I am wanting to learn the singleton method, and I am having an issue with my code. I've been manipulating my own code for a few days now, but decided to use someone else's class to give it a try, and I am still coming up with nothing. Any help would be greatly appreciated. The first class below is the database class and the second class is a user class. Basically, I am trying to figure out what I am doing wrong. I am not getting any database errors, so when I try to echo $user->get_my_avatar(); I get nothing.

class chmdb {
    /**
     * The chmdb database object
     *
     * @access private
     * @var object
     */
    private $chmdb;
 
    /**
     * MySQLi database object
     *
     * @access private
     * @var object
     */
    private static $instance;
 
    /**
     * Current result set
     *
     * @access private
     * @var object
     */
    private $result;
 
    /**
     * The last result (processed)
     *
     * @access private
     * @var array
     */
    private $last_result;
 
    /**
     * The number of rows from last result
     *
     * @access private
     * @var int
     */
    private $row_count;
 
    /**
     * Last error
     *
     * @access private
     * @var string
     */
    private $last_error;
 
    /**
     * PHP5 Constructor
     *
     * Making this function 'private' blocks this class from being directly created.
     *
     * @access private
 
     */
    private function __construct() { }
 
    /**
     * Creates and references the chmdb object.
     *
     * @access public
     * @return object MySQLi database object
     */
    public static function instance() {
        if ( !self::$instance )
            self::$instance = new chmdb();
        return self::$instance;
    }
 
    /**
     * Connect to the MySQL database.
     *
     * @param string $dbHost MySQL hostname
     * @param string $dbUser MySQL username
     * @param string $dbPass MySQL password
     * @param string $dbName MySQL database name
     * @return bool True if successful, false on error.
     */
    public function connect($dbHost, $dbUser, $dbPass, $dbName) {
        // Connect to the database
        $this->chmdb = new mysqli($dbHost, $dbUser, $dbPass, $dbName);
        // Check connection
        if ( mysqli_connect_errno() ) {
            $this->last_error = mysqli_connect_error();
            return false;
        }
        return true;
    }
 
    /**
     * Checks for errors.
     *
     * @return string|false $last_error if it exists or false if no errors.
     */
    public function is_error() {
        if ( isset($this->last_error) && !empty($this->last_error) )
            return $this->last_error;
        return false;
    }
 
    /**
     * Close active connection to MySQL database.
     *
     * @access public
     * @return bool Always returns true.
     */
    public function close() {
        if ( $this->chmdb )
            $this->chmdb->close();
        return true;
    }
 
    /**
     * Executes query and returns results.
     *
     * @access public
     * @param string $sql The SQL statement to execute.
     * @return mixed
     */
    public function query($sql) {
        $this->result = $this->chmdb->query($sql);
        return $this->result;
    }
 
    public function get_results($sql) {
        if ( !$this->query($sql) )
            return false;
 
        $num_rows = 0;
        while ( $row = $this->result->fetch_object() ) {
            $this->last_result[$num_rows] = $row;
            $num_rows++;
        }
 
        $this->result->close();
 
        return $this->last_result;
    }
 
    public function num_rows() {
        return (int) $this->row_count;
    }
 
    /**
     * Retrieve a single row from the database.
     *
     * Do not include LIMIT 1 on the end, as this will be taken care
     * of automatically.
     *
     * @param string $sql The SQL statement to execute.
     * @return object The MySQL row object
     */
    public function get_row($sql) {
        if ( !$results = $this->query($sql . " LIMIT 1") )
            return false;
 
        return $results->fetch_object();
    }
 
    /**
     * Sanitizes data for safe execution in SQL query.
     *
     * @access public
     * @param mixed $data The data to be escaped.
     * @return mixed
     */
    public function escape($data) {
        return $this->chmdb->real_escape_string($data);
    }
 
    /**
     * Prevent cloning of chmdb.
     *
     * @access public
     * @return void
     */
    public function __clone() {
        // Issue E_USER_ERROR if clone is attempted
        trigger_error('Cloning <em>chmdb</em> is prohibited.', E_USER_ERROR);
    }
 
    /**
     * Destructor
     *
     * @access public
     */
    public function __destruct() {}
}
class Users {
 
  public function get_my_avatar() {
  	
  	$chmdb = chmdb::instance();
 	$chmdb->connect($dbHost, $dbUser, $dbPass, $dbName);
 	$result = $chmdb->query("SELECT email, username FROM chm_members WHERE username = 'administrator'");


		while($r = $result->fetch_array) {
		if (defined('UPLOAD_AVATAR')) {
		$filename = CHMEMBER_DIR . 'profile/avatars/'.$r->username.'.gif';
		if(file_exists($filename)) {
		$mypicture = getimagesize(CHMEMBER_URI . '/profile/avatars/' . $r->username . '.gif');
		return '<img src="'.CHMEMBER_URI.'/profile/avatars/'.$r->username.'.gif" '.imgResize($mypicture[1],  $mypicture[1], 55). ' alt="'.$r->username.'"/>';
		} else {
		$mypicture = getimagesize("http://www.gravatar.com/avatar.php?gravatar_id=".md5($r->email));
		return '<img src="http://www.gravatar.com/avatar.php?gravatar_id='.md5($r->email).'" '.imgResize($mypicture[1],  $mypicture[1], 55). ' alt="'.$r->username.'"/>';
		}
		} else {
		$mypicture = getimagesize("http://www.gravatar.com/avatar.php?gravatar_id=".md5($r->email));
		return '<img src="http://www.gravatar.com/avatar.php?gravatar_id='.md5($r->email).'" '.imgResize($mypicture[1],  $mypicture[1], 55). ' alt="'.$r->username.'"/>';
		}
	}


}
		

}

$user = new Users();

In the beginning of your code write following two lines, it will show ur exact error.

error_reporting(E_ALL); 
	ini_set("display_errors", 1);

Thanks, but I already have that in my code, and it doesn't give me any error.

Please disregard this post. I am stupid. I updated some mistakes and it now works.

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