Peace
i have made simple recyclerview, with interface clickListener
consisting of 4 items showing toast on click.
It works fine if i single click per second,
but if i Rapidly click on different items ( 2 or 3 times in 1 seconds )
it still shows the toast each second,
not rapidly changing the toast
data class code:
package com.elsersy.rv5
data class Items (var textt:String) {
}
adapter code
package com.elsersy.rv5
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.recyclerview.widget.DiffUtil
import androidx.recyclerview.widget.RecyclerView
class MyAdapter(private var stringList:ArrayList<Items>,private val listener:MyOnClickListener):
RecyclerView.Adapter<MyAdapter.MyViewHolder>() {
inner class MyViewHolder(itemView:View):RecyclerView.ViewHolder(itemView) {
var text:TextView = itemView.findViewById(R.id.textView)
init {
itemView.setOnClickListener {
val position = absoluteAdapterPosition
if (position != RecyclerView.NO_POSITION)
{
listener.onItemClick(position)
}
}
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val itemView = LayoutInflater.from(parent.context).inflate(R.layout.row_item,parent,false)
return MyViewHolder(itemView)
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
val currentItem = stringList[position]
holder.text.text = currentItem.textt
}
override fun getItemCount(): Int {
return stringList.size
}
interface MyOnClickListener{
fun onItemClick(position: Int)
}
fun setData(newItemList:ArrayList<Items>){
val diffUtil = MyDiffUtil(stringList,newItemList)
val diffResults = DiffUtil.calculateDiff(diffUtil)
stringList = newItemList
diffResults.dispatchUpdatesTo(this)
}
}
ActivityMainCode
package com.elsersy.rv5
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import androidx.recyclerview.widget.LinearLayoutManager
import com.elsersy.rv5.databinding.ActivityMainBinding
class MainActivity : AppCompatActivity(),MyAdapter.MyOnClickListener {
private lateinit var binding: ActivityMainBinding
private lateinit var stringList:ArrayList<Items>
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
binding.recyclerView.layoutManager = LinearLayoutManager(this)
stringList = arrayListOf<Items>()
getStrings()
binding.recyclerView.adapter=MyAdapter(stringList,this)
}
private fun getStrings() {
for (a in 0..4){
var string_Array = resources.getStringArray(R.array.string_array)
stringList.add(Items(string_Array[a]))
}
}
override fun onItemClick(position: Int) {
Toast.makeText(this,"$position is clicked", Toast.LENGTH_SHORT).show()
}
}
If you want to cancel the previous toast before showing a new one, assign it as a member variable and cancel it before showing the new one:
private var toast : Toast? = null
..
override fun onItemClick(position: Int) {
toast?.cancel()
toast = Toast.makeText(this,"$position is clicked", Toast.LENGTH_SHORT)
toast?.show()
}
Related
I am trying to make a game of life grid based game in Android Studio using kotlin. Essentially, every second the grid will update based off a set of rules. However, I can not for the life of me get the grid to update.
For some reason, notifyItemChanged() is not calling onBindViewHolder to properly update the grid visually. I was able to find a work around for some cases, that being calling onBindViewHolder specifically and passing through the current cellViewHolder and it's position, but this won't get me the result I am looking for. Specifically, in the function I declared testUpdate(), I need to be able to change an array of data that the grid is based on, and then from that function notify the grid that changes were made and it should update. However, notifyItemChanged() as well as notifyDatasetChanged() both do not call onBindViewHolder(). I am at a loss, any help would be much appreciated!
I am very new to Kotlin, so I apologize if this code is horrible.
Here is my code:
package com.example.project2
import android.graphics.Color
import android.os.Bundle
import android.text.Layout
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import android.widget.ImageButton
import android.widget.TextView
import androidx.fragment.app.Fragment
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.RecyclerView
import android.os.Handler;
class BoardFragment : Fragment() {
private lateinit var recyclerView: RecyclerView
var gridArray = IntArray(400)
val handler = Handler()
var isRunning: Boolean = false
val colorRed = Color.RED
val colorBlue = Color.BLUE
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val view = inflater.inflate(R.layout.board_fragment, container, false)
val startButton = view.findViewById(R.id.start_button) as Button
val recyclerView = view.findViewById(R.id.recycler_view) as RecyclerView
recyclerView.layoutManager = GridLayoutManager(activity, 20)
recyclerView.adapter = GridAdapter()
startButton.setOnClickListener {
isRunning = !isRunning
if (isRunning) {
testUpdate()
}
}
return view
}
fun testUpdate() {
handler.postDelayed({
if (gridArray[3] == 0) {
gridArray[3] = 1
} else {
gridArray[3] = 0
}
if (isRunning) {
testUpdate()
}
GridAdapter().notifyItemChanged(3)
}, 1000)
}
override fun onStart() {
super.onStart()
}
private inner class CellViewHolder(cellView: View): RecyclerView.ViewHolder(cellView) {
val button: ImageButton
init {
button = cellView.findViewById(R.id.cell_button)
button.setColorFilter(null)
button.setOnClickListener {
if (gridArray[position] == 0) {
gridArray[position] = 1
} else {
gridArray[position] = 0
}
GridAdapter().notifyItemChanged(position)
GridAdapter().onBindViewHolder(this, position)
}
}
fun display(position: Int) {
}
}
private inner class GridAdapter: RecyclerView.Adapter<CellViewHolder>() {
final val NUM_CELLS: Int = 400
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CellViewHolder {
val inflater: LayoutInflater = LayoutInflater.from(parent.context)
val cellView: View = inflater.inflate(R.layout.board_cell, parent, false)
return CellViewHolder(cellView)
}
override fun onBindViewHolder(holder: CellViewHolder, position: Int) {
holder.display(position)
if (gridArray[position] == 0) {
holder.button.setColorFilter(null)
} else {
holder.button.setColorFilter(Color.RED)
}
}
override fun getItemCount(): Int {
return NUM_CELLS
}
}
}
I don't know what you're trying to achieve but a few tip
notifyItemChange() should be called from the Adapter class.
You're creating a new instances of GridAdapter GridAdapter().notifyItemChanged(position)
change
GridAdapter().notifyItemChanged(position)
to
recyclerView.adapter.notifyItemChanged(position)
modify your class like this
package com.example.project2
import android.graphics.Color
import android.os.Bundle
import android.text.Layout
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import android.widget.ImageButton
import android.widget.TextView
import androidx.fragment.app.Fragment
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.RecyclerView
import android.os.Handler;
class BoardFragment : Fragment() {
private lateinit var recyclerView: RecyclerView
var gridArray = IntArray(400)
val handler = Handler()
var isRunning: Boolean = false
val colorRed = Color.RED
val colorBlue = Color.BLUE
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val view = inflater.inflate(R.layout.board_fragment, container, false)
val startButton = view.findViewById(R.id.start_button) as Button
val recyclerView = view.findViewById(R.id.recycler_view) as RecyclerView
recyclerView.layoutManager = GridLayoutManager(activity, 20)
recyclerView.adapter = GridAdapter()
startButton.setOnClickListener {
isRunning = !isRunning
if (isRunning) {
testUpdate()
}
}
return view
}
fun testUpdate() {
handler.postDelayed({
if (gridArray[3] == 0) {
gridArray[3] = 1
} else {
gridArray[3] = 0
}
if (isRunning) {
testUpdate()
}
recyclerView.adapter.notifyItemChanged(3)
}, 1000)
}
override fun onStart() {
super.onStart()
}
private inner class CellViewHolder(cellView: View): RecyclerView.ViewHolder(cellView) {
val button: ImageButton
init {
button = cellView.findViewById(R.id.cell_button)
button.setColorFilter(null)
button.setOnClickListener {
if (gridArray[position] == 0) {
gridArray[position] = 1
} else {
gridArray[position] = 0
}
}
}
fun display(position: Int) {
}
}
private inner class GridAdapter: RecyclerView.Adapter<CellViewHolder>() {
final val NUM_CELLS: Int = 400
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CellViewHolder {
val inflater: LayoutInflater = LayoutInflater.from(parent.context)
val cellView: View = inflater.inflate(R.layout.board_cell, parent, false)
return CellViewHolder(cellView)
}
override fun onBindViewHolder(holder: CellViewHolder, position: Int) {
if (gridArray[position] == 0) {
holder.button.setColorFilter(null)
} else {
holder.button.setColorFilter(Color.RED)
}
holder.display(position)
recyclerView.adapter.notifyItemChanged(3)
}
override fun getItemCount(): Int {
return NUM_CELLS
}
}
}
There was a problem with the recyclerview list being added only initially and not being added after the second.
MainActivity.kt
package com.malkinfo.editingrecyclerview
import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.google.android.material.floatingactionbutton.FloatingActionButton
import com.malkinfo.editingrecyclerview.added_data.Companion.start_time_hou
import com.malkinfo.editingrecyclerview.added_data.Companion.start_time_min
import com.malkinfo.editingrecyclerview.model.UserData
import com.malkinfo.editingrecyclerview.view.UserAdapter
class MainActivity : AppCompatActivity() {
private lateinit var addsBtn:FloatingActionButton
private lateinit var recv:RecyclerView
private lateinit var userList:ArrayList<UserData>
private lateinit var userAdapter:UserAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
userList = ArrayList()
addsBtn = findViewById(R.id.addingBtn)
recv = findViewById(R.id.mRecycler)
userAdapter = UserAdapter(this,userList)
recv.layoutManager = LinearLayoutManager(this)
recv.adapter = userAdapter
addsBtn.setOnClickListener {
startActivity(Intent(this#MainActivity,next_activity::class.java))
}
if(intent.hasExtra("name")){
addInfo2()
}
}
private fun addInfo2(): ArrayList<UserData> {
var names = start_time_hou
var number = start_time_min
userList.add(UserData("Name: ${names}","Mobile No. : $number"))
userAdapter.notifyDataSetChanged()
Toast.makeText(this,"${userList}",Toast.LENGTH_LONG).show()
return userList
}
}
UserAdapter.kt
package com.malkinfo.editingrecyclerview.view
import android.content.Context
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.*
import androidx.recyclerview.widget.RecyclerView
import com.malkinfo.editingrecyclerview.R
import com.malkinfo.editingrecyclerview.model.UserData
class UserAdapter(val c:Context,val userList:ArrayList<UserData>):RecyclerView.Adapter<UserAdapter.UserViewHolder>()
{
inner class UserViewHolder(val v:View):RecyclerView.ViewHolder(v){
var name:TextView
var mbNum:TextView
var mMenus:ImageView
var mToggle:ToggleButton
init {
name = v.findViewById<TextView>(R.id.mTitle)
mbNum = v.findViewById<TextView>(R.id.mSubTitle)
mToggle=v.findViewById(R.id.toggleButton)
mMenus = v.findViewById(R.id.mMenus)
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): UserViewHolder {
val inflater = LayoutInflater.from(parent.context)
val v = inflater.inflate(R.layout.list_item,parent,false)
return UserViewHolder(v)
}
override fun onBindViewHolder(holder: UserViewHolder, position: Int) {
val newList = userList[position]
holder.name.text = newList.userName
holder.mbNum.text = newList.userMb
}
override fun getItemCount(): Int {
return userList.size
}
}
next_activity.kt
package com.malkinfo.editingrecyclerview
import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import com.malkinfo.editingrecyclerview.added_data.Companion.end_time_hou
import com.malkinfo.editingrecyclerview.added_data.Companion.end_time_min
import com.malkinfo.editingrecyclerview.added_data.Companion.start_time_hou
import com.malkinfo.editingrecyclerview.added_data.Companion.start_time_min
import kotlinx.android.synthetic.main.activity_next2.*
import kotlinx.android.synthetic.main.add_item.*
class next_activity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_next2)
button2.setOnClickListener {
finish()
}
button.setOnClickListener {
start_time_hou="1"
start_time_min="2"
end_time_hou=3
end_time_min=4
val intent_time= Intent(this#next_activity,MainActivity::class.java)
intent_time.putExtra("name","lir")
startActivity(intent_time)
}
button3.setOnClickListener {
start_time_hou="1123"
start_time_min="52"
val intent_time= Intent(this#next_activity,MainActivity::class.java)
intent_time.putExtra("name","lir")
startActivity(intent_time)
}
}
}
added_data.kt
package com.malkinfo.editingrecyclerview
class added_data {
companion object {
var start_time_hou = "0"
var start_time_min = "0"
var end_time_hou = 0
var end_time_min = 0
}
}
UserData.kt
package com.malkinfo.editingrecyclerview.model
data class UserData (
var userName:String,
var userMb:String
)
What I want is to move from MainACtivity to next_activity, and every time I press the button in next_activity, a new recycleview element is created. However, as I said earlier, there is no additional generation and only one element of data changes.
The issue here is, you are adding items to your userList in MainActivity but you are not passing them to the recyclerview. That is why userAdapter.notifyDataSetChanged() is not causing any effect.
Try this and let me know if there is still some issue :)
In MainActivity
class MainActivity : AppCompatActivity() {
private lateinit var addsBtn:FloatingActionButton
private lateinit var recv:RecyclerView
private lateinit var userList:ArrayList<UserData>
private lateinit var userAdapter:UserAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
userList = ArrayList()
addsBtn = findViewById(R.id.addingBtn)
recv = findViewById(R.id.mRecycler)
userAdapter = UserAdapter(this)
userAdapter.setData(userList)
recv.layoutManager = LinearLayoutManager(this)
recv.adapter = userAdapter
addsBtn.setOnClickListener {
startActivity(Intent(this#MainActivity,next_activity::class.java))
}
if(intent.hasExtra("name")){
addInfo2()
}
}
private fun addInfo2(): ArrayList<UserData> {
var names = start_time_hou
var number = start_time_min
userList.add(UserData("Name: ${names}","Mobile No. : $number"))
userAdapter.setData(userList)
Toast.makeText(this,"${userList}",Toast.LENGTH_LONG).show()
return userList
}
}
UserAdapter
class UserAdapter(val c:Context):RecyclerView.Adapter<UserAdapter.UserViewHolder>()
{
private var _userList: ArrayList<UserData>? = null
inner class UserViewHolder(val v:View):RecyclerView.ViewHolder(v){
var name:TextView
var mbNum:TextView
var mMenus:ImageView
var mToggle:ToggleButton
init {
name = v.findViewById<TextView>(R.id.mTitle)
mbNum = v.findViewById<TextView>(R.id.mSubTitle)
mToggle=v.findViewById(R.id.toggleButton)
mMenus = v.findViewById(R.id.mMenus)
}
}
fun setData(userList: ArrayList<UserData>) {
_userList = userList
notifyDataSetChanged()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int):
UserViewHolder {
val inflater = LayoutInflater.from(parent.context)
val v = inflater.inflate(R.layout.list_item,parent,false)
return UserViewHolder(v)
}
override fun onBindViewHolder(holder: UserViewHolder, position: Int) {
val newList = _userList?.get(position)
holder.name.text = newList?.userName
holder.mbNum.text = newList?.userMb
}
override fun getItemCount(): Int {
if(_userList == null)
return 0
else
return _userList!!.size
}
}
I get error when I press button inside recycler view. My application is not crashing. I am trying to set a button in the recycler view and callingsetOnClickListener inside onBindViewHolder. Inside the holder.Button.setOnClickListener{}I change the button text to notified. But when I press a button the values of other button text in another list also changes. This is a listview of firestore documents. I have many documents that are uploaded into the recycler view. If I am getting the error how should I implement the button onclicklistener without this error.[![https://i.stack.imgur.com/S0Oxm.jpg][1]][1] [![enter image description here][2]][2]
/**This my activity for recycler view*/
package com.example.bloodbankcompany.recyclerview
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import android.widget.Adapter
import android.widget.Toast
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.example.bloodbankcompany.MyAdapter
import com.example.bloodbankcompany.R
import com.example.bloodbankcompany.User1
import com.example.bloodbankcompany.User2
import com.google.firebase.firestore.*
import java.lang.NullPointerException
class MainActivity2 : AppCompatActivity() {
private lateinit var recyclerView: RecyclerView
private lateinit var userArrayList: ArrayList<User2>
private lateinit var myAdapter: MyAdapter2
private val mFireStore = FirebaseFirestore.getInstance()
var db = FirebaseFirestore.getInstance()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main2)
recyclerView= findViewById(R.id.recyclerview)
recyclerView.layoutManager = LinearLayoutManager(this)
recyclerView.setHasFixedSize(true)
userArrayList= arrayListOf()
myAdapter =MyAdapter2(userArrayList)
recyclerView.adapter = myAdapter
EventChangeListener()
}
private fun EventChangeListener() {
try {
mFireStore.collection("applicationForm").addSnapshotListener(object :
EventListener<QuerySnapshot> {
override fun onEvent(value: QuerySnapshot?, error: FirebaseFirestoreException?) {
if (error != null) {
Log.e("firestore error", error.message.toString())
}
try {
for (dc: DocumentChange in value?.documentChanges!!) {
if (dc.type == DocumentChange.Type.ADDED) {
userArrayList.add(dc.document.toObject(User2::class.java))
}
// Toast.makeText(applicationContext,userArrayList.toString(), Toast.LENGTH_SHORT).show()
}
} catch (e:NullPointerException){
}
myAdapter.notifyDataSetChanged()
}
})
} catch (e:NullPointerException){
}
}
}
/**
* This is my myAdapter activity for adapater*/
package com.example.bloodbankcompany.recyclerview
import android.content.Intent
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import android.widget.TextView
import android.widget.Toast
import androidx.recyclerview.widget.RecyclerView
import com.example.bloodbankcompany.R
import com.example.bloodbankcompany.RegisterActivity
import com.example.bloodbankcompany.User2
import com.google.firebase.firestore.FirebaseFirestore
import kotlinx.android.synthetic.main.list_item2.view.*
class MyAdapter2(private val userList: ArrayList<User2>): RecyclerView.Adapter<MyAdapter2.MyViewHolder>(){
var id: String = ""
private val mFireStore = FirebaseFirestore.getInstance()
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyAdapter2.MyViewHolder {
val itemView = LayoutInflater.from(parent.context).inflate(R.layout.list_item2,parent,false)
return MyViewHolder(itemView)
}
override fun onBindViewHolder(holder: MyAdapter2.MyViewHolder, position: Int) {
val user:User2 = userList[position]
holder.name.text= user.name
holder.phone.text= user.phone
holder.address.text =user.address
holder.bloodGroup.text= user.bloodgroup
holder.id.text = user.id
//Setting onclicklistener to my adapter and starting intent
holder.button.setOnClickListener {
// holder.io = "kkj"
// holder.id.text = " "
holder.button.setText("notified")
// val context=holder.button.context
// val intent = Intent( context, RegisterActivity::class.java)
// context.startActivity(intent)
}
}
override fun getItemCount(): Int {
return userList.size
}
public class MyViewHolder(itemView : View): RecyclerView.ViewHolder(itemView){
val name : TextView = itemView.findViewById(R.id.tvfirstname1)
val phone :TextView= itemView.findViewById(R.id.tvphone11)
val address : TextView= itemView.findViewById(R.id.tvaddress1)
val bloodGroup: TextView =itemView.findViewById(R.id.tvbloodg1)
val id: TextView = itemView.findViewById(R.id.tvid)
var io: String? = ""
var button: Button = itemView.findViewById(R.id.btn_notify)
class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView){
init {
itemView.btn_notify.setOnClickListener {
}
}
}
}
} ```
[1]: https://i.stack.imgur.com/S0Oxm.jpg
[2]: https://i.stack.imgur.com/BqDMf.jpg
create interface for clickListener in your adapter and set it in constructor
interface OnItemClickListener {
fun onItemClick(position: Int)
}
and in ViewHolder set bind your button
fun bind(position: Int, listener: OnItemClickListener) {
button.setOnClickListener { v -> listener.onItemClick(position) }
}
and then set this code in onBindViewHolder
holder.bind( position , onItemClickListener)
finally when click on button you can action in Activity or Fragment
example :
adapter = Adapter(getContext(), models) { position -> }
Simple Code, Without using Interface
Actually what I found is you were doing it the correct way, but you were using two ViewHolder classes there which is the cause of issue. Try to use the below code once and try again. Hope it works.
class mAdapter(val context: Context, private val dataList: ArrayList<String>):
RecyclerView.Adapter<mAdapter.ViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): mAdapter.ViewHolder {
val v = LayoutInflater.from(parent.context).inflate(R.layout.item_card_view, parent, false)
return mAdapter.ViewHolder(v)
}
override fun onBindViewHolder(holder: mAdapter.ViewHolder, position: Int) {
holder.txtView.setText(dataList.get(position))
//Your Button setOnClickLister
holder.btnName.setOnClickListener {
// action here
}
}
override fun getItemCount(): Int {
return dataList.size
}
class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
val txtView = itemView.findViewById(R.id.textView) as TextView
val btnName = itemView.findViewById(R.id.btnName) as Button
}
}
I have a RecyclerView and I have to pass data to another activity when u click on an item. When someone clicks on the first item I need to pass the data of that item to an activity.
This is the part of the fragment where the recycler view is located:
class TrafficFragment : Fragment() {
private lateinit var trafficViewModel: TrafficViewModel
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
trafficViewModel =
ViewModelProviders.of(this).get(TrafficViewModel::class.java)
val root = inflater.inflate(R.layout.fragment_traffic, container, false)
//...
val recyclerViewTraffic: RecyclerView = root.findViewById(R.id.recyclerViewTraffic)
recyclerViewTraffic.apply {
layoutManager = LinearLayoutManager (this#TrafficFragment.context)
Log.d("DEBUG", MainActivity.clickArray.toString())
adapter = TrafficAdapter(MainActivity.clickArray){
var intent = Intent(activity, ClickDetail::class.java)
startActivity(intent)
}
}
return root
}
}
The adapter:
package com.example.example
import android.content.Intent
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.recyclerview.widget.RecyclerView
import kotlinx.android.synthetic.main.traffic_recycler_layout.view.*
class TrafficAdapter(private val trafficClick: List<TrafficClick>, val clickDetail: () -> Unit) :
RecyclerView.Adapter<TrafficAdapter.ViewHolder>(){
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val layoutView = LayoutInflater.from(parent.context).inflate(R.layout.traffic_recycler_layout, parent, false)
return ViewHolder(layoutView)
}
override fun getItemCount(): Int = MainActivity.clicksNumber
companion object{
var idClick: String?= String()
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val clicks = trafficClick[position]
holder.view.indirizzoIp.text = "${clicks.ip}"
holder.view.isp.text= "${clicks.organization}"
holder.view.data.text = "${clicks.data_creation}"
holder.view.numberText.text = "${clicks.id_campaign}"
holder.view.setOnClickListener {
clickDetail.invoke()
}
}
class ViewHolder(val view: View) : RecyclerView.ViewHolder(view)
}
and this is the activity that I need to open when I click on the item with the details of that item:
package com.example.example
import android.os.Bundle
import android.util.Log
import android.view.View
import androidx.appcompat.app.AppCompatActivity
import kotlinx.android.synthetic.main.traffic_click_detail.*
class ClickDetail : AppCompatActivity(){
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.traffic_click_detail)
}
}
var intent = Intent(activity, ClickDetail::class.java)
intent.putExtra("your_key",MainActivity.clickArray.toString())
startActivity(intent)
class ClickDetail : AppCompatActivity(){
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.traffic_click_detail)
val YourData = getIntent().getStringExtra("your_key")
}
}
If I suppose you want to pass and id, replace this
holder.view.setOnClickListener {
clickDetail.invoke()
}
by
holder.view.setOnClickListener {
ClickDetail.launch(holder.itemView.context, /*your ID*/)
}
Then to retrieve your data
class ClickDetail : AppCompatActivity(){
companion object {
private const val EXTRA_KEY_ID = "CLICKDETAIL.EXTRA_KEY_ID"
fun launch(launcher: Activity, id: Int) {
val intent = Intent(launcher, ClickDetail::class.java)
.apply {
putExtra(EXTRA_KEY_ID, id)
}
launcher.startActivity(intent)
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.traffic_click_detail)
val id = intent.getIntExtra("EXTRA_KEY_ID")
}
}
I want to create a new intent/activity when the user clicks on a cardview respectively and i was wondering how does one do it in kotlin. i noticed most tutorials are in java and i'm a student who did not learn java.
package com.example.ttshfypj.adapters
import androidx.fragment.app.Fragment
import android.view.View
import android.view.LayoutInflater
import android.view.ViewGroup
import androidx.recyclerview.widget.RecyclerView
import com.example.ttshfypj.data_class.medications
import android.widget.ImageView
import android.widget.TextView
import com.example.ttshfypj.R
import com.squareup.picasso.Picasso
import kotlinx.android.synthetic.main.list_medication.view.*
class medicationAdapter (val medicationlist: ArrayList<medications>) : RecyclerView.Adapter<medicationAdapter.ViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val v = LayoutInflater.from(parent.context).inflate(R.layout.list_medication, parent, false)
return ViewHolder(v)
}
override fun getItemCount(): Int {
return medicationlist.size
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val medicationgroup: medications = medicationlist[position]
holder?.medicationnamevar?.text = medicationgroup.medicineN
holder?.medicationschedulevar?.text = medicationgroup.MedicineTime
val imagemedicine = holder?.itemView?.medicationimageview
Picasso.get().load(medicationgroup.MedicineImage).into(imagemedicine)
}
class ViewHolder(itemView: View) :RecyclerView.ViewHolder(itemView) {
val medicationnamevar = itemView.findViewById(R.id.medicationname) as TextView
val medicationschedulevar = itemView.findViewById(R.id.medicationschedule) as TextView
}
}
If you are using kotlin you can also use method reference where you directly pass a method to be called inside the adapter and you can directly invoke it there.
Activity.kt
Adapter(this::itemClickHandler);
private fun itemClickHandler(int position){
// your logic here
}
Adapter.kt
class Adapater(val itemClickHandler:(Int)->Unit):RecyclerView.Adapter(){
override fun onBindViewHolder(){
//you can invoke it here like this
itemClickHandler.invoke(adapterPosition);
}
}
please refer this full code
MainActivity.kt
package com.example.myapplication
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import androidx.recyclerview.widget.LinearLayoutManager
import kotlinx.android.synthetic.main.activity_main.*
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val list = mutableListOf<Items>()
for(i in 1..25){
list.add(Items(CHILD,"Child"))
}
with(rvList) {
layoutManager = LinearLayoutManager(this#MainActivity)
adapter = Adapter(list, this#MainActivity::onItemClickHandler)
}
}
private fun onItemClickHandler(position:Int){
Log.d("***","${position}");
//here you can start a new intent to open a new activity on click of item
}
}
The adapter code is as following
package com.example.myapplication
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.recyclerview.widget.RecyclerView
import kotlinx.android.synthetic.main.layout_child.view.*
import kotlinx.android.synthetic.main.layout_header.view.*
const val HEADER = 1;
const val CHILD = 2;
data class Items(val type: Int, val text: String)
class Adapter(private val list: List<Items>, val itemClickHandler: (Int) -> Unit) :
RecyclerView.Adapter<Adapter.HeaderViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): HeaderViewHolder {
val headerView =
LayoutInflater.from(parent.context).inflate(R.layout.layout_header, parent, false)
val headerViewHolder = HeaderViewHolder(headerView)
headerView.setOnClickListener {
itemClickHandler.invoke(headerViewHolder.adapterPosition)
}
return headerViewHolder
}
override fun getItemCount(): Int = list.size
override fun onBindViewHolder(holder: HeaderViewHolder, position: Int) {
holder.onBind(list[position].text)
}
inner class HeaderViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
fun onBind(text: String) {
itemView.tvHeader.text = text
}
}
}
Hope this helps and you are able to follow
You can create an interface for Item Click Listener like
interface MyItemClickListener{
fun itemClick(position: Int)
}
Now you should pass context to the constructor of your adapter.
class medicationAdapter (val medicationlist: ArrayList<medications>, var context: Context) : RecyclerView.Adapter<medicationAdapter.ViewHolder>() {...}
and create an instance of MyItemClickListener inside your adapter
// create instance of MyItemClickListener
private val clickListener = context as MyItemClickListener
And setclick listener on your view inside the onCreateViewHolder.
modify your adapter like this
class medicationAdapter (val medicationlist: ArrayList<medications>, var context: Context) : RecyclerView.Adapter<medicationAdapter.ViewHolder>() {
// create instance of MyItemClickListener
private val clickListener = context as MyItemClickListener
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
var inflater = LayoutInflater.from(parent.context)
var v = inflater.inflate(R.layout.list_medication, parent, false)
var viewHolder = ViewHolder(v)
// here you set click listener on your item view.
v.setOnClickListener {
clickListener.itemClick(viewHolder.adapterPosition)
}
return viewHolder
}
override fun getItemCount(): Int {
return medicationlist.size
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val medicationgroup: medications = medicationlist[position]
holder?.medicationnamevar?.text = medicationgroup.medicineN
holder?.medicationschedulevar?.text = medicationgroup.MedicineTime
val imagemedicine = holder?.itemView?.medicationimageview
Picasso.get().load(medicationgroup.MedicineImage).into(imagemedicine)
}
class ViewHolder(itemView: View) :RecyclerView.ViewHolder(itemView) {
val medicationnamevar = itemView.findViewById(R.id.medicationname) as TextView
val medicationschedulevar = itemView.findViewById(R.id.medicationschedule) as TextView
}
}
And finally, in your activity, you have to implement the MyItemClickListener interface and override the itemClick() like this
class YourActivity: AppCompatActivity(), MyItemClickListener {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// ....
}
override fun itemClick(position: Int) {
Log.d("TAG","Click Item Position: "+position)
// here you can call your new activity according to your item position.
}
}