
}
}
override fun onDestroyView() {
super.onDestroyView()
_binding = null
}
fun show_popup(c: Context, v: View, l: Int){
val popup_window = PopupWindow(c)
val inflater = layoutInflater.inflate(l, null)
val recyclerView: RecyclerView = inflater.findViewById(R.id.recycler_view)
recyclerView.layoutManager = LinearLayoutManager(context)
recyclerView.adapter = FruitsAdapter()
popup_window.contentView = inflater
popup_window.isFocusable = true
popup_window.isOutsideTouchable = true
popup_window.showAtLocation(v, Gravity.CENTER, 0, 0)
}
}
FruitsAdapter:
class FruitsAdapter : RecyclerView.Adapter<FruitsAdapter.FruitsViewHolder>() {
private val list = listOf<String>("Banana", "Orange", "Apple", "Watermelon")
class FruitsViewHolder(val view: View): RecyclerView.ViewHolder(view) {
val button = view.findViewById<Button>(R.id.fruit)
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): FruitsViewHolder {
val layout = LayoutInflater.from(parent.context).inflate(R.layout.fruit, parent, false)
return FruitsViewHolder(layout)
}
override fun onBindViewHolder(holder: FruitsViewHolder, position: Int) {
val item = list.get(position)
holder.button.text = item.toString()
}
override fun getItemCount(): Int {
return list.size
}
}
fragment_gome.xml
<?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"
tools:context=".ui.home.HomeFragment">
<Button
android:id="#+id/Fruits"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Fruits"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.498"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.254" />
</androidx.constraintlayout.widget.ConstraintLayout>
fruits_popup.xml:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout 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"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/recycler_view"/>
</FrameLayout>
fruit.xml
<?xml version="1.0" encoding="utf-8"?>
<Button xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/fruit"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="4dp"
android:padding="8dp" />

Try to google with keyword 'callback' bro

How Can I achieve this layout by using the recycler view in android?? when I was passing list of String image url to the adapter ? layout in Image

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strong text
[2]: https://i.stack.imgur.com/YJOpm.png
activity_main
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#170628"
android:orientation="vertical"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rv_images"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
image_layout.xml
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto">
<androidx.cardview.widget.CardView
android:layout_width="100dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:layout_margin="5dp"
app:cardCornerRadius="10dp"
android:layout_height="100dp">
<ImageView
android:id="#+id/big_image"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:src="#drawable/zone_images" />
</androidx.cardview.widget.CardView>
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity
class MainActivity : AppCompatActivity() {
private lateinit var zoneBinding: ActivityMainBinding
var image = ArrayList<String>()
lateinit var zoneAdapter:ZoneImagesAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
zoneBinding= DataBindingUtil.setContentView(this,R.layout.activity_main)
buildData()
setRecyclerView()
}
private fun buildData() {
image.add("https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQzx__blVU5FWJAUCU4d9-E095_n3Fgy1tuxA&usqp=CAU")
image.add("https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQh90iDDn5BoUnZqANXUszd17_Q-RhfRo8V6Q&usqp=CAU")
image.add("https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQzx__blVU5FWJAUCU4d9-E095_n3Fgy1tuxA&usqp=CAU")
image.add("https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQh90iDDn5BoUnZqANXUszd17_Q-RhfRo8V6Q&usqp=CAU")
image.add("https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQzx__blVU5FWJAUCU4d9-E095_n3Fgy1tuxA&usqp=CAU")
image.add("https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQh90iDDn5BoUnZqANXUszd17_Q-RhfRo8V6Q&usqp=CAU")
}
private fun setRecyclerView() {
zoneAdapter = ZoneImagesAdapter(image)
val flexboxLayoutManager = FlexboxLayoutManager(this)
flexboxLayoutManager.flexDirection =FlexDirection.ROW
flexboxLayoutManager.flexWrap = FlexWrap.WRAP
flexboxLayoutManager.justifyContent = JustifyContent.CENTER
flexboxLayoutManager.alignItems = AlignItems.STRETCH
zoneBinding.rvImages.apply {
adapter=zoneAdapter
layoutManager=flexboxLayoutManager
}
}
Adapter
class ZoneImagesAdapter (var listOfImageUrl:ArrayList<String>):
RecyclerView.Adapter<ZoneImagesAdapter.ImageViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ImageViewHolder {
val view: View = LayoutInflater.from(parent.context)
.inflate(R.layout.big_image_layout, parent, false)
return ImageViewHolder(view)
}
override fun onBindViewHolder(holder: ImageViewHolder, position: Int) {
val image = listOfImageUrl[position]
holder.setImages(image)
}
override fun getItemCount(): Int {
return listOfImageUrl.size
}
class ImageViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
var zoneImage:ImageView=itemView.findViewById(R.id.big_image)
fun setImages(images: String) {
Glide.with(zoneImage).load(images).into(zoneImage)
val layoutParams:ViewGroup.LayoutParams = zoneImage.layoutParams
if (layoutParams is FlexboxLayoutManager.LayoutParams){
val flexboxLp:FlexboxLayoutManager.LayoutParams= layoutParams as FlexboxLayoutManager.LayoutParams
flexboxLp.flexGrow= 1.0f
}
}
}
}
How can I achieve this layout that is showing inside image using recyclerView, ?? I use flexboxLayoutManager for this but I do not know how can I used, Can anyone help me to make this layout that is showing inside image

E/RecyclerView: No adapter attached; skipping layout Kotlin Android

I have created a fragment and inside that fragment I have a recyclerview but when my fragment is loaded nothing shows and it give me this error "E/RecyclerView: No adapter attached; skipping layout". Below is the code for the adapter and fragment class, any help would be appreciated
Adapter Class:
class ViewAllRecipeAdapter(private val newList: ArrayList<Recipes>) :
RecyclerView.Adapter<ViewAllRecipeAdapter.MyViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val itemView = LayoutInflater.from(parent.context).inflate(R.layout.view_all_recipe_item, parent, false)
return MyViewHolder(itemView)
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
val currentItem = newList[position]
holder.recipeName.text = currentItem.recipeName
holder.recipeDesc.text = currentItem.recipeDescription
}
override fun getItemCount(): Int {
return newList.size
}
class MyViewHolder(itemview: View) : RecyclerView.ViewHolder(itemview) {
val recipeName: TextView
val recipeDesc: TextView
init {
recipeName = itemView.findViewById<View>(R.id.recipe_name) as TextView
recipeDesc = itemView.findViewById<View>(R.id.recipe_description) as TextView
}
}
}
Fragment Class:
class ViewAllMyRecipesFragment : Fragment() {
private lateinit var recyclerview: RecyclerView
private lateinit var recipeData: ArrayList<Recipes>
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val view: View = inflater.inflate(R.layout.fragment_view_all_my_recipes, container, false)
recipeData = dummygenerator(10)
recyclerview = view.findViewById<RecyclerView>(R.id.recycler_view_all_recipes)
recyclerview.adapter = ViewAllRecipeAdapter(recipeData)
recyclerview.layoutManager = LinearLayoutManager(view.context)
recyclerview.setHasFixedSize(true)
// Inflate the layout for this fragment
return view
}
private fun dummygenerator(size: Int) : ArrayList<Recipes>{
val list = ArrayList<Recipes>()
for(i in 0 until size) {
val drawable = when (i % 3) {
0 -> "recipeName " +i
1 -> "recipeDescription " + i
else -> "Else " +i
}
val item = Recipes("title $i", "body")
list += item
}
return list
}
}
fragment_view_all_my_recipes.xml
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".ui.recipe.ViewAllMyRecipesFragment">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycler_view_all_recipes"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:listitem="#layout/view_all_recipe_item" />
</androidx.constraintlayout.widget.ConstraintLayout>
view_all_recipe_item.xml
<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="wrap_content">
<ImageView
android:id="#+id/recipe_image"
android:layout_width="80dp"
android:layout_height="80dp"
android:layout_marginEnd="331dp"
android:layout_marginBottom="651dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:srcCompat="#tools:sample/avatars" />
<TextView
android:id="#+id/recipe_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="25dp"
android:text="TextView"
android:textStyle="bold"
android:textSize="18sp"
app:layout_constraintStart_toEndOf="#+id/recipe_image"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/recipe_description"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="32dp"
android:layout_marginTop="10dp"
android:text="TextView"
app:layout_constraintStart_toEndOf="#+id/recipe_image"
app:layout_constraintTop_toBottomOf="#+id/recipe_name" />
</androidx.constraintlayout.widget.ConstraintLayout>

Try moving all onCreateView logic to onViewCreated and
recyclerview.layoutManager = LinearLayoutManager(requireActivity())
recyclerview.adapter = ViewAllRecipeAdapter(recipeData)
because sometimes it causes problem when layoutManager is after adapter.

Android recyclerView problem - multi-layer scrolling content?

I am brand new in Android/kotlin development. I created my very first app with a recyclerView to display the folders and files of the phone. I put the recyclerView into a segment, created my data structure and adapter. Assembled together. It works - or seems to work. But the problem is that when I try to scroll the list, the initial state remains "ther" and the list content starts to scroll. Like it was two different layers. I have no clue where to find the problem. Never heard about such a bug like this. Please give me advice, some keywords where to dig and find the solution. Thanks!
class BrowseFileFragment : Fragment() {
private lateinit var attachedCtx : Context
override fun onAttach(context: Context) {
super.onAttach(context)
this.attachedCtx = context
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,savedInstanceState: Bundle?): View?
{
var view : View = inflater.inflate(R.layout.fragment_browse_file, container, false)
val modelFactory = FileBrowseModelFactory()
val data = modelFactory.create()
bindModelToView(data, view)
return view
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
}
private fun bindModelToView(data: BrowseSettings, view: View)
{
var adapter = MyFileAdapter(data.FoldersAndFiles, this.attachedCtx)
var recyclerView = view.findViewById<RecyclerView>(R.id.fileItemView)
var linearLayoutManager = LinearLayoutManager(this.attachedCtx)
recyclerView.layoutManager = linearLayoutManager
recyclerView.adapter = adapter
var folderLabel = view.findViewById<TextView>(R.id.folderName)
folderLabel.text = data.CurrentFolder
}
}
The segment layout
<?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"
tools:context=".BrowseFileFragment">
<TextView
android:id="#+id/folderName"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="5dp"
android:text="#string/hello_first_fragment"
android:textAlignment="viewStart"
android:textAppearance="#style/TextAppearance.AppCompat.Display1"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/fileItemView"
android:layout_width="match_parent"
app:layout_constrainedHeight="true"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="#+id/folderName"
app:layout_constraintStart_toStartOf="#+id/folderName"
app:layout_constraintTop_toBottomOf="#+id/folderName" />
</androidx.constraintlayout.widget.ConstraintLayout>
The list line layout
<?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="60dp">
<TextView
android:background="#color/cardview_shadow_start_color"
android:id="#+id/itemName"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toTopOf="parent"
android:padding="5dp"
android:textSize="30dp"
android:textStyle="bold" />
</androidx.constraintlayout.widget.ConstraintLayout>
And finally my adapter:
class MyFileAdapter(private val items: List<FileItem>, private val context: Context)
: RecyclerView.Adapter<MyFileAdapter.MyViewHolder>()
{
class MyViewHolder (itemView: View) :RecyclerView.ViewHolder(itemView), View.OnClickListener {
init {
itemView.setOnClickListener(this)
}
fun bindItem(f: FileItem) {
var name: TextView = itemView.findViewById(R.id.itemName) as TextView
name.text = f.Name
}
}
override fun getItemCount() = items.size
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val view = LayoutInflater
.from(context)
.inflate(R.layout.recyclerview_filteitem_row, parent, false)
return MyViewHolder(view)
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
var item = items\[position\]
holder!!.bindItem( item )
}
}

It found out that as the whole list view is saved as a segment, this segment loads "automatically" and was loaded programatically also, and the two "loads" causes this thing. :( Thanks for your time guys.

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!