How to add Onclick listener to recycler view

Question

I am developing a simple notepad app first i used listView to show all the notes.But now I am using RecyclerView. While i am using listview i used OnItemClickListener to pass the Data to another activity for editing the note now i am confuse what to do in Recylerview

For listView i am using this

 listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            name = filenames.get(position).getName();
            note = filenames.get(position).getShorttext();
            Alert(); // this method is in main activity 

        }
    });*/  


  public void Alert()
   {
    final AlertDialog dialog;
    View mview = getLayoutInflater().inflate(R.layout.dialog_pass,null);
    final EditText mEdittext = (EditText) mview.findViewById(R.id.Epass);
    AlertDialog.Builder mBuilder = new AlertDialog.Builder(MainActivity.this);
    mBuilder.setView(mview);
    mBuilder.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            String col = mEdittext.getText().toString();
            String password = dBhelper.searchpass(col);
            if (col.equals(password)) {
                Intent intent =  new Intent(MainActivity.this,Note2.class);
                intent.putExtra("Name",name);
                intent.putExtra("Note",note);
                startActivity(intent);
            } else {
                Toast temp = Toast.makeText(MainActivity.this, "Password does not match", Toast.LENGTH_SHORT);
                temp.show();
            }

        }
    });
    mBuilder.setNegativeButton("Cancel",null);
    mBuilder.setCancelable(false);
    dialog = mBuilder.create();
    dialog.show();

     }

Now What Should i Do for Recycle View Please Help

  public class RecycleViewAdapter extends 
  RecyclerView.Adapter<RecycleViewHolder> {// Recyclerview will extend to
  private List<FileName> fileNames;
  private Context context;

  public RecycleViewAdapter(Context context,List<FileName> fileNames) {
    this.context = context;
    this.fileNames = fileNames;

}

@Override
public RecycleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    LayoutInflater mInflater = LayoutInflater.from(parent.getContext());

    ViewGroup mainGroup = (ViewGroup) mInflater.inflate(
            R.layout.grid_item, parent, false);
    RecycleViewHolder listHolder = new RecycleViewHolder(mainGroup);
    return listHolder;

}

@Override
public void onBindViewHolder(RecycleViewHolder holder, final int position) {
    final FileName model = fileNames.get(position);
    RecycleViewHolder mainHolder = (RecycleViewHolder) holder;// holder
    mainHolder.title.setText(model.getName());
    mainHolder.note.setText(model.getShorttext());

}

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

Answer 1

You can handle this using two ways

1). Gesture touch https://www.google.co.in/amp/sapandiwakar.in/recycler-view-item-click-handler/amp/

2).Using interface in adapter https://antonioleiva.com/recyclerview-listener/

I suggest second way using interface

How to use interface for recycleritemclick

public class RecycleViewAdapter extends 
  RecyclerView.Adapter<RecycleViewHolder> {// Recyclerview will extend to
  private List<FileName> fileNames;
  private Context context;

//declare interface 
  private OnItemClicked onClick;

//make interface like this
  public interface OnItemClicked {
        void onItemClick(int position);
  }

  public RecycleViewAdapter(Context context,List<FileName> fileNames) {
    this.context = context;
    this.fileNames = fileNames;
  }

Now assign click to interface

@Override
public void onBindViewHolder(RecycleViewHolder holder, final int position) {
  //............//
  holder.title.setOnClickListener(new View.OnClickListener() {
     @Override
     public void onClick(View v) {
        onClick.onItemClick(position);
     }
  });
}

At the end of the adapter class up from finishing bracket make one method to assign itemclick to interface

public void setOnClick(OnItemClicked onClick){
    this.onClick=onClick;
}

In MainActivity.java Bind the item click with adapter

public class MainActivity extends Activity implements OnItemClicked {
 
    private RecyclerView mRecyclerView;
    private CityAdapter mAdapter;
    private List<City> cities;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_city);

        mRecyclerView = (RecyclerView)findViewById(R.id.list);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
        
        mAdapter = new CityAdapter(cities, R.layout.row_city, this);
        mRecyclerView.setAdapter(mAdapter);
 
        mAdapter.setOnClick(MainActivity.this); // Bind the listener
    }
 
    @Override
    public void onItemClick(int position) {
    // The onClick implementation of the RecyclerView item click
    //ur intent code here
    }
}

For Kotlin code please refer How to handle recyclerview item click in kotlin?

More queries? comment.

Answer 2

Simplest solution would be to access the "itemView" public variable of holder class and set onClickListener on this.

@Override
public void onBindViewHolder(ViewHolder holder, final int position) {
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(context, NewActivity.class);
                intent.putExtra("FileName", list.get(position));
                context.startActivity(intent);
            }
        });        
}