function __construct()
{
parent::__construct();
$this->fields = NULL;
$this->attributes = array('class' => 'contentTable', 'cellspacing' => 0, 'cellspadding' => 0);
$this->template = NULL;
$this->row_attr = array();
$this->show_line_id = false;
$this->trim_columns = false;
}