private function getButtonLabel($value)
    {
        return $value === null ? $this->emptyButtonLabel : ($value ? $this->checkedButtonLabel : $this->uncheckedButtonLabel);
    }
private function getButtonLabel($value)
    {
        return $value === null ? $this->emptyButtonLabel : ($value ? $this->checkedButtonLabel : $this->uncheckedButtonLabel);
    }
private function getButtonLabel ( $ value ) { return $ value === null ? $ this -> emptyButtonLabel : ( $ value ? $ this -> checkedButtonLabel : $ this -> uncheckedButtonLabel ) ; }
Returns the button label

@param $value

@return string
Returns the button label