如何从此 v8 class 正确创建派生 class

Question

所以我有一个 v8 中的 class，我希望我自己的 class 从中派生，然后实例化我自己的 class.

的一个实例

在 v8 中有 class 带有这个签名：

class V8_EXPORT CodeEventHandler {
 public:
  /**
   * Creates a new listener for the |isolate|. The isolate must be initialized.
   * The listener object must be disposed after use by calling |Dispose| method.
   * Multiple listeners can be created for the same isolate.
   */
  explicit CodeEventHandler(Isolate* isolate);
  virtual ~CodeEventHandler();

  /**
   * Handle is called every time a code object is created or moved. Information
   * about each code event will be available through the `code_event`
   * parameter.
   *
   * When the CodeEventType is kRelocationType, the code for this CodeEvent has
   * moved from `GetPreviousCodeStartAddress()` to `GetCodeStartAddress()`.
   */
  virtual void Handle(CodeEvent* code_event) = 0;

  /**
   * Call `Enable()` to starts listening to code creation and code relocation
   * events. These events will be handled by `Handle()`.
   */
  void Enable();

  /**
   * Call `Disable()` to stop listening to code creation and code relocation
   * events.
   */
  void Disable();

 private:
  CodeEventHandler();
  CodeEventHandler(const CodeEventHandler&);
  CodeEventHandler& operator=(const CodeEventHandler&);
  void* internal_listener_;
};

我自己的派生 class 看起来像这样：

class CodeEventHandler : public v8::CodeEventHandler
{
public:
    ~CodeEventHandler()
    {
        listeners.clear();
    }

    void Handle(v8::CodeEvent* event)
    {
        // code omitted for readibility
    }

    v8::Local<v8::Object> SerializeEvent(v8::CodeEvent* event)
    {
        // code omitted for readibility
    }

    void AddListener(v8::Local<v8::Function> listener)
    {
        // code omitted for readibility
    }

    void SetResource(CV8ResourceImpl* _resource)
    {
        resource = _resource;
    }

private:
    CV8ResourceImpl* resource;
    std::vector<v8::UniquePersistent<v8::Function>> listeners;
};

但是当我想像这样实例化我的 class 时：

v8::Isolate* isolate = v8::Isolate::GetCurrent();
auto codeEventHandler = new CodeEventHandler(isolate);

我收到这个错误：

error C2664: 'CodeEventHandler::CodeEventHandler(const CodeEventHandler &)': cannot convert argument 1 from 'v8::Isolate *' to 'const CodeEventHandler &'

我做错了什么？

Answer 1

（这不是特定于 V8 的问题；它是普通的 C++。）

正如@JosephLarson 指出的那样，您需要一个具有正确签名的构造函数。将此添加到您的 class:

explicit CodeEventHandler(Isolate* isolate)
    : v8::CodeEventHandler(isolate) {
  // any code you need to initialize your subclass instances...
}

如何从此 v8 class 正确创建派生 class

How to properly create a derived class from this v8 class

c++

v8