Recyclerview Itemclicklistener in Kotlin

RecyclerView itemClickListener in Kotlin

I have a little bit different approach. You can create an extension for your ViewHolder

fun <T : RecyclerView.ViewHolder> T.listen(event: (position: Int, type: Int) -> Unit): T {
    itemView.setOnClickListener {
        event.invoke(getAdapterPosition(), getItemViewType())
    }
    return this
}

Then use it in adapter like this

class MyAdapter : RecyclerView.Adapter<MyAdapter.MyViewHolder>() {

    val items: MutableList<String> = arrayListOf()

    override fun onCreateViewHolder(parent: ViewGroup?, viewType: Int): MyViewHolder? {
        val inflater = LayoutInflater.from(parent!!.getContext())
        val view = inflater.inflate(R.layout.item_view, parent, false)
        return MyViewHolder(view).listen { pos, type ->
            val item = items.get(pos)
            //TODO do other stuff here
        }
    }

    override fun onBindViewHolder(holder: MyViewHolder?, position: Int) {

    }

    override fun getItemCount(): Int {
        return items.size()
    }

    class MyViewHolder(view: View) : RecyclerView.ViewHolder(view) {

    }
}

I am working with my colleagues on library providing such extensions.

RecyclerView onitemClickListener in Kotlin

Follow below steps:

Step - 1: You have to implements OnChapterClick in your MainActivity2

class MainActivity2: AppCompatActivity, OnChapterClick {
    ....

    override fun onItemClick(list: Model, position: Int ) {

        //Implement your logic here
    } 
}

Step - 2: Change your CustomeAdapter's constructor to accept OnChapterClick instead of int

class CustomeAdapter(val ctx: Context, var clickListener: OnChapterClick, var chapterlist:ArrayList<Model>) : RecyclerView.Adapter<ViewHolder>() {

    ....
}

Step - 3: Initialize the adapter with this instead of R.layout.row like below:

val adapter = CustomeAdapter(applicationContext, this@MainActivity2, chapterlist)

How to add a click listener to my recycler view (Android kotlin)

Try this

 override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
        holder.textViewName.text = seriesList[position].name
        holder.textViewNameDesc.text = seriesList[position].desc

        holder.textViewName.setOnClickListener {
            Toast.makeText(context,"clicked",Toast.LENGTH_SHORT).show()
        }

    }

RecyclerView Item Click Listener the Right Way

You need to check this tutorial here for better understanding on how you can achieve the behaviour that you want.

In case of handling the onClickListener from your activity you need to work based on a callback implementation with an interface. Pass the interface from the activity to your adapter and then call the callback function from your adapter when some items are clicked.

Here's a sample implementation from the tutorial.

Let us first have the interface.

public interface OnItemClickListener {
    void onItemClick(ContentItem item);
}

You need to modify your adapter to take the listener as the parameter like the one stated below.

private final List<ContentItem> items;
private final OnItemClickListener listener;

public ContentAdapter(List<ContentItem> items, OnItemClickListener listener) {
    this.items = items;
    this.listener = listener;
}

Now in your onBindViewHolder method, set the click listener.

@Override public void onBindViewHolder(ViewHolder holder, int position) {
    holder.bind(items.get(position), listener);
}

public void bind(final ContentItem item, final OnItemClickListener listener) {
    ...
    itemView.setOnClickListener(new View.OnClickListener() {
        @Override public void onClick(View v) {
            listener.onItemClick(item);
        }
    });
}

Now setting the adapter in your RecyclerView.

recycler.setAdapter(new ContentAdapter(items, new ContentAdapter.OnItemClickListener() {
    @Override public void onItemClick(ContentItem item) {
        Toast.makeText(getContext(), "Item Clicked", Toast.LENGTH_LONG).show();
    }
}));

So the whole adapter code looks like the following.

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

    public interface OnItemClickListener {
        void onItemClick(ContentItem item);
    }

    private final List<ContentItem> items;
    private final OnItemClickListener listener;

    public ContentAdapter(List<ContentItem> items, OnItemClickListener listener) {
        this.items = items;
        this.listener = listener;
    }

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

    @Override public void onBindViewHolder(ViewHolder holder, int position) {
        holder.bind(items.get(position), listener);
    }

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

    static class ViewHolder extends RecyclerView.ViewHolder {

        private TextView name;
        private ImageView image;

        public ViewHolder(View itemView) {
            super(itemView);
            name = (TextView) itemView.findViewById(R.id.name);
            image = (ImageView) itemView.findViewById(R.id.image);
        }

        public void bind(final ContentItem item, final OnItemClickListener listener) {
            name.setText(item.name);
            Picasso.with(itemView.getContext()).load(item.imageUrl).into(image);
            itemView.setOnClickListener(new View.OnClickListener() {
                @Override public void onClick(View v) {
                    listener.onItemClick(item);
                }
            });
        }
    }
}

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