無法創建類

Question

我是ActionScript新手，我正在嘗試創建我的第一個應用程序。我有一個主類 - Sprite的子類。和另一個班級，應該管理一些事件，如鍵盤按鍵。下面是它的初始化：

private var controller:GameObjectController; 
... 
controller = new GameObjectController(this); 

下面是controller:GameObjectController本身：

public class GameObjectController extends InteractiveObject 
{ 
    var textField:TextField; 

    public function GameObjectController(mainSprite: Sprite) 
    { 
    addEventListener(KeyboardEvent.KEY_DOWN, onKeyDown); 

    textField = new TextField(); 
    textField.text = "Hello, World"; 
    mainSprite.addChild(textField); 
    } 

    private function onKeyDown(event: KeyboardEvent):void 
    { 
    textField.text = event.keyCode.toString(); 
    } 

} 

，但是當我試圖運行此，我有一個錯誤：

ArgumentError: Error #2012: Class GameObjectController$ can not be created.

我在做什麼錯誤？

Answer 1

從文檔：InteractiveObject

The InteractiveObject class itself does not include any APIs for rendering content onscreen. To create a custom subclass of the InteractiveObject class, extend one of the subclasses that do have APIs for rendering content onscreen, such as the Sprite, SimpleButton, TextField, or MovieClip classes.

所以我建議試圖繼承雪碧代替，看看是否能解決您的問題。

Answer 2

首先，不要擴展InteractiveObject。由於API說：

The InteractiveObject class itself does not include any APIs for rendering content onscreen. To create a custom subclass of the InteractiveObject class, extend one of the subclasses that do have APIs for rendering content onscreen, such as the Sprite, SimpleButton, TextField, or MovieClip classes.

所以轉而使用（例如）：

public class GameObjectController extends Sprite 
{ 
    .... 
} 

其次，構造函數的參數必須是一樣的擴展類 - 顯示類，這意味着零個參數。

Answer 3

flash.display.InteractiveObject是一個抽象類，不能被子類化。相反，從flash.display.Sprite延伸。

不要忘了導入雪碧，並將你的代碼包：

package 
{ 
    import flash.display.Sprite; 

    public class GameObjectController extends Sprite 
    { 
     var textField:TextField; 

     public function GameObjectController(mainSprite: Sprite) 
     { 
      addEventListener(KeyboardEvent.KEY_DOWN, onKeyDown); 

      textField = new TextField(); 
      textField.text = "Hello, World"; 
      mainSprite.addChild(textField); 
     } 

     private function onKeyDown(event: KeyboardEvent):void 
     { 
      textField.text = event.keyCode.toString(); 
     } 
    } 
}