#include <iostream>
#include <functional>
 
class ClassXY
{
    std::function<void()> function;
 
public:
    ClassXY(std::function<void()> f)
        : function(f)
    {}
 
    void call()
    {
        function();  // Calls the function
    }
};
 
class Handler
{
public:
    void HandleButtonEvent()
    {
        std::cout << "Handler::HandleButtonEvent\n";
    }
};
 
int main()
{
    Handler* handler = new Handler;
 
    ClassXY xy(std::bind(&Handler::HandleButtonEvent, handler));
 
    xy.call();
}
 

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