Add touch event listener from another class?

cocos2d-x C++
#1

Hi,
I have a class called “MessageBoxYesNo”. And this class has two buttons. I want to bind touch event listener functions to these two buttons but the functions should be in another class.

I mean;
The class including my buttons: MessageBoxYesNo
The class including callback functions: HelloWorld

For example in my MessageBoxYesNo class, I have followings:

sprButtonYes = ui::Button::create("btnNormal.png", "btnHover.png");
sprButtonNo = ui::Button::create("btnNormal.png", "btnHover.png");

sprButtonYes->setTouchEnabled(true);
sprButtonNo->setTouchEnabled(true);

sprButtonYes->addTouchEventListener(CC_CALLBACK_2(HelloWorld::buttonYes1Pressed, this));
sprButtonNo->addTouchEventListener(CC_CALLBACK_2(HelloWorld::buttonNo1Pressed, this));

I defined buttonYes1Pressed and buttonNo1Pressed in my “HelloWorldScene.cpp”. But it doesn’t recognize. I also tried including “HelloWorldScene.h” now it gives me error (std::invoke bla bla). I don’t know what to do please help me, thanks.

#2

Please help

#3

Why not just extend TouchEventListener to make your own touch events and then you can add them to as many classes as you want.

#5

How can I do that

#6 
class myTouchEvent : public cocos2d:CCEventTouch
{

}

look at CCEventTouch.h for what needs implementing.

1 Like
#8

Sorry I still don’t understand. What should I change inside my own touch event class? What is the point of extending TouchEventListener. I don’t get it

#9

What you want to do is a callback?
sample:

class MessageBoxYesNo : public cocos2d::Node {
public:
...
    void setClickYesButtonCallback(const std::function<void()>& callback);
    void setClickNoButtonCallback(const std::function<void()>& callback);

private:
...
    std::function<void()> mClickYesCallback;
    std::function<void()> mClickNoCallback;
    bool init() override;
}

MessageBoxYesNo::MessageBoxYesNo() :
    mClickYesCallback(nullptr),
    mClickNoCallback(nullptr)
{
}

MessageBoxYesNo::setClickYesButtonCallback(const std::function<void()>& callback) {
    mClickYesCallback = callback;
}

MessageBoxYesNo::setClickNoButtonCallback(const std::function<void()>& callback) {
    mClickNoCallback = callback;
}

bool MessageBoxYesNo::init() {
    if(!Node::init()) {
        return false;
    }

    ...
    sprButtonYes = ui::Button::create("btnNormal.png", "btnHover.png");
    sprButtonNo = ui::Button::create("btnNormal.png", "btnHover.png");
    ...
    addChild(sprButtonYes);
    addChild(sprButtonNo );

    sprButtonYes->addClickEventListener([this](Ref*) {
        if(mClickYesCallback) {
            mClickYesCallback();
        }
    });

    sprButtonNo->addClickEventListener([this](Ref*) {
        if(mClickNoCallback) {
            mClickNoCallback();
        }
    });

    return true;
}


void HelloWorld::showMessageBox() {
    auto box = MessageBoxYesNo::create();
    box->setClickYesButtonCallback([this] {
        CCLOG("click yes");
    });
    box->setClickNoButtonCallback([this] {
        CCLOG("click no");
    });
    addChild(box);
}
#11

This worked, thanks…

#12

Doesn’t it sort of break encapsulation calling events from some other class inside the class you really want them in?

#14

You are right but I’m unfamiliar with listeners, events and classes so I’m unable to create my own touch class and I’m unable to change it as I want.