Develop Reference

How to update recyclerview element and retrieve sum all updated elements

Updating value of recyclerview but unable to update corresponding data in model class
Model classes
#Parcelize
class GetStockListData : ArrayList<GetStockListDataItem>(), Parcelable
#Parcelize
data class GetStockListDataItem(
var Qty:#RawValue Double,
var selectedQty: Double
): Parcelable
able to change recyclerview element using alertbox as follows
private fun showAlertDialog(stockListData: GetStockListData, position: Int) {
val layoutInflater = LayoutInflater.from(context)
val customView =
layoutInflater.inflate(R.layout.change_qty_dialog, null)
val myBox: android.app.AlertDialog.Builder = android.app.AlertDialog.Builder(context)
myBox.setView(customView)
val dialog = myBox.create()
dialog.show()
val etQuantity = customView.findViewById<AppCompatEditText>(R.id.et_quantity)
if (stockListData[position].Qty < args.getListDetailsByRNumberModelItem.ReqQty) {
val df = DecimalFormat("#.##")
df.roundingMode = RoundingMode.CEILING
etQuantity.setText(df.format(stockListData[position].Qty).toString())
} else
etQuantity.setText(args.getListDetailsByRNumberModelItem.ReqQty.toString())
etQuantity.setSelection(etQuantity.text.toString().length)
etQuantity.requestFocus()
requireContext().showKeyboard()
customView.findViewById<Button>(R.id.btnDone).setOnClickListener {
if(!etQuantity.text.isNullOrEmpty()) {
val qtyStr = etQuantity.text.toString().trim()
var qtyDouble = qtyStr.toDouble()
stockListData[position].selectedQty = qtyDouble
adapter.notifyDataSetChanged()
dialog.dismiss()
}
}
}
for (i in 0 until stockListData.size){
sum += stockListData[i].selectedQty
}
here if user edit Recyclerview list item multiple times, each value added to list. Finally if i try to retrieve sum of all recyclerview elements getting wrong value because in model class values are added when i try to replace element.

Instead of passing whole list as parameter to showAlertDialog() method, you could just pass single item which has to be updated. And one more thing, you should not call adapter.notifyDataSetChanged() for single item updation, rather call adapter.notifyItemChanged(position). Look at below code, I am getting correct sum :
private fun showRecipeMeasureDialog(recipeItem: RecipeItem?,position: Int){
val dialogView = LayoutInflater.from(context).inflate(R.layout.add_recipe_measure_dialog, null)
val dialog = AlertDialog.Builder(context, R.style.RoundedCornersDialog).setView(dialogView).show()
dialog.setCancelable(false)
val displayRectangle = Rect()
val window = activity?.window
window?.decorView?.getWindowVisibleDisplayFrame(displayRectangle)
dialog.window?.setLayout(
(displayRectangle.width() * 0.5f).toInt(),
dialog.window!!.attributes.height
)
context?.resources?.let {
dialogView.findViewById<TextView>(R.id.recipe_measure_title).text = java.lang.String.format(it.getString(R.string.addRecipeMeasure), unitsArray[currentMeasurementUnits - 1])
}
val doneBtn = dialogView.findViewById<ImageButton>(R.id.recipe_measure_done_btn)
val closeBtn = dialogView.findViewById<ImageButton>(R.id.close_btn_add_recipe)
val conversionEditText = dialogView.findViewById<ClearFocusEditText>(R.id.recipe_conversion_tie)
doneBtn.isEnabled = false
if (recipeItem != null ){
conversionEditText.setText("${recipeItem.conversionRatio}")
}
closeBtn.setOnClickListener {
context?.hideKeyboard(it)
dialog.dismiss() }
doneBtn.setOnClickListener {
context?.hideKeyboard(it)
val conversionRatio = conversionEditText.text.toString().toFloat()
if (recipeItem != null){
recipeItem.conversionRatio = conversionRatio
recipeItemList[position] = recipeItem
recipeAdapter.notifyItemChanged(position)
}else{
recipeItemList.add(0,RecipeItem(0,0,conversionRatio,0)) // Use your data class in place of RecipeItem
recipeAdapter.notifyItemInserted(0) // new Item is added to index zero, so adapter has to be updated at index zero
}
// calculating sum
val sum = recipeItemList.map { it.conversionRatio }.sum()
Log.d("tisha==>>","Conversion ratio sum = $sum")
dialog.cancel()
}
}

Get the returned list from firestore based on condition when a value is passed to firestore function

I am trying to return a list from inside firestore function based on if a condition is true.I want to return different lists when different categories are selected.
I tried:
putting the return statement out of firestore function which did not work and returned empty list due to firestore async behaviour.
creating my own callback to wait for Firestore to return the data using interface as I saw in some other questions but in that case how am i supposed to access it as my function has a Int value(i.e.private fun getRandomPeople(num: Int): List<String>)?
What could be the way of returning different lists for different categories based on firestore conditions?
My code(Non Activity class):
class Board// Create new game
(private val context: Context, private val board: GridLayout) {
fun newBoard(size: Int) {
val squares = size * size
val people = getRandomPeople(squares)
createBoard(context, board, size, people)
}
fun createBoard(context: Context, board: GridLayout, size: Int, people: List<String>) {
destroyBoard()
board.columnCount = size
board.rowCount = size
var iterator = 0
for(col in 1..size) {
for (row in 1..size) {
cell = RelativeLayout(context)
val cellSpec = { GridLayout.spec(GridLayout.UNDEFINED, GridLayout.FILL, 1f) }
val params = GridLayout.LayoutParams(cellSpec(), cellSpec())
params.width = 0
cell.layoutParams = params
cell.setBackgroundResource(R.drawable.bordered_rectangle)
cell.gravity = Gravity.CENTER
cell.setPadding(5, 0, 5, 0)
text = TextView(context)
text.text = people[iterator++]
words.add(text.text as String)
text.maxLines = 5
text.setSingleLine(false)
text.gravity = Gravity.CENTER
text.setTextColor(0xFF000000.toInt())
cell.addView(text)
board.addView(cell)
cells.add(GameCell(cell, text, false, row, col) { })
}
}
}
private fun getRandomPeople(num: Int): List<String> {
val mFirestore: FirebaseFirestore=FirebaseFirestore.getInstance()
val mAuth: FirebaseAuth=FirebaseAuth.getInstance()
val currentUser: FirebaseUser=mAuth.currentUser!!
var validIndexes :MutableList<Int>
var chosenIndexes = mutableListOf<Int>()
var randomPeople = mutableListOf<String>()
mFirestore.collection("Names").document(gName).get().addOnSuccessListener(OnSuccessListener<DocumentSnapshot>(){ queryDocumentSnapshot->
var categorySelected:String=""
if (queryDocumentSnapshot.exists()) {
categorySelected= queryDocumentSnapshot.getString("selectedCategory")!!
print("categoryselected is:$categorySelected")
Toast.makeText(context, "Got sel category from gameroom:$categorySelected", Toast.LENGTH_LONG).show()
when(categorySelected){
"CardWords"->{
for (i in 1..num) {
validIndexes=(0..CardWords.squares.lastIndex).toMutableList()
val validIndexIndex = (0..validIndexes.lastIndex).random()
val peopleIndex = validIndexes[validIndexIndex]
chosenIndexes.add(peopleIndex)
val person = CardWords.squares[peopleIndex]
randomPeople.add(person)
validIndexes.remove(peopleIndex)
peopleIndexes = chosenIndexes.toList()
}
}
else->{}
}
}
else {
Toast.makeText(context, "Sel category does not exist", Toast.LENGTH_LONG).show()
}
}).addOnFailureListener(OnFailureListener { e->
val error=e.message
Toast.makeText(context,"Error:"+error, Toast.LENGTH_LONG).show()
})
return randomPeople.toList()
}
}
Activity A:
Board(this, gridLay!!)

If data in a recycler view item is null don't display the view holder

I want to check if data that comes from the server is null or not. If is not null then populate the recycler view item in my case being a CardView and if it is null don't display the CardView at all.
In my recycler view adapter i have this:
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
var firstName = itemsList[position].firstName
var lastName = itemsList[position].lastName
if (firstName.isNullOrEmpty() && lastName.isNullOrEmpty()) {
//...what shoud i write here ?
} else {
holder.name?.text = firstName + " " + lastName
}
}
class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
val name = itemView.name
}

you should do something like this:
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
var firstName = itemsList[position].firstName
var lastName = itemsList[position].lastName
if (firstName.isNullOrEmpty() && lastName.isNullOrEmpty()) {
yourCardView.visibility = View.INVISIBLE //or GONE if you do not want to keep its space
holder.name?.text = ""
} else {
yourCardView.visibility = View.VISIBLE
holder.name?.text = firstName + " " + lastName
}
}
class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
val name = itemView.name
}
but if cardview is your root item and you do not want to show the list item at all,you should change your main list with a code like this in your adapter constructor:
filteredList = itemsList?.filter {
(it.firstname.isNullOrEmpty() || it.lastName.isNullOrEmpty()).not()
}

Even if you change the visibility of the CardView the gap in the RecyclerView will be there.
It's better to remove the empty items from the list, prior to setting the adapter:
list.removeIf { it.firstName.isNullOrEmpty() && it.lastName.isNullOrEmpty() }

android fragment in a listview

I have a listView that has a custom layout that contains a fragment. The problem I am having is when I add the fragment to the listView row I get a never ending loop that keeps going through the getView code.
I have only been doing Android coding for a couple months so any help would be great. Please let me know if there is any more of my code I need to post
This is my adapter code:
class AdapterReply(
private val context: Context,
private val ph: Phan,
private val replies: ArrayList<Reply> ) : BaseAdapter() {
override fun getCount(): Int {
return replies.size
}
override fun getItem(position: Int): Reply {
return replies[position]
}
override fun getItemId(position: Int): Long {
return position.toLong()
}
override fun getView(position: Int, convertView: View?, viewGroup: ViewGroup?): View? {
val rowMain: View?
val rowHolder: ListRowHolder
val contacts = ph.contacts
val reply = replies[position]
Log.d("AdapterReply", "Binding reply: Position $position ${reply.id} Detail: ${reply.detail}")
if (convertView == null) {
val layoutInflater = LayoutInflater.from(viewGroup!!.context)
rowMain = layoutInflater.inflate(R.layout.reply_item_row, viewGroup, false)
rowHolder = ListRowHolder(rowMain)
rowMain.tag = rowHolder
Log.d("AdapterReply", "New Item")
} else {
rowMain = convertView
rowHolder = rowMain.tag as ListRowHolder
Log.d("AdapterReply", "Old item from memory")
}
rowHolder.itemDetail.text = Helpers.anonymizeContent(reply.detail, ph.anonymousMetadata, ph.isViewerMember())
rowHolder.itemLastActive.text = Helpers.getFormattedDate(reply.lastActive())
if(reply.attachments.size > 0){
val imageAttachment = reply.attachments.filter { attachment: Attachment -> attachment.type == 0 }[0]
var imageUrl = Constants.BASE_URL + imageAttachment.url
if(imageAttachment.anonymous()){
imageUrl = Constants.BASE_URL + imageAttachment.anonUrl
}
Picasso.with(rowMain!!.context).load(imageUrl).into(rowHolder.itemImage)
}
var poster: Contact? = reply.contact
if(contacts.size > 0) {
val posterList = contacts.filter { contact: Contact -> contact.id == reply.rlContactID }
if (posterList.isNotEmpty()) {
poster = posterList[0]
}
}
if(poster != null) {
if(poster.anonymizedName.isNotEmpty()) {
rowHolder.itemPoster.text = poster.anonymizedName
} else {
val posterName = "${poster.firstName} ${poster.lastName}"
rowHolder.itemPoster.text = posterName
}
//Code the causes the problem
val manager = (rowMain!!.context as AppCompatActivity).supportFragmentManager
val posterAvatarFragment =
AvatarFragment.newInstance(poster)
manager.beginTransaction()
.add(R.id.reply_avatar_fragment, posterAvatarFragment, "ReplyAvatarFragment")
.commit()
//End Code the causes the problem
}
bindReplies(rowMain, ph, reply.replies)
return rowMain
}
internal class ListRowHolder(row: View?) {
var itemDetail : TextView = row!!.reply_view_detail
var itemImage : ImageView = row!!.reply_view_image
var itemPoster : TextView = row!!.reply_view_posterName
var itemLastActive : TextView= row!!.reply_view_lastActive
var itemReplyReplies: ListView = row!!.reply_view_replyList
}
private fun bindReplies(viewRow: View?, ph: Phan, replies : ArrayList<Reply>){
if(replies.isNotEmpty()) {
val myObject = AdapterReply(context, ph, replies)
val replyListView = viewRow!!.reply_view_replyList
Log.d("AdapterReply", "Binding Replies: ${ph.encodedId} ${replies.size}")
replyListView.adapter = myObject
}
}
}

manager.beginTransaction()
.add(R.id.reply_avatar_fragment, posterAvatarFragment, "ReplyAvatarFragment")
.commit()
Man, I'm not sure do you know, what function performs adapter class in listview. Adapter class is used to fill listview by rows passed in array inside class constructor. getView method is called for every row in array, so for example, if you have an array with 10 rows, this code will fire ten times. If you do automatically change fragment to another, and during filling an old view you will change layout to a another layout with the same data, your code will make an infinity loop, because you will repeat all time the same cases. You should avoid actions, which will dynamically change layout during load him. In my sugestion, if you want to use a multiple layouts inside one adapter, there are two special methods to set layout for row, based on some conditions: getItemViewType and getViewTypeCount. In first one you can use your conditions to check, which layout should be used for row. Second one is to set number of layouts, which will be used in your adapter class. Let search some examples of usage.

How to pick every time new or unique random item from a array list in android?

I need to pick a new item from a list that hasn't been picked already until there are no more.
Here is my code:
private var quizQuestionList: ArrayList<Quiz>
private var pickedItems: ArrayList<Int>
private var random: Random = Random()
private fun pickItem(): Quiz {
var index = random?.nextInt(quizQuestionList!!.size)
if (pickedItems.contains(index)) {
index = random?.nextInt(quizQuestionList!!.size)
pickedItems.add(index)
} else {
pickedItems.add(index)
}
val item = quizQuestionList!!.get(index!!)
return item
}
Please suggest any solution that gives me a new item every time. I used an int list for all previously picked items and check every time when picked new item but I didn't get success.

It isn't obvious what you are looking for, but it looks like you want to show different Quiz question from ArrayList. In condition of, when that question is shown, no more same question will be shown. Here is how you should do, I will give you just the logic you could try it yourself:
import java.util.Random
fun main(args: Array<String>) {
val random = Random()
var randomInt: Int
var pickedInt: MutableSet<Int> = mutableSetOf()
fun rand(from: Int, to: Int): Int{
do{
randomInt = random.nextInt(to - from) + from
}while(pickedInt.contains(randomInt))
pickedInt.add(randomInt)
return randomInt
}
while(pickedInt.size < 9){
var differentNumber = rand(1,11)
println(differentNumber)
}
}
This will print nine different Number. The way I choosing MutableSet is because it will only have unique values, no duplicated value. Hope it helps!

here is code for same::
val arrayList = ArrayList<String>()
arrayList.add("a")
arrayList.add("b")
arrayList.add("c")
arrayList.add("d")
arrayList.add("e")
arrayList.add("f")
arrayList.add("g")
arrayList.add("h")
arrayList.add("i")
arrayList.add("j")
arrayList.add("k")
random = Random()
Low = 0
High = arrayList.size
val generateRandom = findViewById<View>(R.id.generateRandom) as Button
generateRandom.setOnClickListener {
val Result = random.nextInt(High - Low) + Low
Log.v("check", arrayList[Result])
}
Please let me know if need more!!

Try this way
class MainActivity : AppCompatActivity() {
private var arrayList = ArrayList<String>()
private var lastItem = -1
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
for (i in 0..9) {
arrayList.add(i.toString())
}
btnData.setOnClickListener {
Log.e("RANDOM_NUMBER", "" + getRandomItemFromList())
}
}
private fun getRandomItemFromList(): Int {
val randomValue = Random().nextInt(arrayList.size)
return if (randomValue != lastItem) {
lastItem = randomValue
randomValue
} else {
getRandomItemFromList()
}
}
}

I made this extension for the ArrayList class in Kotlin you can use it multiple times in only one line.
fun <T> ArrayList<T>.generateRandomItems(numberOfItems: Int): ArrayList<T> {
val range = if(numberOfItems > this.size){this.size}else{numberOfItems}
val randomItems = ArrayList<T>()
for (i in 0..range) {
var randomItem: T
do {
randomItem = this.random()
} while (randomItems.contains(randomItem))
randomItems.add(randomItem)
}
return randomItems
}
Usage:
val randomUsersList = usersList.generateRandomItems(20)
Note: the usersList is the list that has items to generate random items from.