pub unsafe extern "C" fn lv_obj_bind_checked(
obj: *mut lv_obj_t,
subject: *mut lv_subject_t,
) -> *mut lv_observer_tpub unsafe extern "C" fn lv_obj_bind_checked(
obj: *mut lv_obj_t,
subject: *mut lv_subject_t,
) -> *mut lv_observer_t