void draw(DrawingContext& context, bool selected);
int event(SDL_Event& event, int x_offset = 0, int y_offset = 0);
void draw(DrawingContext& context, bool selected);
int event(SDL_Event& event, int x_offset = 0, int y_offset = 0);
void add_button(Button button, int id, bool select = false);
void add_pair_of_buttons(Button button1, int id1, Button button2, int id2);
void add_button(Button button, int id, bool select = false);
void add_pair_of_buttons(Button button1, int id1, Button button2, int id2);