Adding a search to Ribbit

//search user
protected EditText sUser;
//search button
protected Button sButton;

protected List<ParseObject> sSearchedUser;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_query_friends);

    sUser = (EditText)findViewById(R.id.searchField);
    sButton = (Button)findViewById(R.id.searchButton);
    sButton.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            String searchedUser = sUser.getText().toString();

            searchedUser = searchedUser.trim();

            if (searchedUser.isEmpty()) {
                AlertDialog.Builder builder = new AlertDialog.Builder(QueryFriendsActivity.this);
                builder.setMessage(R.string.search_error_message)
                    .setTitle(R.string.search_error_title)
                    .setPositiveButton(android.R.string.ok, null);
                AlertDialog dialog = builder.create();
                dialog.show();
            }
            else {
                //search for the user!
                setProgressBarIndeterminateVisibility(true);
                //searchedUser.search


                ParseQuery<ParseObject> query = ParseQuery.getQuery(searchedUser);
                query.whereEqualTo("username", searchedUser);
                query.findInBackground(new FindCallback<ParseObject>() {
                    public void done(List<ParseObject> searchList, ParseException e) {
                        if (e == null) {
                            sSearchedUser = searchList;

                            String[] usernames = new String[sSearchedUser.size()];
                            int i = 0;
                            for(ParseObject user : sSearchedUser) {
                                usernames[i] = user.getClassName();
                                i++;
                            }
                            /*ArrayAdapter<String> adapter = new ArrayAdapter<String>(
                                    getListView().getContext(), 
                                    android.R.layout.simple_list_item_checked,
                                    usernames);
                            setListAdapter(adapter);*/
                        } else {
                            Log.d("username", "Error: " + e.getMessage());
                        }
                    }
                });

            }
        }
    });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.query_friends, menu);
    return true;
}