iiey · May 28, 2019 09:15
diff --git a/createTrackbar.cpp b/createTrackbar.cpp
 class A
 {
 public:
    void handleTrackbar(int value)
    {
       // real work here, can use 'this'
    }

    //workaround not to declare static var used inside
    static void onTrackbar(int value, void* ptr)
    {
        auto obj = static_cast<A*>(ptr);
        obj->handleTrackbar(value);
    }
 };

 createTrackbar(trck_name,
                wnd_name,
                &setting,
                (int)out_max,
                A::onTrackbar,  //now a static member
                this);          //this one must be given
	class A
	{
	public:
	void handleTrackbar(int value)
	{
	// real work here, can use 'this'
	}

	//workaround not to declare static var used inside
	static void onTrackbar(int value, void* ptr)
	{
	auto obj = static_cast<A*>(ptr);
	obj->handleTrackbar(value);
	}
	};

	createTrackbar(trck_name,
	wnd_name,
	&setting,
	(int)out_max,
	A::onTrackbar, //now a static member
	this); //this one must be given