isProtected()) {
            $value = $this->protected;
            $disable = ' disabled="disabled"';
        } else {
            $value = is_null($this->local) ? $this->default : $this->local;
        }
        // ensure current value is included
        if(!in_array($value, $this->choices)) {
            $this->choices[] = $value;
        }
        // disable if no other choices
        if(!$this->isProtected() && count($this->choices) <= 1) {
            $disable = ' disabled="disabled"';
            $nochoice = $plugin->getLang('nochoice');
        }
        $key = htmlspecialchars($this->key);
        $label = '';
        $input = "
\n";
        $input .= ' $nochoice \n";
        $input .= "
\n";
        return array($label, $input);
    }
    /** @inheritdoc */
    public function update($input) {
        if(is_null($input)) return false;
        if($this->isProtected()) return false;
        $value = is_null($this->local) ? $this->default : $this->local;
        if($value == $input) return false;
        if(!in_array($input, $this->choices)) return false;
        $this->local = $input;
        return true;
    }
}