DefaultMovieAdapter.java

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

    // Store a member variable for the movies
    private ArrayList<Movie> mDefaultMovie;
    // Store the context for easy access
    private Context mContext;
    private Movie currentMovie;

    // Pass in the movies array into the constructor
    public DefaultMovieAdapter(Context context, ArrayList<Movie> movies) {
        mDefaultMovie = movies;
        mContext = context;
    }

    // Easy access to the context object in the recyclerview
    private Context getContext() {
        return mContext;
    }
    /*
     Provide a direct reference to each of the views within a data item
     Used to cache the views within the item layout for fast access
     */
    public static class ViewHolder extends RecyclerView.ViewHolder {
        /*
        Your holder should contain a member variable
        for any view that will be set as you render a row
        */
        public final TextView movieTitleTextView;
        public final ImageView movieTitleImageView;
        /*
        We also create a constructor that accepts the entire item row
        and does the view lookups to find each subview
        */
        public ViewHolder(View itemView) {
            /*
            Stores the itemView in a public final member variable that can be used
            to access the context from any ViewHolder instance.
            */
            super(itemView);
            movieTitleTextView = (TextView) itemView.findViewById(R.id.grid_item_movie_title);
            movieTitleImageView = (ImageView) itemView.findViewById(R.id.grid_item_movie_image);
        }
    }

    @Override
    public DefaultMovieAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View v = LayoutInflater.from(parent.getContext()).
                inflate(R.layout.item_movies, parent, false);
        return new ViewHolder(v);
    }

    @Override
    public void onBindViewHolder(DefaultMovieAdapter.ViewHolder viewHolder, int position) {
        Log.v("############", "onBindViewHolder called");
        // Get the data model based on position
        currentMovie = mDefaultMovie.get(position);
        Log.v("############", "currentMovie called is "+currentMovie.toString());
        Log.v("############", "currentMovie's title is "+currentMovie.getMovieTitle().toString());
        /*
        Set item views based on your views and data model
        TextView textView = viewHolder.movieTitleTextView;
        */
        viewHolder.movieTitleTextView.setText(currentMovie.getMovieTitle());
        Log.v("############", "title is :>>>>>>>>>>>>>>>>>>>>>>>>>>>>>"+currentMovie.getMovieTitle());
        //ImageView button = viewHolder.movieTitleImageView;
        //viewHolder.movieTitleImageView.setImageResource(R.mipmap.ic_launcher);
        String url = "https://image.tmdb.org/t/p/w500/"+currentMovie.getMoviePosterPath().toString();
        Log.v("############", "poster path is :>>>>>>>>>>>>>>>>>>>>>>>>>>>>>"+currentMovie.getMoviePosterPath().toString());
        Picasso.with(getContext())
                .load(url)
                .placeholder(R.mipmap.ic_launcher)
                .into(viewHolder.movieTitleImageView);
    }

    @Override
    public int getItemCount() {
        Log.v("############", "getItemCount called with size "+ mDefaultMovie.size());
        return mDefaultMovie.size();
    }
    public void setMovieData(ArrayList<Movie> weatherData) {
        Log.v("############", "setMovieData Called");
        mDefaultMovie = weatherData;
        Log.v("############", "mDefaultMovie is "+mDefaultMovie);
        notifyDataSetChanged();
        Log.v("############", "notifyDataSetChanged Finished");
    }
}

DefaultMovieFragment.java

public class DefaultMovieFragment extends Fragment implements LoaderManager.LoaderCallbacks<ArrayList<Movie>> {

    private static final int DEFAULT_MOVIE_LOADER_ID = 1;
    ArrayList<Movie> movies;
    DefaultMovieAdapter mAdapter;
    RecyclerView mRecyclerView;

    public DefaultMovieFragment() {
        // Required empty public constructor
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        Log.v("############", "onCreateView called");
        // Inflate the layout for this fragment
        View rootView = inflater.inflate(R.layout.fragment_default_movie, container, false);
        Movie movie = new Movie("ram", 2, "path");
        if (savedInstanceState==null){
            movies = new ArrayList<>();
        }

        //First of all check if network is connected or not then only start the loader
        ConnectivityManager connMgr = (ConnectivityManager)
                getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected()) {

          /* fetch data. Get a reference to the LoaderManager, in order to interact with loaders. */
            startLoaderManager();
            Log.v("############", "startLoaderManager called");
        }

        // Lookup the recyclerview in activity layout
        mRecyclerView = (RecyclerView) rootView.findViewById(R.id.recyclerViewMovies);

        // Create mAdapter passing in the sample user data
        mAdapter = new DefaultMovieAdapter(getActivity(), movies);
        // Attach the mAdapter to the recyclerview to populate items
        mRecyclerView.setAdapter(mAdapter);

        // First param is number of columns and second param is orientation i.e Vertical or Horizontal
        final StaggeredGridLayoutManager gridLayoutManager =
                new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);
        // Attach the layout manager to the recycler view
        mRecyclerView.setLayoutManager(gridLayoutManager);
        // That's all!

        return rootView;
    }

    private void startLoaderManager() {
        LoaderManager loaderManager = getLoaderManager();
        loaderManager.initLoader(DEFAULT_MOVIE_LOADER_ID, null, this);
        Log.v("############", "startLoaderManager finished");
    }


    @Override
    public Loader<ArrayList<Movie>> onCreateLoader(int id, Bundle args) {
        Log.v("############", "onCreateLoader called");
        Uri baseUri = Uri.parse(UrlsAndConstants.DefaultQuery.DEFAULT_URL);
        Log.v("############", "baseUri is "+baseUri.toString());
        Uri.Builder uriBuilder = baseUri.buildUpon();
        Log.v("############", "uriBuilder is "+uriBuilder.toString());
        uriBuilder.appendQueryParameter(API_KEY_PARAM, API_KEY_PARAM_VALUE);
        Log.v("############", "uriBuilder.toString() is "+uriBuilder.toString());
        String urls = "https://api.themoviedb.org/3/discover/movie?api_key=4182aa25bab27d06344e404f65c4ae76";
        return new DefaultMovieLoader(getActivity().getApplicationContext(), urls);
    }

    @Override
    public void onLoadFinished(Loader<ArrayList<Movie>> loader, ArrayList<Movie> movie) {
        Log.v("############", "startLoaderManager finished");
        if (movie.isEmpty()) {
            Log.v("******************", "movies isEmpty");
            return;
        } else {
            Log.v("############", "movies are"+movie);
            // Attach the mAdapter to the recyclerview to populate items

            mAdapter.setMovieData(movie);
            mRecyclerView.setAdapter(mAdapter);
        }
    }

    @Override
    public void onLoaderReset(Loader<ArrayList<Movie>> loader) {
        Log.v("############", "onLoaderReset called");
    }
}

DefaultMovieLoader.java

public class DefaultMovieLoader extends AsyncTaskLoader {

    /**
     * Query URL
     */
    private String mUrl;

    /**
     * Constructs a new {@link DefaultMovieLoader}.
     *
     * @param context of the activity
     * @param url     to load data from
     */
    public DefaultMovieLoader(Context context, String url) {
        super(context);
        mUrl = url;
        Log.v("############", "url is "+mUrl);
    }

    @Override
    protected void onStartLoading() {
        forceLoad();
        Log.v("############", "onStartLoading called");
    }

    /**
     * This is on a background thread.
     */
    @Override
    public ArrayList<Movie> loadInBackground() {
        if (mUrl == null) {
            return null;
        }

        // Perform the network request, parse the response, and extract a list of news.
        ArrayList<Movie> movies = QueryUtils.fetchMovieData(mUrl);
        Log.v("############", "loadInBackground called");
        return movies;
    }
}

fragment_default_movie.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="me.abhishekraj.showmyshow.MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recyclerViewMovies"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scrollbars="vertical"/>
</RelativeLayout>

item_movies.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <ImageView
        android:id="@+id/grid_item_movie_image"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#634500"
        android:layout_gravity="center_horizontal|center_vertical"
        android:adjustViewBounds="true"
        android:scaleType="centerCrop"/>

    <TextView
        android:id="@+id/grid_item_movie_title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/colorAccent"
        android:layout_gravity="center_horizontal|center_vertical"
        android:hint="@string/movieTitleHint"/>
</LinearLayout>