Delegation mechanism in cocos2d-x

I encountered a problem in today's project.

A is a layer with an action in it. Once a is initialized, this action will be executed.

B is a scenario. I added A to B, but after the action in a is executed, B immediately executes another method.

 

The problem arises. How can I know in B that the action execution in a is complete, and with the help of my colleagues, I will soon be OK. The principle is to use the delegation mechanism.

 

Solution:

1. Create a new class C with a virtual function.

class C{public:    virtual void animFinished(){};    };

2. Let B inherit C.

Class B: Public c {public: Virtual void animfinished (); // If action in a is complete, B will execute the following method void mdonext ();};

In implementation

Adding a is a member variable added to B, which has been initialized.

Then pass B to. (A must have a member variable C)

a->delegate_=this;void B::animFinished(){    mDoNext();}

 

3. Implementation of Class

class A:public CCLayer{public:    C* delegate_;};

 

In implementation, after an action in a is executed, we only need to start the method in B in the Action callback function.

void A::mCallBack(){        if (delegate_) {        delegate_->animFinished();    }  }

 

OK, that is, B is delegated to a, let a start the method in B. I figured it out.