RecyclerView

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content_main.xml
<?xml version="1.0" encoding="utf-8"?>
.xml Class <RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:showIn="@layout/activity_main"
    tools:context=".MainActivity">
 
    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:scrollbars="vertical" />
 
</RelativeLayout>

 Writing the Adapter Class


public class Movie {
    private String title, genre, year;
 
    public Movie() {
    }
 
    public Movie(String title, String genre, String year) {
        this.title = title;
        this.genre = genre;
        this.year = year;
    }
 
    public String getTitle() {
        return title;
    }
 
    public void setTitle(String name) {
        this.title = name;
    }
 
    public String getYear() {
        return year;
    }
 
    public void setYear(String year) {
        this.year = year;
    }
 
    public String getGenre() {
        return genre;
    }
 
    public void setGenre(String genre) {
        this.genre = genre;
    }
}

Create an layout xml named movie_list_row.xml with the below code. This layout file renders a single row in recycler view by displaying movie name, genre and year of release.
movie_list_row.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="?android:attr/selectableItemBackground"
    android:clickable="true"
    android:focusable="true"
    android:orientation="vertical"
    android:paddingBottom="@dimen/row_padding_vertical"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/row_padding_vertical">
 
    <TextView
        android:id="@+id/title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:textColor="@color/title"
        android:textSize="16dp"
        android:textStyle="bold" />
 
    <TextView
        android:id="@+id/genre"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/title" />
 
    <TextView
        android:id="@+id/year"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:textColor="@color/year" />
 
</RelativeLayout>

Now create a class named MoviesAdapter.java and add the below code. Here onCreateViewHolder() method inflates movie_list_row.xml. In onBindViewHolder() method the appropriate movie data (title, genre and year) set to each row

public class MoviesAdapter extends RecyclerView.Adapter<MoviesAdapter.MyViewHolder> {
 
    private List<Movie> moviesList;
 
    public class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView title, year, genre;
 
        public MyViewHolder(View view) {
            super(view);
            title = (TextView) view.findViewById(R.id.title);
            genre = (TextView) view.findViewById(R.id.genre);
            year = (TextView) view.findViewById(R.id.year);
        }
    }
 
 
    public MoviesAdapter(List<Movie> moviesList) {
        this.moviesList = moviesList;
    }
 
    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.movie_list_row, parent, false);
 
        return new MyViewHolder(itemView);
    }
 
    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {
        Movie movie = moviesList.get(position);
        holder.title.setText(movie.getTitle());
        holder.genre.setText(movie.getGenre());
        holder.year.setText(movie.getYear());
    }
 
    @Override
    public int getItemCount() {
        return moviesList.size();
    }
}

Now open MainActivity.java and do the below changes. Here prepareMovieData() method adds sample data to list view.
public class MainActivity extends AppCompatActivity {
    private List<Movie> movieList = new ArrayList<>();
    private RecyclerView recyclerView;
    private MoviesAdapter mAdapter;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
 
        recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
 
        mAdapter = new MoviesAdapter(movieList);
        RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
        recyclerView.setLayoutManager(mLayoutManager);
        recyclerView.setItemAnimator(new DefaultItemAnimator());
        recyclerView.setAdapter(mAdapter);

// row click listener
        recyclerView.addOnItemTouchListener(new RecyclerTouchListener(getApplicationContext(), recyclerView, new RecyclerTouchListener.ClickListener() {
            @Override
            public void onClick(View view, int position) {
                Movie movie = movieList.get(position);
                Toast.makeText(getApplicationContext(), movie.getTitle() + " is selected!", Toast.LENGTH_SHORT).show();
            }
 
            @Override
            public void onLongClick(View view, int position) {
 
            }
        }));
 
        prepareMovieData();
    }
 
    private void prepareMovieData() {
        Movie movie = new Movie("Mad Max: Fury Road", "Action & Adventure", "2015");
        movieList.add(movie);
 
        movie = new Movie("Inside Out", "Animation, Kids & Family", "2015");
        movieList.add(movie);
 
        movie = new Movie("Star Wars: Episode VII - The Force Awakens", "Action", "2015");
        movieList.add(movie);
 
        movie = new Movie("Shaun the Sheep", "Animation", "2015");
        movieList.add(movie);
 
        movie = new Movie("The Martian", "Science Fiction & Fantasy", "2015");
        movieList.add(movie);
 
        movie = new Movie("Mission: Impossible Rogue Nation", "Action", "2015");
        movieList.add(movie);
 
        movie = new Movie("Up", "Animation", "2009");
        movieList.add(movie);
 
        movie = new Movie("Star Trek", "Science Fiction", "2009");
        movieList.add(movie);
 
        movie = new Movie("The LEGO Movie", "Animation", "2014");
        movieList.add(movie);
 
        movie = new Movie("Iron Man", "Action & Adventure", "2008");
        movieList.add(movie);
 
        movie = new Movie("Aliens", "Science Fiction", "1986");
        movieList.add(movie);
 
        movie = new Movie("Chicken Run", "Animation", "2000");
        movieList.add(movie);
 
        movie = new Movie("Back to the Future", "Science Fiction", "1985");
        movieList.add(movie);
 
        movie = new Movie("Raiders of the Lost Ark", "Action & Adventure", "1981");
        movieList.add(movie);
 
        movie = new Movie("Goldfinger", "Action & Adventure", "1965");
        movieList.add(movie);
 
        movie = new Movie("Guardians of the Galaxy", "Science Fiction & Fantasy", "2014");
        movieList.add(movie);
 
        mAdapter.notifyDataSetChanged();
    }
}

Adding RecyclerView Item Click Listener


RecyclerView doesn’t have OnItemClickListener method too to identify item click. You need to write your own class extending RecyclerView.OnItemTouchListener.

Create a class named RecyclerTouchListener.java and extend it from RecyclerView.OnItemTouchListener. You can notice that ClickListener interface also added here.


public class RecyclerTouchListener implements RecyclerView.OnItemTouchListener {
 
    private GestureDetector gestureDetector;
    private ClickListener clickListener;
 
    public RecyclerTouchListener(Context context, final RecyclerView recyclerView, final ClickListener clickListener) {
        this.clickListener = clickListener;
        gestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                return true;
            }
 
            @Override
            public void onLongPress(MotionEvent e) {
                View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
                if (child != null && clickListener != null) {
                    clickListener.onLongClick(child, recyclerView.getChildPosition(child));
                }
            }
        });
    }
 
    @Override
    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
 
        View child = rv.findChildViewUnder(e.getX(), e.getY());
        if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
            clickListener.onClick(child, rv.getChildPosition(child));
        }
        return false;
    }
 
    @Override
    public void onTouchEvent(RecyclerView rv, MotionEvent e) {
    }
 
    @Override
    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
 
    }
 
    public interface ClickListener {
        void onClick(View view, int position);
 
        void onLongClick(View view, int position);
    }
}

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