MainActivity.java

import android.content.Context;
import android.database.Cursor;
import android.database.DataSetObserver;
import android.graphics.Color;
import android.net.Uri;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.CursorLoader;
import android.support.v4.content.Loader;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction().replace(android.R.id.content, new SimpleListFragment()).commit();
        }
    }

    public static class SimpleListFragment extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> {


        final static String SELECTED_ITEM = "SELECTED_ITEM";
        private final static String[] projection = new String[]{ContactsContract.CommonDataKinds.Phone._ID, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME, ContactsContract.CommonDataKinds.Phone.NUMBER};
        private final static String orderBy = ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME;
        private final static Uri uri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
        private final static String[] whereArgs = null;


        //private final static String[] projection = new String[]{"_id", "address", "body"};
        //private final static String orderBy = "address";
        //private final static Uri uri = Uri.parse("content://sms/inbox");
        //private final static String[] whereArgs = null;
        //private final static String where = null;

        //        private final static String[] projection = new String[]{MediaStore.Audio.Media._ID, MediaStore.Audio.Media.ARTIST, MediaStore.Audio.Media.ALBUM, MediaStore.Audio.Media.TITLE, MediaStore.Audio.Media.DURATION};
//        private final static String orderBy = MediaStore.Audio.AudioColumns.ARTIST;
//        private final static Uri uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
//        private final static String[] whereArgs = null;
//        private final static String where = null;
        private final static String where = null;
        MyListCursorAdapter adapter;
        RecyclerView recyclerView;

        @Override
        public void onSaveInstanceState(Bundle outState) {
            super.onSaveInstanceState(outState);
            outState.putInt(SELECTED_ITEM, adapter.mSelectedItem);
        }

        @Override
        public void onActivityCreated(@Nullable Bundle savedInstanceState) {
            super.onActivityCreated(savedInstanceState);
            if (savedInstanceState != null) {
                adapter.mSelectedItem = savedInstanceState.getInt(SELECTED_ITEM, -1);
                recyclerView.getLayoutManager().scrollToPosition(adapter.mSelectedItem);
            }
        }


        @Override
        public void onCreate(@Nullable Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            adapter = new MyListCursorAdapter(getActivity(), null);
        }

        @Nullable
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            recyclerView = new RecyclerView(getActivity());
            recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
            recyclerView.setAdapter(adapter);
            return recyclerView;
        }

        @Override
        public void onViewCreated(View view, Bundle savedInstanceState) {
            super.onViewCreated(view, savedInstanceState);
            getActivity().getSupportLoaderManager().initLoader(0, null, this);
        }

        @Override
        public Loader<Cursor> onCreateLoader(int i, Bundle bundle) {
            return new CursorLoader(getActivity(), uri, projection, where, whereArgs, orderBy);
        }

        @Override
        public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
            adapter.swapCursor(cursor);
        }

        @Override
        public void onLoaderReset(Loader<Cursor> loader) {
            adapter.swapCursor(null);
        }
    }

    //from https://gist.github.com/skyfishjy/443b7448f59be978bc59
    public static abstract class CursorRecyclerViewAdapter<VH extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<VH> {

        private Context mContext;

        private Cursor mCursor;

        private boolean mDataValid;

        private int mRowIdColumn;

        private DataSetObserver mDataSetObserver;

        public CursorRecyclerViewAdapter(Context context, Cursor cursor) {
            mContext = context;
            mCursor = cursor;
            mDataValid = cursor != null;
            mRowIdColumn = mDataValid ? mCursor.getColumnIndex("_id") : -1;
            mDataSetObserver = new NotifyingDataSetObserver();
            if (mCursor != null) {
                mCursor.registerDataSetObserver(mDataSetObserver);
            }
        }

        public Cursor getCursor() {
            return mCursor;
        }

        @Override
        public int getItemCount() {
            if (mDataValid && mCursor != null) {
                return mCursor.getCount();
            }
            return 0;
        }

        @Override
        public long getItemId(int position) {
            if (mDataValid && mCursor != null && mCursor.moveToPosition(position)) {
                return mCursor.getLong(mRowIdColumn);
            }
            return 0;
        }

        @Override
        public void setHasStableIds(boolean hasStableIds) {
            super.setHasStableIds(true);
        }

        public abstract void onBindViewHolder(VH viewHolder, Cursor cursor);

        @Override
        public void onBindViewHolder(VH viewHolder, int position) {
            if (!mDataValid) {
                throw new IllegalStateException("this should only be called when the cursor is valid");
            }
            if (!mCursor.moveToPosition(position)) {
                throw new IllegalStateException("couldn't move cursor to position " + position);
            }
            onBindViewHolder(viewHolder, mCursor);
        }

        /**
         * Change the underlying cursor to a new cursor. If there is an existing cursor it will be
         * closed.
         */
        public void changeCursor(Cursor cursor) {
            Cursor old = swapCursor(cursor);
            if (old != null) {
                old.close();
            }
        }

        /**
         * Swap in a new Cursor, returning the old Cursor.  Unlike
         * {@link #changeCursor(Cursor)}, the returned old Cursor is <em>not</em>
         * closed.
         */
        public Cursor swapCursor(Cursor newCursor) {
            if (newCursor == mCursor) {
                return null;
            }
            final Cursor oldCursor = mCursor;
            if (oldCursor != null && mDataSetObserver != null) {
                oldCursor.unregisterDataSetObserver(mDataSetObserver);
            }
            mCursor = newCursor;
            if (mCursor != null) {
                if (mDataSetObserver != null) {
                    mCursor.registerDataSetObserver(mDataSetObserver);
                }
                mRowIdColumn = newCursor.getColumnIndexOrThrow("_id");
                mDataValid = true;
                notifyDataSetChanged();
            } else {
                mRowIdColumn = -1;
                mDataValid = false;
                notifyDataSetChanged();
                //There is no notifyDataSetInvalidated() method in RecyclerView.Adapter
            }
            return oldCursor;
        }

        private class NotifyingDataSetObserver extends DataSetObserver {
            @Override
            public void onChanged() {
                super.onChanged();
                mDataValid = true;
                notifyDataSetChanged();
            }

            @Override
            public void onInvalidated() {
                super.onInvalidated();
                mDataValid = false;
                notifyDataSetChanged();
                //There is no notifyDataSetInvalidated() method in RecyclerView.Adapter
            }
        }
    }


    public static class MyListCursorAdapter extends CursorRecyclerViewAdapter<MyListCursorAdapter.ViewHolder> {

        public int mSelectedItem = -1;

        public MyListCursorAdapter(Context context, Cursor cursor) {
            super(context, cursor);
        }

        @Override
        public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View itemView = LayoutInflater.from(parent.getContext()).inflate(android.R.layout.simple_list_item_2, parent, false);
            final ViewHolder vh = new ViewHolder(itemView);
            vh.mText1.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    final int old = mSelectedItem;
                    mSelectedItem = vh.getAdapterPosition();
                    notifyItemChanged(old);
                    notifyItemChanged(mSelectedItem);
                }
            });
            return vh;
        }

        @Override
        public void onBindViewHolder(ViewHolder viewHolder, Cursor cursor) {
            if (viewHolder.getAdapterPosition() == mSelectedItem)
                viewHolder.mText1.setBackgroundColor(Color.RED);
            else
                viewHolder.mText1.setBackgroundColor(Color.WHITE);
            viewHolder.mText1.setText(cursor.getString(1));
            viewHolder.mText2.setText(cursor.getString(2));
        }

        public static class ViewHolder extends RecyclerView.ViewHolder {
            public final TextView mText1;
            public final TextView mText2;

            public ViewHolder(View view) {
                super(view);
                mText1 = (TextView) view.findViewById(android.R.id.text1);
                mText2 = (TextView) view.findViewById(android.R.id.text2);
            }
        }
    }
}