Form::add

public function add($field)
{
	if (!($field instanceof Base))
	{
		$field = $this->convertToField($field);
	}

	if ($field->getKey())
	{
		$this->fields[$field->getKey()] = $field;
	}
	else
	{
		$this->fields[] = $field;
	}
	$field->setForm($this);
	return $this;
}