std :: function的初始化不会计算为带有3个参数的函数

Question

GameObject类.h + .cpp：

typedef std::function<void(GameObject* triggerobject, GameObject* otherobject, TriggerAction action)> PhysicsCallback;

    void GameObject::OnTrigger(GameObject* triggerobject, GameObject* otherobject, TriggerAction action)
    {
        if (m_OnTriggerCallback)
            m_OnTriggerCallback(triggerobject, otherobject, action);
    }

    void GameObject::SetOnTriggerCallBack(PhysicsCallback callback)
    {
        m_OnTriggerCallback = callback;
    }

其他课程：

m_pSphere->SetOnTriggerCallBack(*pCbObj);
m_pSphere->OnTrigger(m_pWallLeft, m_pSphere, GameObject::TriggerAction(0));

我想要使用OnTrigger（）函数来设置m_OnTriggerCallback。当我试图传递相应的论点时，我真的陷入困境。在没有编译器错误的情况下，似乎几乎不可能将PhysicsCallback初始化。

我试过了： std::function<void(GameObject* triggerobject, GameObject* otherobject, GameObject::TriggerAction action)> *obj; *obj = (m_pWallRight, m_pSphere, GameObject::TriggerAction(0));

但没有运气。 * obj不接受任何论据。以下这些行给出了相同的错误：

GameObject::PhysicsCallback *pCbObj; = new GameObject::PhysicsCallback(new std::function<void()>()); //term does not evaluate to a function taking 3 arguments
    GameObject::PhysicsCallback *pCbObj = new GameObject::PhysicsCallback((m_pWallRight, m_pSphere, GameObject::TriggerAction(0)));

这一行*pCbObj = GameObject::PhysicsCallback(m_pWallRight, m_pSphere, GameObject::TriggerAction(0));给出了这个智能感知错误： http://puu.sh/gi29n/95f0f7855b.png

我真的很困惑，如何使用SetOnTriggerCallBack函数？

Answer 1

做

m_pSphere->OnTrigger(m_pWallLeft, m_pSphere, GameObject::TriggerAction(0));

实际上，

以GameObject::TriggerAction为参数调用0。然后，它传递结果。

什么是GameObject::TriggerAction？这是静态方法吗？这应该是因为，否则，您要std::bind到object instance或直接应用它。

Answer 2

使用lambda，我能够创建一个编译器可接受的参数：

GameObject::PhysicsCallback trigger = [=](GameObject* triggerobject, GameObject* otherobject, GameObject::TriggerAction action){};