靜態類可以擴展非靜態類並訪問其方法嗎？

Question

我有一個充當Smarty包裝器的類，但希望在我的應用程序中靜態使用它。

我的設置看起來像這樣：

class Template extends Smarty {

    public function __constructor() {

         parent::__constructor();
    }

    public function setSettings() {

         $this-> some smarty settings here
    }

    public static function loadTpl($tpl) {

         self::$tplFile = $tpl;

         // other logic

         self::setSettings(); // this won't get executed because it uses non static method calls.
    }
}

我該如何解決？

Answer 1

與其嘗試將其包裝為全部被靜態調用，不如創建一個單例實例並調用Template::getInstance()來檢索它，而不是new Smarty() ：

class Template extends Smarty {
  public static $instance = NULL;

  // Private constructor can't be called
  private function __construct() {
    parent::__construct();
  }

  // Instead instantiate or return the existing instance
  public static function getInstance () {
    return self::$instance ? self::$instance : new self();
  }
}


// Instantiate as:
$smarty = Template::getInstance();