#include <iostream>
#include <functional>
 
class Button
{
public:
	// Typedef of the event function signature
	typedef std::function<void(Button*)> EventCallback;
 
    Button() : onClick(nullptr) {}
 
	// Set the function to call
	void SetOnClick(EventCallback func) { onClick = func; }
	// Call the function if exists
	void OnClick() {
		if (onClick)
			onClick(this);
	}
 
private:
	// This stores the function pointer for the button
	EventCallback onClick;
};
 
// just some example function that has the same signature as Button::EventCallback
void MyEventFunc(Button* button)
{
	std::cout << "Triggered" << std::endl;
}
 
int main() {
	Button button;
	button.SetOnClick(&MyEventFunc);
	button.OnClick();
	return 0;
}

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