bool (*surface_activate_by_default)(struct ivi_surface *surf, void *user_data);
bool (*surface_advertise_state_change)(struct ivi_surface *surf, void *user_data);
bool (*surface_activate_by_default)(struct ivi_surface *surf, void *user_data);
bool (*surface_advertise_state_change)(struct ivi_surface *surf, void *user_data);