Method apply

library/include/modules/GuiHooks.h:56–63

                }
                inline T_func *next() { return hook->next(func); }
                void apply (bool enable)
                {
                    if (enable)
                        hook->add(func);
                    else
                        hook->remove(func);
                    enabled = enable;
                }
                inline void enable() { apply(true); }
                inline void disable() { apply(false); }
                inline bool is_enabled() { return enabled; }