Retrieving buffering progress

Currently there is a VLCMediaPlayerStateBuffering state in VLCMediaPlayer. In my app which stream media from network, it enter this buffering state for a long time.

In libvlc, there is a event->u.media_player_buffering.new_cache which is the progress of buffering, which would greatly help this case.

I've tried to add my own event:

static void HandleMediaBufferChanged(const libvlc_event_t * event, void * self)
{
    float newBuffer = event->u.media_player_buffering.new_cache;
    
    @autoreleasepool {
        
        [[VLCEventManager sharedManager] callOnMainThreadObject:(__bridge id)(self)
                                                     withMethod:@selector(mediaPlayerBufferChanged:)
                                           withArgumentAsObject:@(newBuffer)];

        [[VLCEventManager sharedManager] callOnMainThreadDelegateOfObject:(__bridge id)(self)
                                                       withDelegateMethod:@selector(mediaPlayerBufferChanged:)
                                                     withNotificationName:VLCMediaPlayerBufferChanged];
        
    }
}

But it seems all events collapsed to one event: the app only get notified when the progress is 0% or 100%, even the buffering take some time. I wonder if there is any mistake on above lines, and can we have this feature in future VLCKit?