尝试创建SceneNode时分配抽象类类型的对象

我有一个我无法用C++解决的问题。尝试创建SceneNode时分配抽象类类型的对象

我有一个叫SceneNode的类。在这个类中，没有任何虚函数，并且在私有成员中，我有一个unique_ptr矢量和一个指向SceneNode对象的原始指针。当尝试分配一个新的SceneNode时，出现以下错误：分配抽象类类型“SceneNode”的对象。

下面的代码：

class SceneNode : public sf::Drawable, 
        public sf::Transformable, 
        private sf::NonCopyable 
{ 

    //OVERVIEW: A SceneNode is a node from the scene graph. It represents a graphical element 
    //A typical SceneNode is (PARENT, CHILDREN, TRANSFORM) 
    //With TRANSFORM containing several information: 
    //TRANSFORM.POS = the position of this 
    //TRANSFORM.ROTATION = the rotation of this 

    //The transformation of this is always relative to its parent 
    //Therefore, TRANSFORM.POS is the position of this, relatively to its parent 


    //NB: - a SceneNode is not copyable ! 
    // - It's an abstract class 

public: 

    //-------------------------------------------- 
    //Typedefs 
    //-------------------------------------------- 
    typedef std::unique_ptr<SceneNode> UniquePtr; 
    typedef sf::Vector2f    Position; 

public: 

    //-------------------------------------------- 
    //Constructors 
    //-------------------------------------------- 
    SceneNode(); 
     //REQUIRES:/
     //MODIFIES: this 
     //EFFECTS: initializes this with this_post.PARENT = no parent 
     //   and this.CHILDREN = { ⦰ } 

public: 

    //-------------------------------------------- 
    //Public member functions 
    //-------------------------------------------- 
    void attachChild(UniquePtr child); 
     //REQUIRES: child != nullptr 
     //MODIFIES: this 
     //EFFECTS: if child == nullptr, stops the program; 
     //   else, this_post.CHILDREN = this.CHILDREN U { child } 

    UniquePtr detachChild(const SceneNode& child); 
     //REQUIRES:/
     //MODIFIES: this 
     //EFFECTS: if child in this.CHILDREN, this_post.CHILDREN = this.CHILDREN \ child && returns a unique_ptr to the child, don't catch it to let it being freed 

    sf::Transform getWorldTransform() const; 
     //REQUIRES:/
     //MODIFIES:/
     //EFFECTS: returns the absolute transformation of this 

    Position getWorldPosition() const; 
     //REQUIRES:/
     //MODIFIES:/
     //EFFECTS: returns the absolute position of this 



private: 

    //-------------------------------------------- 
    //Representation 
    //-------------------------------------------- 
    SceneNode*    mParent; 
    std::vector<UniquePtr> mChildren; 



};`

我能做些什么？在此先感谢

来源

2014-09-23 Victor Amaral

做任何'sf :: Drawable'，'sf :: Transformable'或'sf :: NonCopyable'都有纯粹的虚拟函数，你没有重写？ – clcto 2014-09-23 17:49:16

要回答我自己的问题，是的，他们的确如此：http://sfml-dev.org/documentation/2.0/classsf_1_1Drawable.php – clcto 2014-09-23 17:52:38

@clcto是的 - 所有的都是SFML类，Drawable需要一个Draw（） – Conduit 2014-09-23 17:52:55

看起来你是从像抽象接口sf::Drawable继承，但没有实现他们定义的纯虚函数（Drawable函数）。如果你在你的类中实现这些函数，你应该摆脱编译器错误。

来源

2014-09-23 17:52:40 mattnewport

尝试创建SceneNode时分配抽象类类型的对象

回答

相关问题