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Why doesn't RecyclerView have onItemClickListener()?

I was exploring RecyclerView and I was surprised to see that RecyclerView does not have onItemClickListener().

I've two question.

Main Question

I want to know why Google removed onItemClickListener()?

Is there a performance issue or something else?

Secondary Question

I solved my problem by writing onClick in my RecyclerView.Adapter:

public static class ViewHolder extends RecyclerView.ViewHolder implements OnClickListener {

    public TextView txtViewTitle;
    public ImageView imgViewIcon;

    public ViewHolder(View itemLayoutView) {
        super(itemLayoutView);
        txtViewTitle = (TextView) itemLayoutView.findViewById(R.id.item_title);
        imgViewIcon = (ImageView) itemLayoutView.findViewById(R.id.item_icon);
    }

    @Override
    public void onClick(View v) {

    }
}

Is this ok / is there any better way?

For your code to work you need to add itemLayoutView.setOnClickListener(this); in the ViewHolder constructor.
you asked nice question... many developers have same doubt about RecyclerView and ListView.
Question: Why RecyclerView doesnot have OnItemClickListner() ? All answers below except 2 : How to add onclick for RecyclerView
Wish someone actually took out the time to answer the QUESTION
I think they removed it because of performance and garbage memory issues. But look on the accepted answer.... it will produce same problems. I think you made mistake by accepting it and now other ppls do mistakes because of you :).

M
Maragues

tl;dr 2016 Use RxJava and a PublishSubject to expose an Observable for the clicks.

public class ReactiveAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    String[] mDataset = { "Data", "In", "Adapter" };

    private final PublishSubject<String> onClickSubject = PublishSubject.create();

    @Override 
    public void onBindViewHolder(final ViewHolder holder, int position) {
        final String element = mDataset[position];

        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
               onClickSubject.onNext(element);
            }
        });
    }

    public Observable<String> getPositionClicks(){
        return onClickSubject.asObservable();
    }
}

Original Post:

Since the introduction of ListView, onItemClickListener has been problematic. The moment you have a click listener for any of the internal elements the callback would not be triggered but it wasn't notified or well documented (if at all) so there was a lot of confusion and SO questions about it.

Given that RecyclerView takes it a step further and doesn't have a concept of a row/column, but rather an arbitrarily laid out amount of children, they have delegated the onClick to each one of them, or to programmer implementation.

Think of Recyclerview not as a ListView 1:1 replacement but rather as a more flexible component for complex use cases. And as you say, your solution is what google expected of you. Now you have an adapter who can delegate onClick to an interface passed on the constructor, which is the correct pattern for both ListView and Recyclerview.

public static class ViewHolder extends RecyclerView.ViewHolder implements OnClickListener {

    public TextView txtViewTitle;
    public ImageView imgViewIcon;
    public IMyViewHolderClicks mListener;

    public ViewHolder(View itemLayoutView, IMyViewHolderClicks listener) {
        super(itemLayoutView);
        mListener = listener;
        txtViewTitle = (TextView) itemLayoutView.findViewById(R.id.item_title);
        imgViewIcon = (ImageView) itemLayoutView.findViewById(R.id.item_icon);
        imgViewIcon.setOnClickListener(this);
        itemLayoutView.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        if (v instanceof ImageView){
           mListener.onTomato((ImageView)v);
        } else {
           mListener.onPotato(v);
        }
    }

    public static interface IMyViewHolderClicks {
        public void onPotato(View caller);
        public void onTomato(ImageView callerImage);
    }

}

and then on your adapter

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {

   String[] mDataset = { "Data" };

   @Override
   public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
       View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.my_layout, parent, false);

       MyAdapter.ViewHolder vh = new ViewHolder(v, new MyAdapter.ViewHolder.IMyViewHolderClicks() { 
           public void onPotato(View caller) { Log.d("VEGETABLES", "Poh-tah-tos"); };
           public void onTomato(ImageView callerImage) { Log.d("VEGETABLES", "To-m8-tohs"); }
        });
        return vh;
    }

    // Replace the contents of a view (invoked by the layout manager) 
    @Override 
    public void onBindViewHolder(ViewHolder holder, int position) {
        // Get element from your dataset at this position 
        // Replace the contents of the view with that element 
        // Clear the ones that won't be used
        holder.txtViewTitle.setText(mDataset[position]);
    } 

    // Return the size of your dataset (invoked by the layout manager) 
    @Override 
    public int getItemCount() { 
        return mDataset.length;
    } 
  ...

Now look into that last piece of code: onCreateViewHolder(ViewGroup parent, int viewType) the signature already suggest different view types. For each one of them you'll require a different viewholder too, and subsequently each one of them can have a different set of clicks. Or you can just create a generic viewholder that takes any view and one onClickListener and applies accordingly. Or delegate up one level to the orchestrator so several fragments/activities have the same list with different click behaviour. Again, all flexibility is on your side.

It is a really needed component and fairly close to what our internal implementations and improvements to ListView were until now. It's good that Google finally acknowledges it.


RecyclerView.ViewHolder has a getPosition() method. With some adjustments to this code, you can pass the position to the listener.
He completely missed the onBindViewHolder(holder, position) , which is where the info is supposed to be filled.
@se_bastiaan getPosition() is deprecated "This method is deprecated because its meaning is ambiguous due to the async * handling of adapter updates. Please use {@link #getLayoutPosition()} or * {@link #getAdapterPosition()} depending on your use case."
You have several options. Putting the position in an int field inside the viewholder, update it while binding, then returning it on click is one.
@MLProgrammer-CiM "You have several options. Putting the position in an int field inside the viewholder, update it while binding, then returning it on click is one." The ViewHolder already has this value, and is already set. Just call viewHolder.getPosition();
D
Daniele Segato

Why the RecyclerView has no onItemClickListener

The RecyclerView is a toolbox, in contrast of the old ListView it has less build in features and more flexibility. The onItemClickListener is not the only feature being removed from ListView. But it has lot of listeners and method to extend it to your liking, it's far more powerful in the right hands ;).

In my opinion the most complex feature removed in RecyclerView is the Fast Scroll. Most of the other features can be easily re-implemented.

If you want to know what other cool features RecyclerView added read this answer to another question.

Memory efficient - drop-in solution for onItemClickListener

This solution has been proposed by Hugo Visser, an Android GDE, right after RecyclerView was released. He made a licence-free class available for you to just drop in your code and use it.

It showcase some of the versatility introduced with RecyclerView by making use of RecyclerView.OnChildAttachStateChangeListener.

Edit 2019: kotlin version by me, java one, from Hugo Visser, kept below

Kotlin / Java

Create a file values/ids.xml and put this in it:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <item name="item_click_support" type="id" />
</resources>

then add the code below to your source

Kotlin

Usage:

recyclerView.onItemClick { recyclerView, position, v ->
    // do it
}

(it also support long item click and see below for another feature I've added).

implementation (my adaptation to Hugo Visser Java code):

typealias OnRecyclerViewItemClickListener = (recyclerView: RecyclerView, position: Int, v: View) -> Unit
typealias OnRecyclerViewItemLongClickListener = (recyclerView: RecyclerView, position: Int, v: View) -> Boolean

class ItemClickSupport private constructor(private val recyclerView: RecyclerView) {

    private var onItemClickListener: OnRecyclerViewItemClickListener? = null
    private var onItemLongClickListener: OnRecyclerViewItemLongClickListener? = null

    private val attachListener: RecyclerView.OnChildAttachStateChangeListener = object : RecyclerView.OnChildAttachStateChangeListener {
        override fun onChildViewAttachedToWindow(view: View) {
            // every time a new child view is attached add click listeners to it
            val holder = this@ItemClickSupport.recyclerView.getChildViewHolder(view)
                    .takeIf { it is ItemClickSupportViewHolder } as? ItemClickSupportViewHolder

            if (onItemClickListener != null && holder?.isClickable != false) {
                view.setOnClickListener(onClickListener)
            }
            if (onItemLongClickListener != null && holder?.isLongClickable != false) {
                view.setOnLongClickListener(onLongClickListener)
            }
        }

        override fun onChildViewDetachedFromWindow(view: View) {

        }
    }

    init {
        // the ID must be declared in XML, used to avoid
        // replacing the ItemClickSupport without removing
        // the old one from the RecyclerView
        this.recyclerView.setTag(R.id.item_click_support, this)
        this.recyclerView.addOnChildAttachStateChangeListener(attachListener)
    }

    companion object {
        fun addTo(view: RecyclerView): ItemClickSupport {
            // if there's already an ItemClickSupport attached
            // to this RecyclerView do not replace it, use it
            var support: ItemClickSupport? = view.getTag(R.id.item_click_support) as? ItemClickSupport
            if (support == null) {
                support = ItemClickSupport(view)
            }
            return support
        }

        fun removeFrom(view: RecyclerView): ItemClickSupport? {
            val support = view.getTag(R.id.item_click_support) as? ItemClickSupport
            support?.detach(view)
            return support
        }
    }

    private val onClickListener = View.OnClickListener { v ->
        val listener = onItemClickListener ?: return@OnClickListener
        // ask the RecyclerView for the viewHolder of this view.
        // then use it to get the position for the adapter
        val holder = this.recyclerView.getChildViewHolder(v)
        listener.invoke(this.recyclerView, holder.adapterPosition, v)
    }

    private val onLongClickListener = View.OnLongClickListener { v ->
        val listener = onItemLongClickListener ?: return@OnLongClickListener false
        val holder = this.recyclerView.getChildViewHolder(v)
        return@OnLongClickListener listener.invoke(this.recyclerView, holder.adapterPosition, v)
    }

    private fun detach(view: RecyclerView) {
        view.removeOnChildAttachStateChangeListener(attachListener)
        view.setTag(R.id.item_click_support, null)
    }

    fun onItemClick(listener: OnRecyclerViewItemClickListener?): ItemClickSupport {
        onItemClickListener = listener
        return this
    }

    fun onItemLongClick(listener: OnRecyclerViewItemLongClickListener?): ItemClickSupport {
        onItemLongClickListener = listener
        return this
    }

}

/** Give click-ability and long-click-ability control to the ViewHolder */
interface ItemClickSupportViewHolder {
    val isClickable: Boolean get() = true
    val isLongClickable: Boolean get() = true
}

// Extension function
fun RecyclerView.addItemClickSupport(configuration: ItemClickSupport.() -> Unit = {}) = ItemClickSupport.addTo(this).apply(configuration)

fun RecyclerView.removeItemClickSupport() = ItemClickSupport.removeFrom(this)

fun RecyclerView.onItemClick(onClick: OnRecyclerViewItemClickListener) {
    addItemClickSupport { onItemClick(onClick) }
}
fun RecyclerView.onItemLongClick(onLongClick: OnRecyclerViewItemLongClickListener) {
    addItemClickSupport { onItemLongClick(onLongClick) }
}

(Remember you also need to add an XML file, see above this section)

Bonus feature of Kotlin version

Sometimes you do not want all the items of the RecyclerView to be clickable.

To handle this I've introduced the ItemClickSupportViewHolder interface that you can use on your ViewHolder to control which item is clickable.

Example:

class MyViewHolder(view): RecyclerView.ViewHolder(view), ItemClickSupportViewHolder {
    override val isClickable: Boolean get() = false
    override val isLongClickable: Boolean get() = false
}

Java

Usage:

ItemClickSupport.addTo(mRecyclerView)
        .setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
    @Override
    public void onItemClicked(RecyclerView recyclerView, int position, View v) {
        // do it
    }
});

(it also support long item click)

Implementation (comments added by me):

public class ItemClickSupport {
    private final RecyclerView mRecyclerView;
    private OnItemClickListener mOnItemClickListener;
    private OnItemLongClickListener mOnItemLongClickListener;
    private View.OnClickListener mOnClickListener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (mOnItemClickListener != null) {
                // ask the RecyclerView for the viewHolder of this view.
                // then use it to get the position for the adapter
                RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
                mOnItemClickListener.onItemClicked(mRecyclerView, holder.getAdapterPosition(), v);
            }
        }
    };
    private View.OnLongClickListener mOnLongClickListener = new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View v) {
            if (mOnItemLongClickListener != null) {
                RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
                return mOnItemLongClickListener.onItemLongClicked(mRecyclerView, holder.getAdapterPosition(), v);
            }
            return false;
        }
    };
    private RecyclerView.OnChildAttachStateChangeListener mAttachListener
            = new RecyclerView.OnChildAttachStateChangeListener() {
        @Override
        public void onChildViewAttachedToWindow(View view) {
            // every time a new child view is attached add click listeners to it
            if (mOnItemClickListener != null) {
                view.setOnClickListener(mOnClickListener);
            }
            if (mOnItemLongClickListener != null) {
                view.setOnLongClickListener(mOnLongClickListener);
            }
        }

        @Override
        public void onChildViewDetachedFromWindow(View view) {

        }
    };

    private ItemClickSupport(RecyclerView recyclerView) {
        mRecyclerView = recyclerView;
        // the ID must be declared in XML, used to avoid
        // replacing the ItemClickSupport without removing
        // the old one from the RecyclerView
        mRecyclerView.setTag(R.id.item_click_support, this);
        mRecyclerView.addOnChildAttachStateChangeListener(mAttachListener);
    }

    public static ItemClickSupport addTo(RecyclerView view) {
        // if there's already an ItemClickSupport attached
        // to this RecyclerView do not replace it, use it
        ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
        if (support == null) {
            support = new ItemClickSupport(view);
        }
        return support;
    }

    public static ItemClickSupport removeFrom(RecyclerView view) {
        ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
        if (support != null) {
            support.detach(view);
        }
        return support;
    }

    public ItemClickSupport setOnItemClickListener(OnItemClickListener listener) {
        mOnItemClickListener = listener;
        return this;
    }

    public ItemClickSupport setOnItemLongClickListener(OnItemLongClickListener listener) {
        mOnItemLongClickListener = listener;
        return this;
    }

    private void detach(RecyclerView view) {
        view.removeOnChildAttachStateChangeListener(mAttachListener);
        view.setTag(R.id.item_click_support, null);
    }

    public interface OnItemClickListener {

        void onItemClicked(RecyclerView recyclerView, int position, View v);
    }

    public interface OnItemLongClickListener {

        boolean onItemLongClicked(RecyclerView recyclerView, int position, View v);
    }
}

How it works (why it's efficient)

This class works by attaching a RecyclerView.OnChildAttachStateChangeListener to the RecyclerView. This listener is notified every time a child is attached or detached from the RecyclerView. The code use this to append a tap/long click listener to the view. That listener ask the RecyclerView for the RecyclerView.ViewHolder which contains the position.

This is more efficient then other solutions because it avoid creating multiple listeners for each view and keep destroying and creating them while the RecyclerView is being scrolled.

You could also adapt the code to give you back the holder itself if you need more.

Final remark

Keep in mind that it's COMPLETELY fine to handle it in your adapter by setting on each view of your list a click listener, like other answer proposed.

It's just not the most efficient thing to do (you create a new listener every time you reuse a view) but it works and in most cases it's not an issue.

It is also a bit against separation of concerns cause it's not really the Job of the Adapter to delegate click events.


addOnChildAttachStateChangeListener in the constructor and never removing it?
@Saba you aren't supposed to use the constructor directly but through static methods addTo() and removeFrom(). The instance is associated to the recyclerview tag and dies with it or when it's manually removed.
So much code when all you'd need to do is set an on click listener in onCreateViewHolder and that's it.
Your argument is flowed, it's not about the quantity of code but efficiency and responsibility principle and the quantity of code is not a great indication of good/bad solution, specially when that code is reusable and efficient. Once you have put that code in your project (which you can consider as a library inclusion) all you need is a 1-liner on your RecyclerView.
@DanieleSegato Thank you so much for this!
v
vishal dharankar

I like this way and I'm using it

Inside

public Adapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)

Put

View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.view_image_and_text, parent, false);
v.setOnClickListener(new MyOnClickListener());

And create this class anywhere you want it

class MyOnClickListener implements View.OnClickListener {
    @Override
    public void onClick(View v) {
       int itemPosition = recyclerView.indexOfChild(v);
       Log.e("Clicked and Position is ",String.valueOf(itemPosition));
    }
}

I've read before that there is a better way but I like this way is easy and not complicated.


should probably make MyOnClickListener into instance variable, because you'll be creating a new instance of it everytime with the new Keyword
recyclerView.getChildPosition(v); is depricated now use recyclerView. indexOfChild(v);
Don't you have issues when scrolling? On my tests the itemPosition seems to depend on views recycling, so it goes wrong compared to my full list in the adapter.
How to get recyclerView in MyOnClickListener?
Instead of using: int itemPosition = recyclerView.indexOfChild(v); you should use: RecyclerView.ViewHolder holder = recyclerView.getChildViewHolder(v); int itemPosition = holder.getAdapterPosition();
C
ColdFire

Android Recyclerview With onItemClickListener, Why we cant try this is working like ListView only.

Source : Link

public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener {

private OnItemClickListener mListener;
public interface OnItemClickListener {
    public void onItemClick(View view, int position);
}
GestureDetector mGestureDetector;
public RecyclerItemClickListener(Context context, OnItemClickListener listener) {
    mListener = listener;
    mGestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
        @Override
        public boolean onSingleTapUp(MotionEvent e) {
            return true;
        }
    });
}
@Override
public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
    View childView = view.findChildViewUnder(e.getX(), e.getY());
    if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
        mListener.onItemClick(childView, view.getChildAdapterPosition(childView));
    }
    return false;
}

@Override
public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) {
}

@Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

  }
}

And Set this to RecyclerView:

    recyclerView = (RecyclerView)rootView. findViewById(R.id.recyclerView);
    RecyclerView.LayoutManager mLayoutManager = new            LinearLayoutManager(getActivity());
    recyclerView.setLayoutManager(mLayoutManager);
    recyclerView.addOnItemTouchListener(
            new RecyclerItemClickListener(getActivity(), new   RecyclerItemClickListener.OnItemClickListener() {
                @Override
                public void onItemClick(View view, int position) {
                    // TODO Handle item click
                    Log.e("@@@@@",""+position);
                }
            })
    );

No elegant to be honest.
@vishaldharankar why not? I think that it's the best way to avoid conflict of focus change after using SwipeRefreshLayout
This is entirely unnecessary, you can use a View.OnClickListener instead of intercepting touch.
S
Shayan_Aryan

Thanks to @marmor, I updated my answer.

I think it's a good solution to handle the onClick() in the ViewHolder class constructor and pass it to the parent class via OnItemClickListener interface.

MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder>{

private LayoutInflater layoutInflater;
private List<MyObject> items;
private AdapterView.OnItemClickListener onItemClickListener;

public MyAdapter(Context context, AdapterView.OnItemClickListener onItemClickListener, List<MyObject> items) {
    layoutInflater = LayoutInflater.from(context);
    this.items = items;
    this.onItemClickListener = onItemClickListener;
}

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = layoutInflater.inflate(R.layout.my_row_layout, parent, false);
    return new ViewHolder(view);
}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    MyObject item = items.get(position);
}

public MyObject getItem(int position) {
    return items.get(position);
}


class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    private TextView title;
    private ImageView avatar;

    public ViewHolder(View itemView) {
        super(itemView);
        title = itemView.findViewById(R.id.title);
        avatar = itemView.findViewById(R.id.avatar);

        title.setOnClickListener(this);
        avatar.setOnClickListener(this);
        itemView.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        //passing the clicked position to the parent class
        onItemClickListener.onItemClick(null, view, getAdapterPosition(), view.getId());
    }
}
}

Usage of adapter in other classes:

MyFragment.java

public class MyFragment extends Fragment implements AdapterView.OnItemClickListener {

private RecyclerView recycleview;
private MyAdapter adapter;

    .
    .
    .

private void init(Context context) {
    //passing this fragment as OnItemClickListener to the adapter
    adapter = new MyAdapter(context, this, items);
    recycleview.setAdapter(adapter);
}

@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    //you can get the clicked item from the adapter using its position
    MyObject item = adapter.getItem(position);

    //you can also find out which view was clicked
    switch (view.getId()) {
        case R.id.title:
            //title view was clicked
            break;
        case R.id.avatar:
            //avatar view was clicked
            break;
        default:
            //the whole row was clicked
    }
}

}

This will create and garbage-collect tons of objects when scrolling, you should instead create one OnClickListener and re-use it
Also onBindViewHolder() is called many times for the same view when scrolling. Even creating a single OnClickListener will not help because you will be resetting the OnClickListener every time onBindViewHolder() is called. See instead @MLProgrammer-CiM solution.
You can also improve @MLProgrammer-CiM solution and instead of creating a listener object for every View in this line MyAdapter.ViewHolder vh = new ViewHolder(v, new MyAdapter.ViewHolder.IMyViewHolderClicks() .... you can create a single listener for all views.
w
waqas ali

Guys use this code in Your main activity. Very Efficient Method

RecyclerView recyclerView = (RecyclerView) findViewById(R.id.users_list);            
UsersAdapter adapter = new UsersAdapter(users, this);
recyclerView.setAdapter(adapter);
adapter.setOnCardClickListner(this);

Here is your Adapter class.

public class UsersAdapter extends RecyclerView.Adapter<UsersAdapter.UserViewHolder> {
        private ArrayList<User> mDataSet;
        OnCardClickListner onCardClickListner;


        public UsersAdapter(ArrayList<User> mDataSet) {
            this.mDataSet = mDataSet;
        }

        @Override
        public UserViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.user_row_layout, parent, false);
            UserViewHolder userViewHolder = new UserViewHolder(v);
            return userViewHolder;
        }

        @Override
        public void onBindViewHolder(UserViewHolder holder, final int position) {
            holder.name_entry.setText(mDataSet.get(position).getUser_name());
            holder.cardView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    onCardClickListner.OnCardClicked(v, position);
                }
            });
        }

        @Override
        public int getItemCount() {
            return mDataSet.size();
        }

        @Override
        public void onAttachedToRecyclerView(RecyclerView recyclerView) {
            super.onAttachedToRecyclerView(recyclerView);
        }


        public static class UserViewHolder extends RecyclerView.ViewHolder {
            CardView cardView;
            TextView name_entry;

            public UserViewHolder(View itemView) {
                super(itemView);
                cardView = (CardView) itemView.findViewById(R.id.user_layout);
                name_entry = (TextView) itemView.findViewById(R.id.name_entry);
             }
        }

        public interface OnCardClickListner {
            void OnCardClicked(View view, int position);
        }

        public void setOnCardClickListner(OnCardClickListner onCardClickListner) {
            this.onCardClickListner = onCardClickListner;
        }
    }

After this you will get this override method in your activity.

@Override
    public void OnCardClicked(View view, int position) {
        Log.d("OnClick", "Card Position" + position);
    }

I wonder if user scrolling up & down, OnClickListener will create & be recycle over & over again, it it efficiently?
To get the updated position of card, this minor thing can be compromised.
hi friend nice its working charm,i have a requirement activity with categories and products initially,if user select category icon i need to display categories in dialog box or activity if user select any category based thata load filtered data on to first activity please help me how to solve
1st: You need to add a method named OnProductClicked in interface OnCardClickListner like this public interface OnCardClickListner { void OnCardClicked(View view, int position); void OnProductClicked (View view, int position); } 2nd: Then implement click listener on your product icon like this. holder.yourProductIcon.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { onCardClickListner.OnProductClicked (v, position); } });
I am unable to Override OnCardClicked. How are folks upvoting this answer?
Z
Ziem

> How RecyclerView is different from Listview?

One difference is that there is LayoutManager class with RecyclerView by which you can manage your RecyclerView like-

Horizontal or Vertical scrolling by LinearLayoutManager GridLayout by GridLayoutManager Staggered GridLayout by StaggeredGridLayoutManager

Like for horizontal scrolling for RecyclerView-

LinearLayoutManager llm = new LinearLayoutManager(context);
llm.setOrientation(LinearLayoutManager.HORIZONTAL);
recyclerView.setLayoutManager(llm);

C
Community

How to put it all together example...

onClick() handling

Cursor - RecyclerView

ViewHolder types public class OrderListCursorAdapter extends CursorRecyclerViewAdapter { private static final String TAG = OrderListCursorAdapter.class.getSimpleName(); private static final int ID_VIEW_HOLDER_ACTUAL = 0; private static final int ID_VIEW_HOLDER = 1; public OrderListCursorAdapter(Context context, Cursor cursor) { super(context, cursor); } public static class ViewHolderActual extends ViewHolder { private static final String TAG = ViewHolderActual.class.getSimpleName(); protected IViewHolderClick listener; protected Button button; public ViewHolderActual(View v, IViewHolderClick listener) { super(v, listener); this.listener = listener; button = (Button) v.findViewById(R.id.orderList_item_button); button.setOnClickListener(this); } public void initFromData(OrderData data) { Log.d(TAG, ">>onCreateViewHolder(parent=" + parent + ", viewType=" + viewType + ")"); ViewHolder result; switch (viewType) { case ID_VIEW_HOLDER_ACTUAL: { View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.card_layout_actual, parent, false); result = new ViewHolderActual(itemView, new ViewHolderActual.IViewHolderClick() { @Override public void onCardClick(View view, int position, ViewHolder viewHolder) { Log.d(TAG, ">


H
Hadas Kaminsky

Following up MLProgrammer-CiM's excellent RxJava solution

Consume / Observe clicks

Consumer<String> mClickConsumer = new Consumer<String>() {
        @Override
        public void accept(@NonNull String element) throws Exception {
            Toast.makeText(getApplicationContext(), element +" was clicked", Toast.LENGTH_LONG).show();
        }
    };

ReactiveAdapter rxAdapter = new ReactiveAdapter();
rxAdapter.getPositionClicks().subscribe(mClickConsumer);

RxJava 2.+

Modify the original tl;dr as:

public Observable<String> getPositionClicks(){
    return onClickSubject;
}

PublishSubject#asObservable() was removed. Just return the PublishSubject which is an Observable.


Where are you getting mClickConsumer on second line, if you please explain a little bit. rxAdapter.getPositionClicks().subscribe(mClickConsumer);
Z
ZygD

As far as I understand MLProgrammer-CiM answer, simply it's possible to just do this:

class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
    private ImageView image;
    private TextView title;
    private TextView price;

    public MyViewHolder(View itemView) {
        super(itemView);
        image = (ImageView)itemView.findViewById(R.id.horizontal_list_image);
        title = (TextView)itemView.findViewById(R.id.horizontal_list_title);
        price = (TextView)itemView.findViewById(R.id.horizontal_list_price);
        image.setOnClickListener(this);
        title.setOnClickListener(this);
        price.setOnClickListener(this);
    }


    @Override
    public void onClick(View v) {
        Toast.makeText(context, "Item click nr: "+getLayoutPosition(), Toast.LENGTH_SHORT).show();
    }
}

E
EpicPandaForce

RecyclerView doesn't have an onItemClickListener because RecyclerView is responsible for recycling views (surprise!), so it's the responsibility of the view that is recycled to handle the click events it receives.

This actually makes it much easier to use, especially if you had items that can be clicked in multiple places.

Anyways, detecting click on a RecyclerView item is very easy. All you need to do is define an interface (if you're not using Kotlin, in which case you just pass in a lambda):

public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
    private final Clicks clicks;

    public MyAdapter(Clicks clicks) {
        this.clicks = clicks;
    }

    private List<MyObject> items = Collections.emptyList();

    public void updateData(List<MyObject> items) {
        this.items = items;
        notifyDataSetChanged(); // TODO: use ListAdapter for diffing instead if you need animations
    }

    public interface Clicks {
        void onItemSelected(MyObject myObject, int position);
    }

    public class MyViewHolder extends RecyclerView.ViewHolder {
        private MyObject myObject;    

        public MyViewHolder(View view) {
            super(view);
            // bind views
            view.setOnClickListener((v) -> {
                int adapterPosition = getAdapterPosition();
                if(adapterPosition >= 0) {
                    clicks.onItemSelected(myObject, adapterPosition);
                }
            });
        }

        public void bind(MyObject myObject) {
            this.myObject = myObject;
            // bind data to views
        }
    }
}

Same code in Kotlin:

class MyAdapter(val itemClicks: (MyObject, Int) -> Unit): RecyclerView.Adapter<MyViewHolder>() {
    private var items: List<MyObject> = Collections.emptyList()

    fun updateData(items: List<MyObject>) {
        this.items = items
        notifyDataSetChanged() // TODO: use ListAdapter for diffing instead if you need animations
    }

    inner class MyViewHolder(val myView: View): RecyclerView.ViewHolder(myView) {
        private lateinit var myObject: MyObject

        init {
            // binds views
            myView.onClick {
                val adapterPosition = getAdapterPosition()
                if(adapterPosition >= 0) {
                    itemClicks.invoke(myObject, adapterPosition)
                }
            }
        }

        fun bind(myObject: MyObject) {
            this.myObject = myObject
            // bind data to views
        }
    }
}

Thing you DON'T need to do:

1.) you don't need to intercept touch events manually

2.) you don't need to mess around with child attach state change listeners

3.) you don't need PublishSubject/PublishRelay from RxJava

Just use a click listener.


There is no onClick handling in the video?
Checkout 0:45 in the video there is an onClickListener attached in the adapter
c
chad

After reading @MLProgrammer-CiM's answer, here is my code:

class NormalViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{

    @Bind(R.id.card_item_normal)
    CardView cardView;

    public NormalViewHolder(View itemView) {
        super(itemView);
        ButterKnife.bind(this, itemView);
        cardView.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        if(v instanceof CardView) {
            // use getAdapterPosition() instead of getLayoutPosition()
            int itemPosition = getAdapterPosition();
            removeItem(itemPosition);
        }
    }
}

Beware that getAdapterPosition can return -1 for "no position".
H
Hiren Patel

I have done this way, its very simple:

Just add 1 Line for Clicked RecyclerView position:

int position = getLayoutPosition()

Full code for ViewHolder class:

private class ChildViewHolder extends RecyclerView.ViewHolder {
        public ImageView imageView;
        public TextView txtView;

        public ChildViewHolder(View itemView) {
            super(itemView);
            imageView= (ImageView)itemView.findViewById(R.id.imageView);
            txtView= (TextView) itemView.findViewById(R.id.txtView);
            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Log.i("RecyclerView Item Click Position", String.valueOf(getLayoutPosition()));
                }
            });
        }
    }

Hope this will help you.


You should use getAdapterPosition instead of getLayoutPosition. Guard against -1.
t
tmac12

I use this method to start an Intent from RecyclerView:

@Override
 public void onBindViewHolder(ViewHolder viewHolder, int i) {

    final MyClass myClass = mList.get(i);
    viewHolder.txtViewTitle.setText(myclass.name);
   ...
    viewHolder.itemView.setOnClickListener(new View.OnClickListener() {
      @Override
       public void onClick(View v){
             Intent detailIntent = new Intent(mContext, type.class);                                                            
             detailIntent.putExtra("MyClass", myclass);
             mContext.startActivity(detailIntent);
       }
}
);

It isn't good way. Because onBindViewHolder(...) isn't called after notify() methods. So, you can get wrong click position in some situations.
A
Alexandru Circus

See my approach on this:

First declare an interface like this:

/**
 * Interface used for delegating item click events in a {@link android.support.v7.widget.RecyclerView}
 * Created by Alex on 11/28/2015.
 */
  public interface OnRecyclerItemClickListener<T> {

     /**
      * Called when a click occurred inside a recyclerView item view
      * @param view that was clicked
      * @param position of the clicked view
      * @param item the concrete data that is displayed through the clicked view
      */
      void onItemClick(View view, int position, T item);
   }

Then create the adapter:

public class CustomRecyclerAdapter extends RecyclerView.Adapter {      

    private class InternalClickListener implements View.OnClickListener{

      @Override
      public void onClick(View v) {
        if(mRecyclerView != null && mItemClickListener != null){
            // find the position of the item that was clicked
            int position = mRecyclerView.getChildAdapterPosition(v);
            Data data = getItem(position);
            // notify the main listener
            mItemClickListener.onItemClick(v, position, data);
        }
    }
}

private final OnRecyclerItemClickListener mItemClickListener;
private RecyclerView mRecyclerView;    
private InternalClickListener mInternalClickListener;


/**
 *
 * @param itemClickListener used to trigger an item click event
 */
public PlayerListRecyclerAdapter(OnRecyclerItemClickListener itemClickListener){        
    mItemClickListener = itemClickListener;
    mInternalClickListener = new InternalClickListener();
}

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
   View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_item, parent, false);

    v.setOnClickListener(mInternalClickListener);

    ViewHolder viewHolder = new ViewHolder(v);
    return viewHolder;
}

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
    // do your binding here
}

@Override
public int getItemCount() {
    return mDataSet.size();
}

@Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
    super.onAttachedToRecyclerView(recyclerView);

    mRecyclerView = recyclerView;
}

@Override
public void onDetachedFromRecyclerView(RecyclerView recyclerView) {
    super.onDetachedFromRecyclerView(recyclerView);

    mRecyclerView = null;
}

public Data getItem(int position){
    return mDataset.get(position);
}
}

And now let's see how to integrate this from a fragment:

public class TestFragment extends Fragment implements OnRecyclerItemClickListener<Data>{
   private RecyclerView mRecyclerView;

   @Override
   public void onItemClick(View view, int position, Data item) {
     // do something
   }

   @Override
   public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
      return inflater.inflate(R.layout.test_fragment, container, false);
   }

   @Override
   public void onViewCreated(View view, Bundle savedInstanceState) {
      mRecyclerView = view.findViewById(idOfTheRecycler);
      mRecyclerView .setAdapter(new CustomRecyclerAdapter(this));
   }

c
cryyyyy

If you want to add onClick() to the child view of items, for example, a button in item, I found that you can do it easily in onCreateViewHolder() of your own RecyclerView.Adapter just like this:

        @Override
        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View v = LayoutInflater
                    .from(parent.getContext())
                    .inflate(R.layout.cell, null);

            Button btn = (Button) v.findViewById(R.id.btn);
            btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    //do it
                }
            });

            return new MyViewHolder(v);
        }

i don't know whether it's a good way, but it works well. If anyone has a better idea, very glad to tell me and correct my answer! :)


S
Simon

Here is a way to implement it quite easily if you have a list of POJOs and want to retrieve one on click from outside the adapter.

In your adapter, create a listener for the click events and a method to set it:

public class MyAdapter extends RecyclerView.Adapter<SitesListAdapter.ViewHolder> {
...
private List<MyPojo> mMyPojos;
private static OnItemClickListener mOnItemClickListener;

...
public interface OnItemClickListener {
    public void onItemClick(MyPojo pojo);
}

...
public void setOnItemClickListener(OnItemClickListener onItemClickListener){
    mOnItemClickListener = onItemClickListener;
}
...

}

In your ViewHolder, implement onClickListener and create a class member to temporarily store the POJO the view is presenting, that way (this is an example, creating a setter would be better):

public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    public MyPojo mCurrentPojo;
    ...
    public ViewHolder(View view) {
        super(v);
        ...
        view.setOnClickListener(this); //You could set this on part of the layout too
    }

    ...
    @Override
    public void onClick(View view) {
        if(mOnItemClickListener != null && mCurrentPojo != null){
            mOnItemClickListener.onItemClick(mCurrentPojo);
        }
    }

Back in your adapter, set the current POJO when the ViewHolder is bound (or to null if the current view doesn't have one):

@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
    final MyPojo currentPojo = mMyPojos.get(position); 
    holder.mCurrentPojo = currentPojo;
    ...

That's it, now you can use it like this from your fragment/activity:

    mMyAdapter.setOnItemClickListener(new mMyAdapter.OnItemClickListener() {
        @Override
        public void onItemClick(MyPojo pojo) {
            //Do whatever you want with your pojo here
        }
    });

you are trying to implement Interface as if it would be an Object method. This won't work
Update : What you need is mMyAdapter.setOnItemClickListener(MyAdapter.OnItemClickListener() {});
@Akshay Sorry but I think my code is correct. Did you try it? All the listeners on Android follow the same principle, and you need to instantiate the interface with a 'new' (ex: stackoverflow.com/questions/4709870/…)
Listener should not be static.
N
Nikolay Mihaylov

Yes you can

public ViewHolder onCreateViewHolder(ViewGroup parent,int viewType) {

    //inflate the view 

    View view = LayoutInflator.from(parent.getContext()).inflate(R.layout.layoutID,null);

    ViewHolder holder = new ViewHolder(view);

    //here we can set onClicklistener
    view.setOnClickListener(new  View.OnClickListeener(){
        public void onClick(View v)
        {
            //action
        }
    });

return holder;

N
Naren

This worked for me:

@Override
public void onBindViewHolder(PlacesListViewAdapter.ViewHolder holder, int position) {
    ----
    ----
    ----
    // Set setOnClickListener(holder);
}


@Override
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    ----
    ----
    ----

    @Override
    public void onClick(View view) {
        // Use to get the item clicked getAdapterPosition()
    }
}

It isn't good way setting setOnClickListener(holder) in onBindViewHolder(). Because onBindViewHolder(...) isn't called after notify() methods. So, you can get wrong click position in some situations.
You should create the click listener inside onCreateViewHolder.
A
Arpit Patel

Here you can handle multiple onclick see below code and it is very efficient

    public class RVNewsAdapter extends RecyclerView.Adapter<RVNewsAdapter.FeedHolder> {

    private Context context;
    List<News> newsList;
    // Allows to remember the last item shown on screen
    private int lastPosition = -1;

    public RVNewsAdapter(List<News> newsList, Context context) {
        this.newsList = newsList;
        this.context = context;
    }

    public static class FeedHolder extends RecyclerView.ViewHolder implements OnClickListener {

        ImageView img_main;
        TextView tv_title;
        Button bt_facebook, bt_twitter, bt_share, bt_comment;


        public FeedHolder(View itemView) {
            super(itemView);

            img_main = (ImageView) itemView.findViewById(R.id.img_main);
            tv_title = (TextView) itemView.findViewById(R.id.tv_title);
            bt_facebook = (Button) itemView.findViewById(R.id.bt_facebook);
            bt_twitter = (Button) itemView.findViewById(R.id.bt_twitter);
            bt_share = (Button) itemView.findViewById(R.id.bt_share);
            bt_comment = (Button) itemView.findViewById(R.id.bt_comment);

            img_main.setOnClickListener(this);
            bt_facebook.setOnClickListener(this);
            bt_twitter.setOnClickListener(this);
            bt_comment.setOnClickListener(this);
            bt_share.setOnClickListener(this);

        }


        @Override
        public void onClick(View v) {

            if (v.getId() == bt_comment.getId()) {

                Toast.makeText(v.getContext(), "Comment  " , Toast.LENGTH_SHORT).show();

            } else if (v.getId() == bt_facebook.getId()) {

                Toast.makeText(v.getContext(), "Facebook  " , Toast.LENGTH_SHORT).show();

            } else if (v.getId() == bt_twitter.getId()) {

                Toast.makeText(v.getContext(), "Twitter  " , Toast.LENGTH_SHORT).show();

            } else if (v.getId() == bt_share.getId()) {

                Toast.makeText(v.getContext(), "share  " , Toast.LENGTH_SHORT).show();

            }
            else {
                Toast.makeText(v.getContext(), "ROW PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
            }
        }
    }

    @Override
    public void onAttachedToRecyclerView(RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
    }

    @Override
    public FeedHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.feed_row, parent, false);
        FeedHolder feedHolder = new FeedHolder(view);

        return feedHolder;
    }

    @Override
    public void onBindViewHolder(FeedHolder holder, int position) {

        holder.tv_title.setText(newsList.get(position).getTitle());


        // Here you apply the animation when the view is bound
        setAnimation(holder.img_main, position);
    }

    @Override
    public int getItemCount() {
        return newsList.size();
    }


    /**
     * Here is the key method to apply the animation
     */
    private void setAnimation(View viewToAnimate, int position) {
        // If the bound view wasn't previously displayed on screen, it's animated
        if (position > lastPosition) {
            Animation animation = AnimationUtils.loadAnimation(context, android.R.anim.slide_in_left);
            viewToAnimate.startAnimation(animation);
            lastPosition = position;
        }
    }


}

He meant the itemView.
O
OneCricketeer

Modified my comment...

public class MyViewHolder extends RecyclerView.ViewHolder {

        private Context mContext;

        public MyViewHolder(View itemView) {
            super(itemView);

            mContext = itemView.getContext();

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {

                    int itemPosition = getLayoutPosition();
                    Toast.makeText(mContext, "" + itemPosition, Toast.LENGTH_SHORT).show();

                }
            });
        }

It's a suggestion, but better if you delete this answer, unless many people will vote negatively. This solution is definitively wrong, it works but is bad programming. Please read some blogs for RecyclerView and study some Adapter libraries, there are many valid in Github already, like FlexibleAdapter, FastAdapter and so on...
You answer is relatively new of a long list of high voted answers and at the bottom of the page, that's why it still has 0 votes. By the way, in the new code, you should use getAdapterPosition().
M
Mudassir Khan

Check this one in which I have implemented all the things with a proper way

RecyclerViewHolder Class

public class RecyclerViewHolder extends RecyclerView.ViewHolder  {

    //view holder is for girdview as we used in the listView
    public ImageView imageView,imageView2;
    public RecyclerViewHolder(View itemView) {
        super(itemView);
        this.imageView=(ImageView)itemView.findViewById(R.id.image);
    }

}

Adapter

public class RecyclerView_Adapter extends RecyclerView.Adapter<RecyclerViewHolder> {

    //RecyclerView will extend to recayclerview Adapter
    private ArrayList<ModelClass> arrayList;
    private Context context;
    private static RecyclerViewClickListener itemListener;
    //constructor of the RecyclerView Adapter
    RecyclerView_Adapter(Context context,ArrayList<ModelClass> arrayList,RecyclerViewClickListener itemListener){
        this.context=context;
        this.arrayList=arrayList;
        this.itemListener=itemListener;
    }

    @Override
    public RecyclerViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        //this method will inflate the custom layout and return as viewHolder
        LayoutInflater layoutInflater=LayoutInflater.from(parent.getContext());
        ViewGroup mainGroup=(ViewGroup) layoutInflater.inflate(R.layout.single_item,parent,false);
        RecyclerViewHolder listHolder=new RecyclerViewHolder(mainGroup);

        return listHolder;
    }

    @Override
    public void onBindViewHolder(RecyclerViewHolder holder, final int position) {

        final ModelClass modelClass=arrayList.get(position);
        //holder
        RecyclerViewHolder mainHolder=(RecyclerViewHolder)holder;
        //convert the drawable image into bitmap
        Bitmap image= BitmapFactory.decodeResource(context.getResources(),modelClass.getImage());
        //set the image into imageView
        mainHolder.imageView.setImageBitmap(image);
        //to handle on click event when clicked on the recyclerview item and
        // get it through the RecyclerViewHolder class we have defined the views there
        mainHolder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //get the position of the image which is clicked
             itemListener.recyclerViewListClicked(v,position);
            }
        });

    }

    @Override
    public int getItemCount() {
        return (null!=arrayList?arrayList.size():0);
    }
}

The interface

public interface RecyclerViewClickListener {

    //this is method to handle the event when clicked on the image in Recyclerview
    public void recyclerViewListClicked(View v,int position);
}

//and to call this method in activity
RecyclerView_Adapter adapter=new RecyclerView_Adapter(Wallpaper.this,arrayList,this);
        recyclerView.setAdapter(adapter);
        adapter.notifyDataSetChanged();


    @Override
    public void  recyclerViewListClicked(View v,int position){

        imageView.setImageResource(wallpaperImages[position]);

    }

ρ
ρяσѕρєя K

Access the mainView of rowLayout(cell) for you RecyclerView and in your OnBindViewHolder write this code:

    @Override
    public void onBindViewHolder(MyViewHolder holder, final int position) {
        Movie movie = moviesList.get(position);
        holder.mainView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                System.out.println("pos " + position);
            }
        });
    }

T
That's Enam

it worked for me. Hope it will help. Most simplest way.

Inside View Holder

class GeneralViewHolder extends RecyclerView.ViewHolder {
    View cachedView = null;

    public GeneralViewHolder(View itemView) {
        super(itemView);
        cachedView = itemView;
    }

Inside OnBindViewHolder()

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position) {
            final GeneralViewHolder generalViewHolder = (GeneralViewHolder) holder;
            generalViewHolder.cachedView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Toast.makeText(context, "item Clicked at "+position, Toast.LENGTH_SHORT).show();
                }
            });

And let me know, do you have any question about this solution ?


You should set the onClickListener in onCreateViewHolder for better performance, but then you need to get the position using getAdapterPosition() (and guard against -1)
M
Manikanta

Instead of implementing interface View.OnClickListener inside view holder or creating and interface and implementing interface in your activity.. I used this code for simple on OnClickListener implementation.

public static class SimpleStringRecyclerViewAdapter
            extends RecyclerView.Adapter<SimpleStringRecyclerViewAdapter.ViewHolder> {

        // Your initializations goes here...
        private List<String> mValues;

        public static class ViewHolder extends RecyclerView.ViewHolder {

            //create a variable mView
            public final View mView;

            /*All your row widgets goes here
            public final ImageView mImageView;
            public final TextView mTextView;*/

            public ViewHolder(View view) {
                super(view);
                //Initialize it here
                mView = view;

                /* your row widgets initializations goes here
                mImageView = (ImageView) view.findViewById(R.id.avatar);
                mTextView = (TextView) view.findViewById(android.R.id.text1);*/
            }
        }

        public String getValueAt(int position) {
            return mValues.get(position);
        }

        public SimpleStringRecyclerViewAdapter(Context context, List<String> items) {

            mBackground = mTypedValue.resourceId;
            mValues = items;
        }

        @Override
        public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View view = LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.list_item, parent, false);
            view.setBackgroundResource(mBackground);
            return new ViewHolder(view);
        }

        @Override
        public void onBindViewHolder(final ViewHolder holder, int position) {
            holder.mBoundString = mValues.get(position);
            holder.mTextView.setText(mValues.get(position));

            //Here it is simply write onItemClick listener here
            holder.mView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Context context = v.getContext();
                    Intent intent = new Intent(context, ExampleActivity.class);

                    context.startActivity(intent);
                }
            });
        }

        @Override
        public int getItemCount() {
            return mValues.size();
        }
    }

And you think creating a new OnItemClickListener object at each onBind() method call is a good approach?
Good job. Works great!
R
Roman Marusyk

use PlaceHolderView

@Layout(R.layout.item_view_1)
public class View1{

    @View(R.id.txt)
    public TextView txt;

    @Resolve
    public void onResolved() {
        txt.setText(String.valueOf(System.currentTimeMillis() / 1000));
    }

    @Click(R.id.btn)
    public void onClick(){
        txt.setText(String.valueOf(System.currentTimeMillis() / 1000));
    }
}

I like the solution, it looks neat and perfectly aligned with the Pertusin library I use currently.
d
dileep krishnan
 main_recyclerview.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() {
        @Override
        public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e)
        {
            int position=rv.getChildAdapterPosition(rv.findChildViewUnder(e.getX(),e.getY()));

            switch (position)
            {
                case 0:
                {
                    wifi(position);
                    adapter2.notifyDataSetChanged();
                }
                break;

                case 1:
                {
                    sound(position);
                    adapter2.notifyDataSetChanged();
                }
                break;

                case 2:
                {
                    bluetooth(position);
                    adapter2.notifyDataSetChanged();
                }
                break;


            }
            return true;
        }

        @Override
        public void onTouchEvent(RecyclerView rv, MotionEvent e)
        {

        }

        @Override
        public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {

        }
    });

The question is "Why doesn't RecyclerView have onItemClickListener()?" NOT "How to implement onItemClickListener() in RecyclerView?" .
C
Chathura Jayanath

I wrote a library to handle android recycler view item click event. You can find whole tutorial in https://github.com/ChathuraHettiarachchi/RecycleClick

RecycleClick.addTo(YOUR_RECYCLEVIEW).setOnItemClickListener(new RecycleClick.OnItemClickListener() {
            @Override
            public void onItemClicked(RecyclerView recyclerView, int position, View v) {
                // YOUR CODE
            }
        });

or to handle item long press you can use

RecycleClick.addTo(YOUR_RECYCLEVIEW).setOnItemLongClickListener(new RecycleClick.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClicked(RecyclerView recyclerView, int position, View v) {
                // YOUR CODE
                return true;
            }
        });

Sir i have tried your library but facing issue with maven?
王 能

recyclerview animation has not been tested, the other is normal. I think it has been optimized to the maximum. Interface has other uses, you can temporarily ignore.

public abstract class BaseAdapterRV<VH extends BaseViewHolder> extends RecyclerView.Adapter<VH> implements AdapterInterface {
    public final String TAG = getClass().getSimpleName();

    protected final Activity mActivity;
    protected final LayoutInflater mInflater;
    protected ItemClickInterface<?, Integer> mListener;

    public BaseAdapterRV(Activity activity) {
        mActivity = activity;
        mInflater = LayoutInflater.from(mActivity);
    }

    @Override
    public final VH onCreateViewHolder(ViewGroup parent, int viewType) {
        return onCreateViewHolder(parent, viewType, mInflater);
    }

    @Override
    public final void onBindViewHolder(VH holder, int position) {
        holder.itemView.setTag(R.id.tag_view_click, position);
        //创建点击事件
        holder.itemView.setOnClickListener(mListener);
        holder.itemView.setOnLongClickListener(mListener);
        onBindVH(holder, position);
    }


    ///////////////////////////////////////////////////////////////////////////
    // 以下是增加的方法
    ///////////////////////////////////////////////////////////////////////////

    /**
     * 注意!涉及到notifyItemInserted刷新时立即获取position可能会不正确
     * 里面也有onItemLongClick
     */
    public void setOnItemClickListener(ItemClickInterface<?, Integer> listener) {
        mListener = listener;
        notifyDataSetChanged();
    }

    @NonNull
    protected abstract VH onCreateViewHolder(ViewGroup parent, int viewType, LayoutInflater inflater);

    protected abstract void onBindVH(VH holder, int position);

}

This is Interface

/**
 * OnItemClickListener的接口
 * 见子类实现{@link OnItemClickListener}{@link OnItemItemClickListener}
 */
public interface ItemClickInterface<DATA1, DATA2> extends View.OnClickListener, View.OnLongClickListener {

    void onItemClick(DATA1 data1, DATA2 data2);

    boolean onItemLongClick(DATA1 data1, DATA2 data2);
}

This is an abstract class

public abstract class OnItemClickListener<DATA> implements ItemClickInterface<View, DATA> {
    @Override
    public void onClick(View v) {
        onItemClick(v, (DATA) v.getTag(R.id.tag_view_click));
    }

    @Override
    public boolean onLongClick(View v) {
        return onItemLongClick(v, (DATA) v.getTag(R.id.tag_view_click));
    }

    @Override
    public boolean onItemLongClick(View view, DATA data) {
        return false;
    }
}

You only need it

    mAdapter.setOnItemClickListener(new OnItemClickListener<Integer>() {
        @Override
        public void onItemClick(View view, Integer integer) {

        }

        @Override
        public boolean onItemLongClick(View view, Integer integer) {
            return true;
        }
    });

BaseViewHolder as RecyclerView.ViewHolder
R.id.tag_view_click needs you to declare in the values directory
s
sanevys

I found one of the shortest ways using androidx lifecycle mutable live data

Adapter:

private val onItemClickListener = MutableLiveData<YourAdapterItem>()


override fun onBindViewHolder(holder: GifsViewHolder, position: Int) {
    holder.itemView.setOnClickListener { onItemClickListener.value = gifs[position] }
}
fun getOnItemClickListener(): MutableLiveData<Gif> {
    return onItemClickListener
}

anywhere in MainActivity

    yourFancyAdapter.getOnItemClickListener().observe(this, Observer {
        println(it)
    })