FLTKCallback++

Programming Guide (ver 0.0.2)

FC++ (FLTKCallback++) only extends current fltk callback system. FC++ adds possibility to use any function or member function as fltk callback. Limitation is that this functions can have maximum 2 arguments.

Default fltk callbacks (back compatibility)

FC++ is backcompatible with default fltk callbacks. So it is still possible to use "normal" callbacks and your current (old) code will compile without problems.

void fltk_cllback(Fl_Widget *w, void *p);
...
some_widget->callback(fltk_callback);

Functions as callbacks

With FC++ you can set any function as callback. This means that following functions can be callbacks:

int func_e1(void);
float func_e2(int e);
string func_e3(vector<int> first, int i);
void func_e4(float sime);

To set this functions as callbacks you must do:

some_widget->callback(&func_e1);
some_widget->callback(&func_e2, 3);
...
vector example_vector;
float float_example = 23.455;
...
some_widget->callback(&func_e3, example_vector, 3); 
some_widget->callback(&func_e4, float_example);

You do not have to assign argument values but then default type values will be used. If that type has no default constructor then compile time error will occur.

some_widget->callback(&func_e1);
some_widget->callback(&func_e2);
some_widget->callback(&func_e3); 
some_widget->callback(&func_e4);

Member functions as callbacks

With FC++ you can set any member function as callback. This means that following member functions can be callbacks:

class func_class{
public:
	int func_e1(void);
	float func_e2(int e);
	string func_e3(vector<int> first, int i);
	void func_e4(float sime);
};

To set this member functions as callbacks you must do:

func_class fc;
...
some_widget->callback(&fc, &fc::func_e1);
some_widget->callback(&fc, &fc::func_e2, 3);
...
vector example_vector;
float float_example = 23.455;
...
some_widget->callback(&fc, &fc::func_e3, example_vector, 3); 
some_widget->callback(&fc, &fc::func_e4, float_example);

You do not have to assign argument values but then default type values will be used. If that type has no default constructor then compile time error will occur.

some_widget->callback(&fc, &fc::func_e1);
some_widget->callback(&fc, &fc::func_e2);
some_widget->callback(&fc, &fc::func_e3); 
some_widget->callback(&fc, &fc::func_e4);