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How to display an empty item of recyclerview so that user can fill the data into it?

I am new to kotlin-android and I am developing a stock keeping unit, where in one fragment i need to load the data into recycler view using arraylist but also, i need one blank item, where user can enter his own data and once he fills that blank item, a new blank item should be created.
class RecyclerViewAdapterU (val dataList:ArrayList<ModelClass>): RecyclerView.Adapter<RecyclerViewAdapterU.ViewHolder>() {
var _binding: UploadItemViewBinding? = null
val binding get() = _binding!!
override fun onCreateViewHolder(
parent: ViewGroup,
viewType: Int
): RecyclerViewAdapterU.ViewHolder {
val v =
LayoutInflater.from(parent.context).inflate(R.layout.upload_item_view, parent, false)
_binding = UploadItemViewBinding.bind(v)
return ViewHolder(binding.root)
}
fun getUpdatedDetails(skucode:String,pos:Int){
// val skuDetails:ArrayList<ModelClass>
val call: Call<List<ModelClass>>? =
ApiClient.instance?.myApi?.getfromsku(skucode)!!
call!!.enqueue(object : Callback<List<ModelClass>?> {
override fun onResponse(
call: Call<List<ModelClass>?>,
response: Response<List<ModelClass>?>
) {
if (!response.body().isNullOrEmpty()) {
val skuDetails: ArrayList<ModelClass> = response.body() as ArrayList<ModelClass>
//
// if (!skuDetails.isNullOrEmpty()) {
val x = dataList[pos].sku_code
if (skuDetails[pos].sku_code != x) {
//for (i in skuDetails.indices){
println(skuDetails[pos].sku_code)
println(".........$pos")
dataList.removeAt(pos)
dataList.add(pos, skuDetails[0])
skuDetails.clear()
notifyItemChanged(pos)
//}
}
}
}
override fun onFailure(call: Call<List<ModelClass>?>, t: Throwable) {
}
})
}
override fun onBindViewHolder(holder: ViewHolder, #SuppressLint("RecyclerView") position: Int) {
bindItems(dataList[position])
holder.getStock()
holder.updateStockDetail()
}
fun bindItems(data: ModelClass) {
binding.apply {
itemquant.text=data.item_quant
uploadItemName.text = data.item_name
uploadMfg.text = data.mfg
skuStock.setText(data.item_stock.toString())
skuCode.setText(data.sku_code)
}
}
override fun getItemCount(): Int {
return dataList.size
}
inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
fun getStock() {
binding.skuStock.addTextChangedListener(object : TextWatcher {
override fun beforeTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {}
override fun onTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {}
override fun afterTextChanged(editable: Editable) {
if (binding.skuStock.isFocused){
for (i in 0 until RecyclerViewAdapter.ob.dataSelected.size){
if (editable.toString().trim()!=""){
var x= editable.toString().trim().toInt()
RecyclerViewAdapter.ob.dataSelected[adapterPosition].item_stock=x
//getting current itemstock before pushing update.
//assigning latest itemstock to the data for the update
}
}
}}
})
}
fun updateStockDetail(){
binding.skuCode.addTextChangedListener(object : TextWatcher{
override fun beforeTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {}
override fun onTextChanged(charSequence: CharSequence, i: Int, i1: Int, i2: Int) {
}
override fun afterTextChanged(editable: Editable) {
//binding.skuCode.removeTextChangedListener(this)
var pos:Int=adapterPosition
var x= editable.toString().trim()
//RecyclerViewAdapter.ob.dataSelected[adapterPosition].sku_code=x
println("$x in textwatcher and $pos")
//getting edited text and calling the function to get updated details.
getUpdatedDetails(x,pos)
// binding.skuCode.addTextChangedListener(this)
}
})
}
}
}
I have couple of bugs in the adapter too, for example, i cant change textwatcher more than once.
If somebody could help me with this, would be very glad.
ob.data.selected comes from another recyclerview adapter.

One way you can do this is by using a different view type for the blank item that will always stay at the very top (or bottom if you prefer). Once the blank item is filled up then a new non-blank item with a different view type will be added to your list.
More info about view types here: Android and Kotlin: RecyclerView with multiple view types

Another "RecyclerView duplicating items" question

I'm having this problem and spent hours exploring different solutions found here but couldn't figure it out. I have a RecyclerView with a RadioGroup (with two RadioButton) and an EditText. As expected, the text keeps getting duplicated on scroll and the "original" gets deleted. The same happens with the radio buttons. I've tried to save on another array backup the values when the view is recycled but couldn't solve the duplicating issue.
Here's my adapter
class ServicesCheckoutAdapter(var context: Context,
var servicesList: List<Service>) : RecyclerView.Adapter<ServicesCheckoutAdapter.ViewHolder>() {
private lateinit var onRadioGroupClickListener: OnRadioGroupClickListener
private lateinit var onTextChangedListener: OnTextChangedListener
private lateinit var onServiceClickListener: OnServiceClickListener
private var externalArray = mutableListOf<String>()
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val view = LayoutInflater.from(context).inflate(R.layout.services_list_item,
parent, false)
val viewHolder = ViewHolder(view)
val position = viewHolder.adapterPosition
view.setOnClickListener {
if (onServiceClickListener != null) {
onServiceClickListener.onServiceClick(view, servicesList[position].id, position)
}
}
return viewHolder
}
override fun getItemId(position: Int): Long {
return super.getItemId(position)
}
override fun getItemViewType(position: Int): Int {
return super.getItemViewType(position)
}
interface OnServiceClickListener {
fun onServiceClick(view: View, serviceId: Int, position: Int)
}
fun setOnServiceClickListener(listener: OnServiceClickListener)
{
onServiceClickListener = listener
}
interface OnRadioGroupClickListener {
fun onRadioGroupClick(buttonId: Int, serviceId: Int, position: Int) {}
}
fun setOnRadioButtonClickListener(listener: OnRadioGroupClickListener) {
onRadioGroupClickListener = listener
}
interface OnTextChangedListener{
fun onTextChanged(position: Int, text: String)
}
fun setOnTextChangedListener(listener: OnTextChangedListener){
onTextChangedListener = listener
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
Log.d("recycler", "lista: ${servicesList[position].serviceSolution}")
holder.edtSolution.removeTextChangedListener(holder.watcher)
holder.bind(context,
servicesList[position].id,
servicesList[position].name,
servicesList[position].serviceSolved,
servicesList[position].serviceSolution,
onRadioGroupClickListener,
onTextChangedListener,
position)
}
override fun getItemCount(): Int {
return servicesList.size
}
class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
var radioGroup = itemView.findViewById<RadioGroup>(R.id.radioGroupService)
val edtSolution = itemView.findViewById<EditText>(R.id.editTextCheckoutDesc)
var watcher: TextWatcher? = null
fun bind(context: Context,
serviceId: Int,
serviceName: String,
serviceSolved: Boolean,
serviceSolution: String,
onRadioGroupClickListener: OnRadioGroupClickListener,
onTextChangedListener: OnTextChangedListener,
position: Int
) {
itemView.findViewById<TextView>(R.id.serviceTitle)
.text = context.resources
.getString(R.string.service_title_comma, serviceName)
itemView.findViewById<RadioGroup>(R.id.radioGroupService)
.setOnClickListener {
onRadioGroupClickListener
.onRadioGroupClick(
(it as RadioGroup).checkedRadioButtonId, serviceId, adapterPosition)
}
if (serviceSolved) {
radioGroup.find<RadioButton>(R.id.radioBtnYes).isChecked = true
radioGroup.find<RadioButton>(R.id.radioBtnNo).isChecked = false
} else {
radioGroup.find<RadioButton>(R.id.radioBtnYes).isChecked = false
radioGroup.find<RadioButton>(R.id.radioBtnNo).isChecked = true
}
edtSolution.addTextChangedListener(object: TextWatcher{
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
onTextChangedListener.onTextChanged(position, s.toString())
}
override fun afterTextChanged(s: Editable?) {
}
})
}
}
}
And here's the adapter initialization on the activity
serviceList = occurrence.services
servicesAdapter = ServicesCheckoutAdapter(this, serviceList)
recyclerViewServices.adapter = servicesAdapter
recyclerViewServices.layoutManager = LinearLayoutManager(this)
servicesAdapter.setOnRadioButtonClickListener(object : ServicesCheckoutAdapter.OnRadioGroupClickListener {
override fun onRadioGroupClick(buttonId: Int, serviceId: Int, position: Int) {
super.onRadioGroupClick(buttonId, serviceId, position)
when (buttonId) {
R.id.radioBtnYes -> {
serviceList[position].serviceSolved = true
servicesAdapter.notifyDataSetChanged()
}
R.id.radioBtnNo -> {
serviceList[position].serviceSolved = false
servicesAdapter.notifyDataSetChanged()
}
}
}
})
servicesAdapter.setOnTextChangedListener(object : ServicesCheckoutAdapter.OnTextChangedListener{
override fun onTextChanged(position: Int, text: String) {
serviceList[position].serviceSolution = text
}
})

RecyclerView isn't usually made for Input views. As Android saves the input of a view depending on its ID, your RecyclerView has X number of views that all have the same ID, hence they all use the same state.
A solution to this would be saving your input state manually in recycle method, and restoring it in bind method.
So if you have 20 items, you have 20 states. Initially they are all empty or defaulted, and change when needed to save.
A more simpler approach would be using a LinearLayout or similar Layouts to accomplish your goal, but that depends on how many items you have and how many views that will contain.
You still need to be careful for the View ID part, though

I've tried to use a ListView but the keyboard went crazy changing focus. Decided to keep the RecyclerView and since my dynamic list isn't so large, I used the
holder.setIsRecyclable(false);
on the OnBindViewHolder() method and it solved my issue. Thanks everyone for the help

Filter list of product in a recyclerview - android

So I have a list of product in my recyclerview. Have a editText for search term .
Each time user type something in the editText field the list must be filtered .
with live search there is no problem and the process work well .
for better ui experience I created a button(btn_search) for the edittext also. But in this case when click on the button the list not filtered and just disappeared .!!!
what is wrong with my code.
Code :
this is function in the adapter that calls datachanged :
ListAdapter :
fun filterList(filtername : List<Model>) {
this.model = filtername
notifyDataSetChanged()
}
activity :
lateinit var editText: EditText
lateinit var model: ArrayList<Model>
lateinit var adapter: ListAdapter
lateinit var button: Button
lateinit var recyclerView: RecyclerView
button = findViewById(R.id.btn_search)
var list = ArrayList<Model>()
list.add(somedata) ...
recyclerView = findViewById(R.id.recyclerView)
model = list
recyclerView.layoutManager = GridLayoutManager(this#MainActivity, 2)
adapter = ListAadapter(model)
recyclerView.adapter = adapter
editText = findViewById(R.id.edit_text_search)
// this is where call btnsearch but the list not filtered and disappeared
button.setOnClickListener {
filter(editText.toString())
}
// with this live search there is no issue and list filtered
/*
editText.addTextChangedListener(object : TextWatcher {
override fun afterTextChanged(text: Editable?) {
filter(text.toString())
}
override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
}
override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
}
})*/
// this is the function for filter the list
fun filter(text: String) {
val filterNameList = ArrayList<Model>()
model.filterTo(filterNameList) { model ->
model.title.contains(text)
}
adapter.filterList(filterNameList)
}
So any idea where I'm doing wrong ?

Seems like you are not getting the EditText text, you are casting the EditText directly into string in this line
button.setOnClickListener {
filter(editText.toString())
}
So, you need to change it to this
button.setOnClickListener {
filter(editText.text.toString())
}

Android Adapter redrawing view with all the same original items rather than removing selected item

I've been trying to delete an item from my list so that it updates without the removed item, but the list seems to redraw itself and keeps displaying all the original items as before. For a short bit of time it's possible to see the item as if it's being removed, however, due to this redrawing everything gets back to what it was before the removal.
I've tried several combinations of the following methods but none of them seem to work in this case.
adapter.notifyItemRangeChanged(position, adapter.itemCount)
adapter.notifyItemRemoved(position)
adapter.notifyItemChanged(position)
adapter.notifyDataSetChanged()
These are my files. Please notice I'm using the Groupie library as a replacement for the default RecyclerView.
class RecyclerProductItem(
private val activity: MainActivity,
private val product: Product,
private val onItemClickListener: OnItemClickListener?
) : Item<GroupieViewHolder>() {
override fun bind(viewHolder: GroupieViewHolder, position: Int) {
viewHolder.apply {
with(viewHolder.itemView) {
ivTrash.setOnClickListener {
if (onItemClickListener != null) {
Toast.makeText(context, "delete method to be added here", Toast.LENGTH_SHORT).show()
onItemClickListener.onClick(viewHolder.adapterPosition)
// deleteProduct(product.id)
}
}
}
}
}
interface OnItemClickListener {
fun onClick(position: Int) //pass your object types.
}
override fun getLayout() = R.layout.recyclerview_item_row
}
And here my fragment:
class ProductsListFragment : Fragment() {
private lateinit var adapter: GroupAdapter<GroupieViewHolder>
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
return inflater.inflate(R.layout.fragment_products_list, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
val linearLayoutManager = LinearLayoutManager(activity)
recyclerView.layoutManager = linearLayoutManager
adapter = GroupAdapter()
recyclerView.adapter = adapter
loadProducts()
}
/**
* API calls
*/
private fun loadProducts() {
GetProductsAPI.postData(object : GetProductsAPI.ThisCallback,
RecyclerProductItem.OnItemClickListener {
override fun onSuccess(productList: List<JsonObject>) {
Log.i(LOG_TAG, "successful network call")
for (jo in productList) {
val gson = GsonBuilder().setPrettyPrinting().create()
val product: Product =
gson.fromJson(jo, Product::class.java)
adapter.add(
RecyclerProductItem(
activity as MainActivity,
Product(
product.id,
product.title,
product.description,
product.price
), this
)
)
}
}
override fun onClick(position: Int) {
Log.i(LOG_TAG, position.toString())
adapter.notifyItemRangeChanged(position,
adapter.itemCount)
adapter.notifyItemRemoved(position)
}
})
}
}
Many thanks.

Simple sample
class GroupAdapter(private val items: MutableList<Any>) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
fun removeByPosition(position: Int) {
items.removeAt(position)
notifyItemRemoved(position)
}

RecyclerView not auto scrolling to the top after updating adapter

I have a custom adapter, and filter that I am currently implementing to filter a recycler view based on a simple substring search on my recycler view entries. Here is my adapter NotifyChanged() function, which updates the RecylerView, and my custom filter() function. Everything works great, except for the auto scrolling afterwards.
private fun notifyChanged() {
val result = DiffUtil.calculateDiff(object : DiffUtil.Callback() {
override fun getOldListSize(): Int {
return objects.size
}
override fun getNewListSize(): Int {
return temp.size
}
override fun areItemsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
return this#DiffRecyclerViewAdapter.areItemsTheSame(objects[oldItemPosition], temp[newItemPosition])
}
override fun areContentsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
return this#DiffRecyclerViewAdapter.areContentsTheSame(objects[oldItemPosition], temp[newItemPosition])
}
})
objects.clear()
objects.addAll(temp)
result.dispatchUpdatesTo(this)
}
fun filter(text : String){
val ob = original_objects as ArrayList<Category>
val filtered_categories = ArrayList<T>() as ArrayList<Category>
for (category in ob){
//val temp_category = category
val list_of_subcategories = ArrayList<T>() as ArrayList<Category>
for (subcategory in category.categories){
val name_of_category = subcategory.name.toLowerCase()
if (name_of_category.contains(text)){
list_of_subcategories?.add(subcategory)
}
}
if (list_of_subcategories.size > 0){
val newCategory = Category(category.id,category.name,category.description,category.videos,list_of_subcategories)
filtered_categories.add(newCategory)
}
}
temp = filtered_categories as MutableList<T>
notifyChanged()
}
In my SearchActivity.kt I have the following listener:
searchEditText.addTextChangedListener(object : TextWatcher{
override fun afterTextChanged(s: Editable?) {}
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
adapter.filter(s.toString())
recyclerView.scrollToPosition(0)
}
})
I was looking through the source code of DiffUtil and notifyDataSetChanged() to see how scrolling after filtering works. But didn't have much luck. The whole problem is that after I search text the RecyclerView is filtered fine. But will scroll to inconsistent locations. I want it to scroll back to the top every single time, but this isn't happening. EVEN WITH scrollToPosition(0) it will USUALLY scroll to the top, but not always.
I thought scrolling to the top was typically automatic in this case. I'm curious as to what the best practice is in updating and scrolling.

It needs some time to update the data on recyclerview. Mean while you are trying to scroll which doesn't work in most of the cases. PReferably use a postDelayed with 200 or 300 milliseconds before scrolling
Ex:
new Handler.postDelayed(new Runnable(){
#Override
public void run(){
recyclerView.scrollToPosition(0)
}
}, 300);