Develop Reference

onBindViewHolder repeats the results [duplicate]

Here's the XML for my items inside the RecyclerView
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="#+id/cvItems"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_margin="2dp"
card_view:cardElevation="0dp"
card_view:contentPadding="0dp"
card_view:cardBackgroundColor="#FFFFFF"
>
<LinearLayout
android:orientation="horizontal"
android:layout_height="fill_parent"
android:layout_width="fill_parent">
<TextView
android:layout_width="0dip"
android:layout_height="match_parent"
android:layout_weight="0.8"
android:id="#+id/tvContent"
android:textSize="15dp"
android:paddingLeft="5dp"
android:paddingRight="5dp" />
<CheckBox
android:id="#+id/cbSelect"
android:layout_width="0dip"
android:layout_weight="0.2"
android:layout_height="match_parent"
android:button="#drawable/cb_checked"
android:gravity="center_horizontal"
android:textAlignment="center"
android:layout_gravity="center_horizontal" />
</LinearLayout>
</android.support.v7.widget.CardView>
And here's the RecyclerView adapter that inflate the layout above for each of its items:
public class AdapterTrashIncome extends RecyclerView.Adapter<AdapterTrashIncome.ViewHolder> {
private ArrayList<ObjectIncome> myItems = new ArrayList<>();
public AdapterTrashIncome(ArrayList<ObjectIncome> getItems, Context context){
try {
mContext = context;
myItems = getItems;
}catch (Exception e){
Log.e(FILE_NAME, "51: " + e.toString());
e.printStackTrace();
}
}
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView tvContent;
public CheckBox cbSelect;
public ViewHolder(View v) {
super(v);
tvContent = (TextView) v.findViewById(R.id.tvContent);
cbSelect = (CheckBox) v.findViewById(R.id.cbSelect);
}
}
#Override
public void onBindViewHolder(ViewHolder holder, final int position) {
final ObjectIncome objIncome = myItems.get(position);
String content = "<b>lalalla</b>";
holder.tvContent.setText(Html.fromHtml(content));
}
}
The problem is, let's say I have 10 items inside the RecyclerView. When I checked the checkbox on item 1,2,3 then I scroll down the RecyclerView, suddenly some of the other items eg items 8,9 is checked. And when I scroll up again, item 1 and 3 is checked but not item 2. Any idea why this happen?

That's an expected behavior. You are not setting your checkbox selected or not. You are selecting one and View holder keeps it selected. You can add a boolean variable into your ObjectIncome object and keep your item's selection status.
You may look at my example. You can do something like that:
public class AdapterTrashIncome extends RecyclerView.Adapter<AdapterTrashIncome.ViewHolder> {
private ArrayList<ObjectIncome> myItems = new ArrayList<>();
public AdapterTrashIncome(ArrayList<ObjectIncome> getItems, Context context){
try {
mContext = context;
myItems = getItems;
}catch (Exception e){
Log.e(FILE_NAME, "51: " + e.toString());
e.printStackTrace();
}
}
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView tvContent;
public CheckBox cbSelect;
public ViewHolder(View v) {
super(v);
tvContent = (TextView) v.findViewById(R.id.tvContent);
cbSelect = (CheckBox) v.findViewById(R.id.cbSelect);
}
}
#Override
public void onBindViewHolder(ViewHolder holder, final int position) {
final ObjectIncome objIncome = myItems.get(position);
String content = "<b>lalalla</b>";
holder.tvContent.setText(Html.fromHtml(content));
//in some cases, it will prevent unwanted situations
holder.cbSelect.setOnCheckedChangeListener(null);
//if true, your checkbox will be selected, else unselected
holder.cbSelect.setChecked(objIncome.isSelected());
holder.cbSelect.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
//set your object's last status
objIncome.setSelected(isChecked);
}
});
}
}

In short, its because of recycling the views and using them again!
how can you avoid that :
1.In onBindViewHolder check whether you should check or uncheck boxes.
don't forget to put both if and else
if (...)
holder.cbSelect.setChecked(true);
else
holder.cbSelect.setChecked(false);
Put a listener for check box! whenever its checked statues changed, update the corresponding object too in your myItems array ! so whenever a new view is shown, it read the newest statue of the object.

Just add two override methods of RecyclerView
#Override
public long getItemId(int position) {
return position;
}
#Override
public int getItemViewType(int position) {
return position;
}

Use this only if you have limited number of items in your RecyclerView.
I tried using boolean value in model and keep the CheckBox status, but it did not help in my case. What worked for me is this.setIsRecyclable(false);
public class ComponentViewHolder extends RecyclerView.ViewHolder {
public MyViewHolder(View itemView) {
super(itemView);
...
this.setIsRecyclable(false);
}
More explanation on this can be found here
NOTE: This is a workaround. To use it properly you can refer the document which states
Calls to setIsRecyclable() should always be paired (one call to setIsRecyclabe(false) should always be matched with a later call to setIsRecyclable(true)). Pairs of calls may be nested, as the state is internally reference-counted.
I don't know how to do this in code, if someone can provide more code on this.

You can use Model class to keep track of each RecyclerView item's CheckBox. Full reference is from : RecyclerView Checkbox Android
setTag and getTag is used to keep track of CheckBox status. Check full reference link for more information. It also teaches how to send checked items to Next Activity.
Make Model class:
public class Model {
private boolean isSelected;
private String animal;
public String getAnimal() {
return animal;
}
public void setAnimal(String animal) {
this.animal = animal;
}
public boolean getSelected() {
return isSelected;
}
public void setSelected(boolean selected) {
isSelected = selected;
}
}
Create integer.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<integer name="btnplusview">1</integer>
<integer name="btnpluspos">2</integer>
</resources>
Finally RecyclerView.Adapter looks like this:
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyViewHolder> {
private LayoutInflater inflater;
public static ArrayList<Model> imageModelArrayList;
private Context ctx;
public CustomAdapter(Context ctx, ArrayList<Model> imageModelArrayList) {
inflater = LayoutInflater.from(ctx);
this.imageModelArrayList = imageModelArrayList;
this.ctx = ctx;
}
#Override
public CustomAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = inflater.inflate(R.layout.rv_item, parent, false);
MyViewHolder holder = new MyViewHolder(view);
return holder;
}
#Override
public void onBindViewHolder(final CustomAdapter.MyViewHolder holder, int position) {
holder.checkBox.setText("Checkbox " + position);
holder.checkBox.setChecked(imageModelArrayList.get(position).getSelected());
holder.tvAnimal.setText(imageModelArrayList.get(position).getAnimal());
// holder.checkBox.setTag(R.integer.btnplusview, convertView);
holder.checkBox.setTag(position);
holder.checkBox.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Integer pos = (Integer) holder.checkBox.getTag();
Toast.makeText(ctx, imageModelArrayList.get(pos).getAnimal() + " clicked!", Toast.LENGTH_SHORT).show();
if (imageModelArrayList.get(pos).getSelected()) {
imageModelArrayList.get(pos).setSelected(false);
} else {
imageModelArrayList.get(pos).setSelected(true);
}
}
});
}
#Override
public int getItemCount() {
return imageModelArrayList.size();
}
class MyViewHolder extends RecyclerView.ViewHolder {
protected CheckBox checkBox;
private TextView tvAnimal;
public MyViewHolder(View itemView) {
super(itemView);
checkBox = (CheckBox) itemView.findViewById(R.id.cb);
tvAnimal = (TextView) itemView.findViewById(R.id.animal);
}
}
}

Using Kotlin the only thing which solved this problem for me was to clear the OnCheckedChangeListener before setting the variable and then create a new OnCheckedChangeListener after checked has been set.
I do the following in my RecyclerView.ViewHolder
task.setOnCheckedChangeListener(null)
task.isChecked = item.status
task.setOnCheckedChangeListener { _: CompoundButton, checked: Boolean ->
item.status = checked
...
do more stuff
...
}

I recommend that not to use checkBox.setOnCheckedChangeListener in RecyclerView.Adapter. Because on scrolling RecyclerView, checkBox.setOnCheckedChangeListener will be fired by adapter. It's not safe. Instead, use checkBox.setOnClickListener to interact with user inputs.
For example:
public void onBindViewHolder(final ViewHolder holder, int position) {
...
holder.checkBoxAdapterTasks.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
boolean isChecked = holder.checkBoxAdapterTasks.isChecked();
if (isChecked) {
// checkBox clicked and checked
} else {
// checkBox clicked and unchecked
}
}
});
}

It might be very late but the simplest of all answers is to assign the check state in bind ViewHolder. RecyclerView will check and apply that state when reusing.
override fun onBindViewHolder(holder: BaseViewHolder, position: Int) {
binding.checkbox.isChecked = item.isChecked
}
Maintain that state in your class. (Assign a initial default value)
class MyItem {
val isChecked: Boolean = false
}
onClickListener do your stuff and assign the state to class variable. In my case, I have delegate clickListener in view. So, it is like this in Adapter:
binding.checkbox.setOnClickListener {
onClickListener.invoke(item)
}
Then, in view, I am doing this:
val adapter = MyItem { item->
viewModel.checkedContactsList.value?.let { list ->
if (list.contains(item)) {
item.isChecked = false
list.remove(item)
} else {
item.isChecked = true
list.add(item)
}
}
}

In my case this worked.
#Override
public void onViewRecycled(MyViewHolder holder) {
holder.checkbox.setChecked(false); // - this line do the trick
super.onViewRecycled(holder);
}

As stated above, the checked state of the object should be included within object properties. In some cases you may need also to change the object selection state by clicking on the object itself and let the CheckBox inform about the actual state (either selected or unselected). The checkbox will then use the state of the object at the actual position of the given adapter which is (by default/in most cases) the position of the element in the list.
Check the snippet below, it may be useful.
import android.content.Context;
import android.graphics.Bitmap;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.ImageView;
import java.io.File;
import java.io.IOException;
import java.util.List;
public class TakePicImageAdapter extends RecyclerView.Adapter<TakePicImageAdapter.ViewHolder>{
private Context context;
private List<Image> imageList;
public TakePicImageAdapter(Context context, List<Image> imageList) {
this.context = context;
this.imageList = imageList;
}
#Override
public TakePicImageAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view= LayoutInflater.from(context).inflate(R.layout.image_item,parent,false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(final TakePicImageAdapter.ViewHolder holder, final int position) {
File file=new File(imageList.get(position).getPath());
try {
Bitmap bitmap= MediaStore.Images.Media.getBitmap(context.getContentResolver(), Uri.fromFile(file));
holder.image.setImageBitmap(bitmap
);
} catch (IOException e) {
e.printStackTrace();
}
holder.selectImage.setOnCheckedChangeListener(null);
holder.selectImage.setChecked(imageList.get(position).isSelected());
holder.selectImage.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
holder.selectImage.setChecked(isChecked);
imageList.get(position).setSelected(isChecked);
}
});
holder.image.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (imageList.get(position).isSelected())
{
imageList.get(position).setSelected(false);
holder.selectImage.setChecked(false);
}else
{
imageList.get(position).setSelected(true);
holder.selectImage.setChecked(true);
}
}
});
}
#Override
public int getItemCount() {
return imageList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
public ImageView image;public CheckBox selectImage;
public ViewHolder(View itemView) {
super(itemView);
image=(ImageView)itemView.findViewById(R.id.image);
selectImage=(CheckBox) itemView.findViewById(R.id.ch);
}
}
}

Use an array to hold the state of the items
In the adapter use a Map or a SparseBooleanArray (which is similar to a Map, but is a key-value pair of int and boolean) to store the state of all the items in our list of items and then use the keys and values to compare when toggling the checked state.
In the Adapter create a SparseBooleanArray:
// sparse boolean array for checking the state of the items
private SparseBooleanArray itemStateArray = new SparseBooleanArray();
Then in the item click handler onClick() use the state of the items in the itemStateArray to check before toggling, here is an example
#Override
public void onClick(View v) {
int adapterPosition = getAdapterPosition();
if (!itemStateArray.get(adapterPosition, false)) {
mCheckedTextView.setChecked(true);
itemStateArray.put(adapterPosition, true);
} else {
mCheckedTextView.setChecked(false);
itemStateArray.put(adapterPosition, false);
}
}
Also, use sparse boolean array to set the checked state when the view is bound:
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
holder.bind(position);
}
#Override
public int getItemCount() {
if (items == null) {
return 0;
}
return items.size();
}
void loadItems(List<Model> tournaments) {
this.items = tournaments;
notifyDataSetChanged();
}
class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
CheckedTextView mCheckedTextView;
ViewHolder(View itemView) {
super(itemView);
mCheckedTextView = (CheckedTextView) itemView.findViewById(R.id.checked_text_view);
itemView.setOnClickListener(this);
}
// use the sparse boolean array to check
void bind(int position) {
if (!itemStateArray.get(position, false)) {
mCheckedTextView.setChecked(false);}
else {
mCheckedTextView.setChecked(true);
}
}
}
and final adapter will be like this.

This will happened when use setOnCheckedChangeListener instead of that use setObClickListener and inside that just do this easy handle:
if (list.get(position).isCheck()) {
list.get(position).setCheck(false);
} else {
list.get(position).setCheck(true);
}
Note: in your list model add one boolean variable with name check and set getter and setter for that , in above case mine is setCheck and isCheck

This is a Kotlin Solution That Worked for Me
class SpecialtyFragmentRecyclerAdapter : RecyclerView.Adapter<SpecialtyFragmentRecyclerAdapter.SpecialtyViewHolder>(){
private var _specialtySet = mutableSetOf(
"Yoruba Attires",
"Hausa Attires",
"Senator",
"Embroidery",
"Africa Fashion",
"School Uniform",
"Military and Para-Military Uniforms",
"Igbo Attires",
"South-South Attires",
"Kaftans",
"Contemporary",
"Western Fashion",
"Caps"
).toSortedSet()
val specialtySet: Set<String> get() = _specialtySet
val savedSpecialtySet = mutableSetOf<String>().toSortedSet()
inner class SpecialtyViewHolder(
var itemBinding: SpecialtyFragmentRecyclerItemBinding
) :
RecyclerView.ViewHolder(itemBinding.root) {
fun bind(specialty: String) = with(itemBinding) {
specialtyFragmentYorubaAttiresCheckBox.text = specialty
specialtyFragmentYorubaAttiresCheckBox.isChecked = savedSpecialtySet.contains(specialty)
//AREA OF INTEREST
//Either Setting the CheckBox onCheckChangeListener to works
specialtyFragmentYorubaAttiresCheckBox.setOnCheckedChangeListener(null)
specialtyFragmentYorubaAttiresCheckBox.setOnCheckedChangeListener(
CompoundButton.OnCheckedChangeListener { buttonView, isChecked ->
if (buttonView.isPressed) { //OR this Also Works {Check if the Button is Pressed Before verifying the Checked State}
if (isChecked) {
savedSpecialtySet.add(specialty) //Perform Your Operation for Checked State
} else {
savedSpecialtySet.remove(specialty) //Perform Your Operation for unChecked State
}
}
}
)
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): SpecialtyViewHolder {
val viewBinding = SpecialtyFragmentRecyclerItemBinding
.inflate(LayoutInflater.from(parent.context), parent, false)
return SpecialtyViewHolder(viewBinding)
}
override fun onBindViewHolder(holder: SpecialtyViewHolder, position: Int) {
val specialty = _specialtySet.elementAt(position)
holder.bind(specialty)
}
override fun getItemCount(): Int {
return _specialtySet.size
}
fun populateList(list: MutableList<String>) {
savedSpecialtySet.addAll(list)
_specialtySet.addAll(list)
notifyDataSetChanged()
}
fun addNewSpecialty(specialty: String) {
_specialtySet.add(specialty.trim())
savedSpecialtySet.add(specialty.trim())
notifyDataSetChanged()
}
fun removeSpecialty(element: String) {
_specialtySet.remove(element)
savedSpecialtySet.remove(element)
notifyDataSetChanged()
}
}

I had the same problem in a RecyclerView list with switches, and solved it using #oguzhand answer, but with this code inside the checkedChangeListener:
if (buttonView.isPressed()) {
if (isChecked) {
group.setSelected(true);
} else {
group.setSelected(false);
}
} else {
if (isChecked) {
buttonView.setChecked(false);
} else {
buttonView.setChecked(true);
}
}
Where 'group' is the entity I want to select/deselect.

I've had the same issue. When I was clicking on item's - toggle buttons become checked in my RecyclerView. Toggle buttons appeared in every 10th item (for example if it was clicked in item with 0 index, items with 9, 18, 27 indexes were getting clicked too).
My code in onBindViewHolder was:
if (newsItems.get(position).getBookmark() == 1) {
holder.getToggleButtonBookmark().setChecked(true);
}
But then I added else statement:
/**
* Else statement prevents auto toggling.
*/
if (newsItems.get(position).getBookmark() == 1) {
holder.getToggleButtonBookmark().setChecked(true);
} else{
holder.getToggleButtonBookmark().setChecked(false);
}
And the problem was solved!

You need to separate onBindViewHolder(logic) interactions with CheckBox and user interactions with checkBox. I used OnCheckedChangeListener for user interactions (obviously) and ViewHolder.bind() for logic, that's why you need to set checked listener to null before setting up holder and after holder is ready - configure checked listener for user interactions.
boolean[] checkedStatus = new boolean[numberOfRows];
#Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
final ViewHolderItem itemHolder = (ViewHolderItem) holder;
// holder.bind should not trigger onCheckedChanged, it should just update UI
itemHolder.checkBox.setOnCheckedChangeListener(null);
itemHolder.bind(position);
itemHolder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
checkedStatus[holder.getAdapterPosition()] = true;
performCheckedActions(); //your logic here
} else {
checkedStatus[holder.getAdapterPosition()] = false;
performUncheckedActions(); //your logic here
}
}
});
}
public void bind(int position) {
boolean checked = checkedStatus[position];
if (checked) {
checkBox.setChecked(false);
} else {
checkBox.setChecked(true);
}
}

I solved this problem by creating a static global array and using it in onBindViewHolder
RecyclerView.Adapter realization class:
In which I created all global variables/objects needed.
public class RVAdapter extends RecyclerView.Adapter<RVAdapter.PersonViewHolder> {
private Context context;
...
public static class PersonViewHolder extends RecyclerView.ViewHolder {
CardView cv;
TextView question, category;
TextView personAge;
ImageView upvote;
Button b1;
public static int k;
private int visibleThreshold = 5;
public static int i = 0;
static int check[]; //Static array
PersonViewHolder(View itemView, int i) {
super(itemView);
if(i == PersonViewHolder.k) {
b1 = (Button) itemView.findViewById(R.id.loadmore);
} else {
cv = (CardView) itemView.findViewById(R.id.cv);
question = (TextView) itemView.findViewById(R.id.question);
category = (TextView) itemView.findViewById(R.id.text_categ);
personAge = (TextView) itemView.findViewById(R.id.text1);
upvote = (ImageView) itemView.findViewById(R.id.upvote);
}
}
}
...
}
Here (in contructor of RVAdapter class) I gave size to the array equals to the size of items I'm going to display in the RecyclerView:
List<Person> persons;
RVAdapter(List<Person> persons){
this.persons = persons;
PersonViewHolder.check = new int[persons.size()];
PersonViewHolder.k = persons.size();
}
In onBindViewHolder I applied this concept on a button. When I click on a button - the background image of the button changes.
Object of button I used is names as "upvote", as "i" holds the position of each item in RecyclerView. I used it as an index of array which is working as a flag and which is keeping track of status of elements.
#Override
public void onBindViewHolder(final PersonViewHolder personViewHolder, final int i) {
if (i == PersonViewHolder.k) {
personViewHolder.b1.setText("load more");
} else {
personViewHolder.question.setText(persons.get(i).name);
personViewHolder.personAge.setText(persons.get(i).age);
if (personViewHolder.check[i] == 0) {
personViewHolder.upvote.setBackgroundResource(R.drawable.noupvote);
} else {
personViewHolder.upvote.setBackgroundResource(R.drawable.upvote);
}
personViewHolder.upvote.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (personViewHolder.check[i] == 0) {
personViewHolder.check[i] = 1;
personViewHolder.upvote.setBackgroundResource(R.drawable.upvote);
} else {
personViewHolder.check[i] = 0;
personViewHolder.upvote.setBackgroundResource(R.drawable.noupvote);
}
}
});
// personViewHolder.personPhoto.setImageResource(persons.get(i).photoId);
}
}

Okay there is a lot of answers here. But I will post my code and I will simply explain what I did... it maybe help juniors like me :D.
Objective:
We will create a list of RecyclerView that has CheckBox and RadioButton, something like this:
Model for list item with all needed data:
public class ModelClass {
private String time;
private boolean checked;
private boolean free;
private boolean paid;
public TherapistScheduleModel(String time, boolean checked, boolean free, boolean paid) {
this.time = time;
this.checked = checked;
this.free = free;
this.paid = paid;
}
public boolean isFree() {
return free;
}
public void setFree(boolean free) {
this.free = free;
}
public boolean isPaid() {
return paid;
}
public void setPaid(boolean paid) {
this.paid = paid;
}
public String getTime() {
return time;
}
public void setTime(String time) {
this.time = time;
}
public boolean getChecked() {
return checked;
}
public void setChecked(boolean checked) {
this.checked= checked;
}
}
My RecyclerView.Adapter amazing realization:
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private Context context;
private ListAllListeners listAllListeners;
private ArrayList<ModelClass> mDataList;
public MyAdapter(
Context context,
ArrayList<ModelClass> mDataList,
ListAllListeners listAllListeners
) {
this.mDataList = mDataList;
this.listAllListeners = listAllListeners;
this.context = context;
}
#NonNull
#Override
public MyViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
View view = inflater.inflate(R.layout.single_view, parent, false);
return new MyViewHolder(view);
}
#Override
public int getItemCount() {
if (mDataList != null) {
return mDataList.size();
} else {
return 0;
}
}
#Override
public void onBindViewHolder(#NonNull final MyViewHolder holder, final int position) {
// important to:
// setOnCheckedChangeListener to 'null'
holder.checkBoxTime.setOnCheckedChangeListener(null);
holder.freeRB.setOnCheckedChangeListener(null);
holder.paidRB.setOnCheckedChangeListener(null);
// Check Box
holder.checkBoxTime.setText(mDataList.get(holder.getAdapterPosition()).getTime());
// Here we check if the item is checked or not from the model.
if(mDataList.get(holder.getAdapterPosition()).getChecked()) {
holder.checkBoxTime.setChecked(true);
} else {
holder.checkBoxTime.setChecked(false);
}
holder.checkBoxTime.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
if (b) {
mDataList.get(holder.getAdapterPosition()).setChecked(true);
listAllListeners.onItemCheck(holder.checkBoxTime.getText().toString(), holder.getAdapterPosition());
} else {
mDataList.get(holder.getAdapterPosition()).setChecked(false);
listAllListeners.onItemUncheck(holder.checkBoxTime.getText().toString(), holder.getAdapterPosition());
}
}
});
// Radio Buttons
if(mDataList.get(holder.getAdapterPosition()).isFree()) {
holder.freeRB.setChecked(true);
} else {
holder.freeRB.setChecked(false);
}
holder.freeRB.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
if (b) {
mDataList.get(holder.getAdapterPosition()).setFree(true);
listAllListeners.onFreeCheck(holder.freeRB.getText().toString(), holder.getAdapterPosition());
} else {
mDataList.get(holder.getAdapterPosition()).setFree(false);
listAllListeners.onFreeUncheck(holder.freeRB.getText().toString(), holder.getAdapterPosition());
}
}
});
// And so on to paidRB
}
/**
* Here is a list of clicked listeners to use them as you want ;).
* You can get a list of checked or unchecked of all.
*/
public interface ListAllListeners {
void onItemCheck(String checkBoxName, int position);
void onItemUncheck(String checkBoxName, int position);
void onFreeCheck(String name, int pos);
void onFreeUncheck(String name, int pos);
void onPaidCheck(String name, int pos);
void onPaidUncheck(String name, int pos);
}
class MyViewHolder extends RecyclerView.ViewHolder {
CheckBox checkBoxTime;
RadioButton freeRB, paidRB;
MyViewHolder(View itemView) {
super(itemView);
checkBoxTime = itemView.findViewById(R.id.timeCheckBox);
freeRB = itemView.findViewById(R.id.freeRadioBtn);
paidRB = itemView.findViewById(R.id.paidRadioBtn);
}
}
}
In Activity you get them something like this:
myAdapter = new MyAdapter(this, mDataList, new MyAdapter.ListAllListeners() {
#Override
public void onItemCheck(String checkBoxName, int position) {
Toast.makeText(getActivity(), "" + checkBoxName + " " + position, Toast.LENGTH_SHORT).show();
}
#Override
public void onItemUncheck(String checkBoxName, int position) {
Toast.makeText(getActivity(), "" + checkBoxName + " " + position, Toast.LENGTH_SHORT).show();
}
#Override
public void onFreeCheck(String name, int position) {
Toast.makeText(getActivity(), "" + name + " " + position, Toast.LENGTH_SHORT).show();
}
#Override
public void onFreeUncheck(String name, int position) {
Toast.makeText(getActivity(), "" + name + " " + position, Toast.LENGTH_SHORT).show();
}
#Override
public void onPaidCheck(String name, int position) {
Toast.makeText(getActivity(), "" + name + " " + position, Toast.LENGTH_SHORT).show();
}
#Override
public void onPaidUncheck(String name, int position) {
Toast.makeText(getActivity(), "" + name + " " + position, Toast.LENGTH_SHORT).show();
}
});

this is due to again and again creating view ,best option is clear cache before setting adapter
recyclerview.setItemViewCacheSize(your array.size());

In onBindViewHolder for views (checkbox, radio, switch, ...) you should setOnCheckedChangeListener(null) before and after new creation. For example:
public void onBindViewHolder(#NonNull ViewHolder holder,
int position) {
...
holder.switchCompat.setOnCheckedChangeListener(null);
...
holder.switchCompat.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton compoundButton,
boolean b) {
// TODO: 10/23/2022 do something
}
});
}

Solution is while CheckBox is checked. Need to store this separate list, and use that list to populate CheckBox in RecyclerView.
You can refer this link.

Complete example:
public class ChildAddressAdapter extends RecyclerView.Adapter<ChildAddressAdapter.CartViewHolder> {
private Activity context;
private List<AddressDetail> addressDetailList;
private int selectedPosition = -1;
public ChildAddressAdapter(Activity context, List<AddressDetail> addressDetailList) {
this.context = context;
this.addressDetailList = addressDetailList;
}
#NonNull
#Override
public CartViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(context);
View myView = inflater.inflate(R.layout.address_layout, parent, false);
return new CartViewHolder(myView);
}
#Override
public void onBindViewHolder(#NonNull CartViewHolder holder, int position) {
holder.adress_checkbox.setOnClickListener(view -> {
selectedPosition = holder.getAdapterPosition();
notifyDataSetChanged();
});
if (selectedPosition==position){
holder.adress_checkbox.setChecked(true);
}
else {
holder.adress_checkbox.setChecked(false);
}
}
#Override
public int getItemCount() {
return addressDetailList.size();
}
class CartViewHolder extends RecyclerView.ViewHolder {
TextView address_text,address_tag;
CheckBox adress_checkbox;
CartViewHolder(View itemView) {
super(itemView);
address_text = itemView.findViewById(R.id.address_text);
address_tag = itemView.findViewById(R.id.address_tag);
adress_checkbox = itemView.findViewById(R.id.adress_checkbox);
}
}
}

public class TagYourDiseaseAdapter extends RecyclerView.Adapter<TagYourDiseaseAdapter.OrderHistoryViewHolder> {
private ReCyclerViewItemClickListener mRecyclerViewItemClickListener;
private Context mContext;
List<Datum> deviceList = Collections.emptyList();
/**
* Initialize the values
*
* #param context : context reference
* #param devices : data
*/
public TagYourDiseaseAdapter(Context context, List<Datum> devices,
ReCyclerViewItemClickListener mreCyclerViewItemClickListener) {
this.mContext = context;
this.deviceList = devices;
this.mRecyclerViewItemClickListener = mreCyclerViewItemClickListener;
}
/**
* #param parent : parent ViewPgroup
* #param viewType : viewType
* #return ViewHolder
* <p>
* Inflate the Views
* Create the each views and Hold for Reuse
*/
#Override
public TagYourDiseaseAdapter.OrderHistoryViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_tag_disease, parent, false);
TagYourDiseaseAdapter.OrderHistoryViewHolder myViewHolder = new TagYourDiseaseAdapter.OrderHistoryViewHolder(view);
return myViewHolder;
}
/**
* #param holder : view Holder
* #param position : position of each Row set the values to the views
*/
#Override
public void onBindViewHolder(final TagYourDiseaseAdapter.OrderHistoryViewHolder holder, final int position) {
Picasso.with(mContext).load(deviceList.get(position).getIconUrl()).into(holder.document);
holder.name.setText(deviceList.get(position).getDiseaseName());
holder.radioButton.setOnCheckedChangeListener(null);
holder.radioButton.setChecked(deviceList.get(position).isChecked());
//if true, your checkbox will be selected, else unselected
//holder.radioButton.setChecked(objIncome.isSelected());
holder.radioButton.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
deviceList.get(position).setChecked(isChecked);
}
});
}
#Override
public int getItemCount() {
return deviceList.size();
}
/**
* Create The view First Time and hold for reuse
* View Holder for Create and Hold the view for ReUse the views instead of create again
* Initialize the views
*/
public class OrderHistoryViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
ImageView document;
TextView name;
CheckBox radioButton;
public OrderHistoryViewHolder(View itemView) {
super(itemView);
document = itemView.findViewById(R.id.img_tag);
name = itemView.findViewById(R.id.text_tag_name);
radioButton = itemView.findViewById(R.id.rdBtn_tag_disease);
radioButton.setOnClickListener(this);
//this.setIsRecyclable(false);
}
#Override
public void onClick(View view) {
mRecyclerViewItemClickListener.onItemClickListener(this.getAdapterPosition(), view);
}
}
}

If it is not late; this is actually RecyclerView general problem. You can put your RecyclerView into a NestedScrollView and then add one line code to your adapter. All is done.
In your activity or fragment;
<androidx.core.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
</androidx.core.widget.NestedScrollView>
And in your activity where you set adapter add this:
ViewCompat.setNestedScrollingEnabled(recyclerView, false);
LinearLayoutManager layoutManager = new LinearLayoutManager(getContext());
// your adapter code...
recyclerView.setAdapter(textSearchAdapter);

I faced the similar issue while using checkbox inside recycler view. After some detail analysis I got the root cause. let's look at the code once
In onBindViewHolder the line "holder.cbSelect.setChecked(yourList.isSelected());"
will always execute.
If we scroll up or scroll down the page, the onBindViewHolder will get called. As soon as onBindViewHolder will get called "holder.cbSelect.setChecked(yourList.isSelected());" will get tiggered and as a result
"holder.cbSelect.setOnCheckedChangeListener" will also get called and it will change the checkbox state, even if you have not changed the checkbox state. The reason is simple that it found checkbox state is changed from your updated list (yourList.isSelected()) which you select or dis-select the check box .
Now as a solution in override method of "public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)" method we need to add one condition that is
holder.cbSelect.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (buttonView.isPressed()) {
//Check box state changed by user
//update your list based on checkbox value
// yourList.setSelected(isChecked);
}
}
});

What worked for me is to nullify the listeners on the viewHolder when the view is going to be recycled (onViewRecycled):
override fun onViewRecycled(holder: AttendeeViewHolder) {
super.onViewRecycled(holder)
holder.itemView.hasArrived.setOnCheckedChangeListener(null);
holder.itemView.edit.setOnClickListener { null }
}

Adding setItemViewCacheSize(int size) to RecyclerView and passing size of list solved my problem.
My code:
mrecyclerview.setItemViewCacheSize(mOrderList.size());
mBinding.mrecyclerview.setAdapter(mAdapter);
Source: link

How to manage multiple positions in RecyclerView OnClickListener

I want to know how I can get access to other elements of the array in this onclicklistener for a Recycler view. Specifically, I want to be able to change the enabled state of a position other than the current Listener position, but within the click event.
I'm trying to make it such that if three colors are checked (those are check boxes) every box not checked will be disabled until the number of boxes checked is < 3.
The for-loops I have I wrote make sense, but I can't programmatically change the enabled state within the onClickListener for some reason.
private void buildRecyclerView() {
mRecyclerView = findViewById(R.id.recyclerView);
mRecyclerView.setHasFixedSize(true);
mLayoutManager = new LinearLayoutManager(this);
mAdapter = new ExampleAdapter(mExampleList);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
mAdapter.setOnItemClickListener(new ExampleAdapter.OnItemClickListener() {
#Override
public void onItemClick(int position) {
boolean checkedState;
if (mExampleList.get(position).getChecked1() == false) {
checkedState = true;
} else {
checkedState = false;
}
changeItem(position, checkedState);
int sum = 0;
for (int i = 0; i < stringArray.length; i++) {
Boolean checked = mExampleList.get(i).getChecked1();
if (checked == true) {
sum = sum + 1;
}
}
for (int i = 0; i < stringArray.length; i++) {
Boolean checked = mExampleList.get(i).getChecked1();
if (!checked && sum == 3) {
mExampleList.get(i).setEnabled1(false);
} else {
mExampleList.get(i).setEnabled1(true);
}
}
}
});
}
adapter
public class ExampleAdapter extends RecyclerView.Adapter<ExampleAdapter.ExampleViewHolder> {
private ArrayList<ExampleItem> mExampleList;
private OnItemClickListener mListener;
public interface OnItemClickListener {
void onItemClick(int position);
}
public void setOnItemClickListener(OnItemClickListener listener) {
mListener = listener;
}
public static class ExampleViewHolder extends RecyclerView.ViewHolder {
public CheckBox mCheckBox;
public ExampleViewHolder(#NonNull View itemView, final OnItemClickListener listener) {
super(itemView);
mCheckBox = itemView.findViewById(R.id.checkBox);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (listener != null){
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION);
listener.onItemClick(position);
}
}
});
}
}
public ExampleAdapter(ArrayList<ExampleItem> exampleList) {
mExampleList = exampleList;
}
#NonNull
#Override
public ExampleViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.example_item, parent, false);
ExampleViewHolder evh = new ExampleViewHolder(v, mListener);
return evh;
}
#Override
public void onBindViewHolder(#NonNull ExampleViewHolder holder, int position) {
ExampleItem currentItem = mExampleList.get(position);
holder.mCheckBox.setText(currentItem.getCheckText());
holder.mCheckBox.setEnabled(currentItem.getEnabled1());
holder.mCheckBox.setChecked(currentItem.getChecked1());
}
#Override
public int getItemCount() {
return mExampleList.size();
}
}
Item Class
public class ExampleItem {
public String mCheckText;
public Boolean mEnabled;
public Boolean mChecked;
public ExampleItem(String mCheckText, Boolean mEnabled, Boolean mChecked) {
this.mCheckText = mCheckText;
this.mEnabled = mEnabled;
this.mChecked = mChecked;
}
public ExampleItem(String mCheckText) {
this.mCheckText = mCheckText;
}
public String getCheckText() {
return mCheckText;
}
public void setCheckText(String mCheckText) {
this.mCheckText = mCheckText;
}
public Boolean getEnabled1() {
return mEnabled;
}
public void setEnabled1(Boolean mEnabled) {
this.mEnabled = mEnabled;
}
public Boolean getChecked1() {
return mChecked;
}
public void setChecked1(Boolean mChecked) {
this.mChecked = mChecked;
}
}
In other words, I am trying to make everything below blue disabled until I uncheck Red, Green, or Blue!

Try the following:
In adapter, add below codes:
private int selectedCount = 0;
public int getSelectedCount() {
return selectedCount;
}
public void setSelectedCount(int selectedCount) {
this.selectedCount = selectedCount;
notifyDataSetChanged();
}
and change onBindViewHolder() to:
#Override
public void onBindViewHolder(#NonNull ExampleViewHolder holder, int position) {
ExampleItem currentItem = mExampleList.get(position);
holder.mCheckBox.setText(currentItem.getCheckText());
holder.mCheckBox.setChecked(currentItem.getChecked1());
if ((selectedCount == 3)) holder.mCheckBox.setEnabled(currentItem.getChecked1());
else holder.mCheckBox.setEnabled(true);
}
Then in Activity/Fragment, change mAdapter.setOnItemClickListener(new ExampleAdapter.OnItemClickListener()... to:
mAdapter.setOnItemClickListener(new ExampleAdapter.OnItemClickListener() {
#Override
public void onItemClick(int position) {
boolean checkedState;
int selectedCount = mAdapter.getSelectedCount();
if ((selectedCount != 3) || (mExampleList.get(position).getChecked1())) {
if (mExampleList.get(position).getChecked1() == false) {
checkedState = true;
selectedCount++;
} else {
checkedState = false;
selectedCount--;
}
changeItem(position, checkedState);
mAdapter.setSelectedCount(selectedCount);
}
}
});
Pls note that no need to have mEnabled field in the ExampleItem class. Hope that helps!
Explanantion:
About the onClick:- This is because CheckBox totally covered the layout, so itemView cannot recieve the click event. About RecyclerView:- The idea is simple, after modified the data set [not list, here I refer to the mExampleList and also the selectedCount], then call notifyDataSetChanged() which will redraw all recycler item views.

You would need to create a setter function for your 'mExampleList' in your Adpater class, to update the dataset that the adapter is using. It obviously does not change anything, if you make changes to 'mExampleList' in your activity, without updating the list used by the Adapter.
So at the end of your click listener you would have something like that:
mAdapter.setExampleList(mExampleList)
mAdapter.notifyDataSetChanged()

Setting RecyclerView Header without overriding first element

Hello i have a recyclerView which displays cards containing data fetched from mysql with retrofit. In my adapter, I was able to set the first card to a static element which is the user's profile picture as suggested by the accepted answer here. However they didn't notice that the method overrides the former first element (element at position 0). The first element gets replaced by the static view but i don't want that. I want
static card,
cardview 0,
cardview 1,
cardview 2,
etc
Any ideas? thanks

There isn't an easy way like listview.addHeaderView() but you can achieve this by adding a type to your adapter for header.
Here is an example
public class HeaderAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private static final int TYPE_HEADER = 0;
private static final int TYPE_ITEM = 1;
String[] data;
public HeaderAdapter(String[] data) {
this.data = data;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_ITEM) {
//inflate your layout and pass it to view holder
return new VHItem(null);
} else if (viewType == TYPE_HEADER) {
//inflate your layout and pass it to view holder
return new VHHeader(null);
}
throw new RuntimeException("there is no type that matches the type " + viewType + " + make sure your using types correctly");
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if (holder instanceof VHItem) {
String dataItem = getItem(position);
//cast holder to VHItem and set data
} else if (holder instanceof VHHeader) {
//cast holder to VHHeader and set data for header.
}
}
#Override
public int getItemCount() {
return data.length + 1;
}
#Override
public int getItemViewType(int position) {
if (isPositionHeader(position))
return TYPE_HEADER;
return TYPE_ITEM;
}
private boolean isPositionHeader(int position) {
return position == 0;
}
private String getItem(int position) {
return data[position - 1];
}
class VHItem extends RecyclerView.ViewHolder {
TextView title;
public VHItem(View itemView) {
super(itemView);
}
}
class VHHeader extends RecyclerView.ViewHolder {
Button button;
public VHHeader(View itemView) {
super(itemView);
}
}
}

Use 'viewType' in 'RecyclerView.Adapter'.
onCreateViewHolder in RecyclerView
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
int layout = -1;
switch (viewType) {
case RecyclerViewItem.USER_PROFILE:
layout = R.layout.driving_item;
break;
case RecyclerViewItem.OTHER_USER_PROFILE:
layout = R.layout.date_item;
break;
case RecyclerViewItem.DATE:
layout = R.layout.send_button_item;
break;
}
View v = LayoutInflater.from(context).inflate(layout, parent, false);
return new MyViewHolder(v);
}
onBindViewHolder in RecyclerView
#Override
public void onBindViewHolder(final MyViewHolder myViewHolder, final int position) {
final int pos = myViewHolder.getAdapterPosition();
if (pos == -1) {
return;
}
final RecyclerViewItem item = ArrayList.get(pos);
switch (item.getType()) {
case RecyclerViewItem.USER_PROFILE:
//By type you want to do differently.
break;
case RecyclerViewItem.OTHER_USER_PROFILE:
//By type you want to do differently.
break;
case RecyclerViewItem.DATE:
//By type you want to do differently.
break;
}
}
f you have any additional questions, please let me know by comment.

IndexOutOfBoundsException in RecyclerAdapter with Multiple View Types

I'm getting an IndexOutOfBoundsException when attempting to return the view type as a function of the position of the data in my array. I have two sources of data. One is an advertisement, and the other is a list of names and locations. Do I need to combine the arrays into one single array before processing it in the RecyclerAdapter? I'd rather not, especially if in principle they could be different types, i.e. images versus text. My getItemCount() method properly returns the summed size of the two arrays. Why am I getting this exception? How can I achieve the desired result of showing data from two different sources in two different view types?
My main activity:
public class MainActivity extends AppCompatActivity {
private ArrayList<Object> getPresidentsArrayList() {
ArrayList<Object> items = new ArrayList<>();
items.add(new President("George Washington", "Mount Vernon"));
items.add(new President("John Adams", "Braintree"));
items.add(new President("Thomas Jefferson", "Monticello"));
items.add(new President("James Madison", "Port Conway"));
return items;
}
private ArrayList<Object> getAdsArrayList() {
ArrayList<Object> ads = new ArrayList<>();
ads.add(new Sponsored("Craft Beer 20% Off", "Budweiser"));
ads.add(new Sponsored("Craft Beer 20% Off", "Budweiser"));
ads.add(new Sponsored("Craft Beer 20% Off", "Budweiser"));
ads.add(new Sponsored("Craft Beer 20% Off", "Budweiser"));
return ads;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
bindDataToAdapter(recyclerView);
}
private void bindDataToAdapter(RecyclerView recyclerView) {
recyclerView.setAdapter(new HeterogeneousRecyclerAdapter(getPresidentsArrayList(), getAdsArrayList()));
}
}
My recycler adapter allowing for multiple views:
public class HeterogeneousRecyclerAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private List<Object> items;
private List<Object> ads;
private final int PRESIDENT = 0, SPONSORED = 1;
public HeterogeneousRecyclerAdapter(List<Object> items, List<Object> ads) {
this.items = items;
this.ads = ads;
}
#Override
public int getItemCount() {
return (this.items.size() + this.ads.size());
}
#Override
public int getItemViewType(int position) {
if (items.get(position) instanceof President) {
return PRESIDENT;
} else if (ads.get(position) instanceof Sponsored) {
return SPONSORED;
}
return -1;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
RecyclerView.ViewHolder viewHolder;
LayoutInflater inflater = LayoutInflater.from(viewGroup.getContext());
switch (viewType) {
case PRESIDENT:
View v1 = inflater.inflate(R.layout.layout_viewholder1, viewGroup, false);
viewHolder = new ViewHolder1(v1);
break;
case SPONSORED:
View v2 = inflater.inflate(R.layout.layout_viewholder2, viewGroup, false);
viewHolder = new ViewHolder2(v2);
break;
default:
View v = inflater.inflate(android.R.layout.simple_list_item_1, viewGroup, false);
viewHolder = new RecyclerViewSimpleTextViewHolder(v);
break;
}
return viewHolder;
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int position) {
switch (viewHolder.getItemViewType()) {
case PRESIDENT:
ViewHolder1 vh1 = (ViewHolder1) viewHolder;
configureViewHolder1(vh1, position);
break;
case SPONSORED:
ViewHolder2 vh2 = (ViewHolder2) viewHolder;
configureViewHolder2(vh2, position);
break;
default:
RecyclerViewSimpleTextViewHolder vh = (RecyclerViewSimpleTextViewHolder) viewHolder;
configureDefaultViewHolder(vh, position);
break;
}
}
private void configureDefaultViewHolder(RecyclerViewSimpleTextViewHolder vh, int position) {
vh.getLabel().setText((CharSequence) items.get(position));
}
private void configureViewHolder1(ViewHolder1 vh1, int position) {
President president = (President) items.get(position);
if (president != null) {
vh1.getLabel1().setText(president.getName());
vh1.getLabel2().setText(president.getHometown());
}
}
private void configureViewHolder2(ViewHolder2 vh2, int position) {
Sponsored sponsored = (Sponsored) ads.get(position);
if (sponsored != null) {
vh2.getLabel1().setText(sponsored.getName());
vh2.getLabel2().setText(sponsored.getCompany());
}
}
}

You need to create a common list adding both your list. Just do the following -
public HeterogeneousRecyclerAdapter(List<Object> items, List<Object> ads) {
this.items = items;
items.addAll(ads);
}
Now change the get Item count -
#Override
public int getItemCount() {
return this.items.size();
}
Hope it will work fine for you :)

The implementation of your getItemCount is wrong
#Override
public int getItemCount() {
return (this.items.size() + this.ads.size());
}
if both are not returning 0, you are returning a value that is greater than the size of both collections. That's why you are getting an ArrayIndexOutBoundException. Remember that position goes from 0 to getItemCount - 1 and, in your case, neither items nor ads contain getItemCount objects

The implementation of your getItemViewType is wrong. Lets assume your items List has 4 items and ads has 3 advertisement objects. Now your getItemViewType will return 7. Now system will start to find the item type of these 7 objects . Lets assume it wants to find the type of 5th row in RecyclerView . So now in your method getItemViewType line number 1 itself throw this exception because size of items List is 4 only.
Either you will have to combine these two Lists in single List or have some order among recycler view items, like all the advertisements will appear before items. In that case also you will have to modify your getItemViewType.
Hope this helps.

How to add separator at particular position inside recyclerview?

I have a list of taskLists. To show the list I have used recyclerview. I have 1st 3 items as today , tomorrow and later in my list. I want to add one separator after 1st 3 items in recycler view. How can I do this?
Adapter :
public class ListAdapter extends RecyclerView.Adapter<ListAdapter.ItemViewHolder>{
ArrayList<ListData> item;
public static final int TYPE1=1;
Context conext;
public ListAdapter(Context context, ArrayList<ListData> item) {
this.conext=context;
this.item=item;
}
public interface OnItemClickListener {
void onItemClick(ListData listData);
}
#Override
public int getItemCount() {
return item.size();
}
public void remove(int position) {
item.remove(position);
notifyItemRemoved(position);
}
// #Override
// public int getItemViewType(int position) {
// return item.get(position).getExpenseType();// Assume that this return 1 0r 2
// }
#Override
public void onBindViewHolder(ItemViewHolder itemViewHolder,final int i) {
itemViewHolder.listName.setText(item.get(i).getTitle());
}
#Override
public ItemViewHolder onCreateViewHolder(ViewGroup viewGroup,int viewType) {
View itemView = LayoutInflater.
from(viewGroup.getContext()).
inflate(R.layout.list_layout, viewGroup, false);
return new ItemViewHolder(itemView,viewType);
}
public static class ItemViewHolder extends RecyclerView.ViewHolder {
TextView listName;
ItemViewHolder(View itemView, int viewType) {
super(itemView);
listName = (TextView)itemView.findViewById(R.id.listData);
}
}
#Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
}
}
Can anyone help with this how can I put separator after 3 items in list?
Thank you..

You should define 2 types of RecyclerView rows:
...YourRecyclerAdapter extends RecyclerView.Adapter<BaseViewHolder>
public static final int COMMON = 1;
public static final int SEPARATOR = 2;
Override getItemViewType method of your Adapter:
#Override
public int getItemViewType(int position) {
if (position%10 == 0) //each 10 row is separator (change it!)
return SEPARATOR;
else return COMMON;
}
Change onCreateViewHolder method of your Adapter:
#Override
public BaseViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == COMMON)
return new ItemViewHolder(LayoutInflater.from(activity).inflate(R.layout.list_layout, parent, false));
else
return new SeparatorHolder(LayoutInflater.from(activity).inflate(R.layout.separator_item, parent, false));
}
#Override
public void onBindViewHolder(BaseViewHolder holder, int position) {
if (getItemViewType(position) == COMMON) {
//do stuff
} else {
}
}
ItemViewHolder extends BaseViewHolder
SeparatorHolder extends BaseViewHolder
BaseViewHolder extends RecyclerView.ViewHolder

One solution is define 2 types of RecyclerView rows (one for normal row and one for separator)
Another solution is you should a Separator View in the bottom of your custom RecycleView row xml
<View
android:id="#+id/separatorView"
android:layout_width="match_parent"
android:layout_height="3dp"
android:visible="gone"
android:background="#android:color/darker_gray"/>
Then in bindViewHolder of your RecyclerView.Adapter, hide the separator in normal row and visible it in separator row
#Override
public void bindViewHolder(ViewHolder holder, int position) {
if(position == separatorPosition){
holder.separatorView.visible = View.VISIBLE;
}else{
holder.separatorView.visible = View.GONE;
}
}
Hope this help

You can create two ViewHolder class and Switch them in onCreateViewHolder. One containing your custom line, and others as your custom list items.
class ViewHolderLine extends RecyclerView.ViewHolder { //contains line
}
class ViewHolderItems extends RecyclerView.ViewHolder { //contains data
}
#Override
public int getItemViewType(int position) {
return item.get(position).getExpenseType();// Assume that this return 1 0r 2
}
#Override
public ItemViewHolder onCreateViewHolder(ViewGroup viewGroup,int viewType) {
switch (viewType) {
case 1: return new ViewHolderLine();
case 2:
View itemView = LayoutInflater.
from(viewGroup.getContext()).
inflate(R.layout.list_layout, viewGroup, false);
return new ItemViewHolder(itemView,viewType);
}
}
You can see the details description here for more info.

if you know that you are only going to add separator in the 1st three items, then you can put a condition based on the position of the item, inside onBindViewHolder.
ps: Please do not forget to add an else block after an if block

I have a recyclerview with section header and variable number of items in each section. The section should have a line separator across entire screen. and items must have a padded line between them.
So, my solution(in kotlin) was having two viewholders, one for header and one for item. in getItemViewType, return the type based on the item.
override fun getItemViewType(position: Int): Int {
if(dataList[position] is HeaderItem)
return Companion.TYPE_HEADER
return Companion.TYPE_ITEM
}
and create the corresponding viewholder in createviewholder, bind accordingly.
Used
parent.getChildViewHolder(parent.getChildAt(i))
to decide the padding(or color or width) for the item separator.
class ItemDivider(context: Context) : RecyclerView.ItemDecoration() {
private var mDivider: Drawable
private val mContext = context
companion object {
private val ATTRS = intArrayOf(android.R.attr.listDivider)
}
init {
val styledAttributes = context.obtainStyledAttributes(ATTRS)
mDivider = styledAttributes.getDrawable(0)
mDivider.setTint(ContextCompat.getColor(mContext, <color>))
styledAttributes.recycle()
}
override fun onDraw(c: Canvas, parent: RecyclerView, state: RecyclerView.State?) {
val right = parent.width - parent.paddingRight
for (i in 0 until parent.childCount - 1) {
val child = parent.getChildAt(i)
val params = child.layoutParams as RecyclerView.LayoutParams
val left = if (parent.getChildViewHolder(child) is HeaderViewHolder) {
0
} else {
child.left + params.leftMargin + mContext.resources.getDimension(<padding_in_dp>).toInt()
}
val top = child.bottom + params.bottomMargin
val bottom = top + mDivider.intrinsicHeight + <divider_height>
mDivider.setBounds(left, top, right, bottom)
mDivider.draw(c)
}
}
}
remember to replace the color, padding, divider height with valid values.
Hope it helps!