How to make paging in iPhone?

Hi,
Here is the example of horizontal paging using UIScrollView and its property pagingEnabled.

Look at the below code :

- (void)viewDidLoad
{
    [super viewDidLoad];
    pageCount = 0;
    scrollView.pagingEnabled = YES;
}

#pragma mark ---------------------
#pragma mark User-Defined Methods

-(void)GenerateVideoThumbnail
{
    for (UIView *videoView in self.scrollView.subviews)
    {
        [videoView removeFromSuperview];
        videoView = nil;
    }

    CGFloat X = 12.5,Y = 5.0; // Button X and Y position
    CGFloat Width = 90.0,Height = 90.0;
    CGFloat XDiff = 12.5,YDiff = 5.0;
    NSInteger MaxIconPerRow = 3;  
    NSInteger MaxIconPerPage = 12;

    for (int i=0; i<[arrVideos count]; i++)
    {
        GetVideos *obj_video = [arrVideos objectAtIndex:i];
        UIButton *btnVideo = [UIButton buttonWithType:UIButtonTypeCustom];
        btnVideo.tag = i;
        NSLog(@"frame X: %f, Y: %f",btnVideo.frame.origin.x,btnVideo.frame.origin.y);
        [btnVideo setBackgroundImage:[UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:obj_video.Thumnailpath]]] forState:UIControlStateNormal];

        btnVideo.frame = CGRectMake(X, Y, Width, Height);
        [self.scrollView addSubview:btnVideo];
        [btnVideo startLoading];
        btnVideo = nil;
       
        X = X + Width + XDiff;
        if((i+1)%MaxIconPerRow ==0)
        {
            X = (pageCount*320.0) + XDiff;
            Y = Y + Height + YDiff;
        }
        if((i+1)%MaxIconPerPage ==0)
        {
            ++pageCount;
            X = (pageCount*320.0) + XDiff;
            Y = 5.0;
        }
    }
    self.scrollView.contentSize = CGSizeMake((pageCount*self.scrollView.frame.size.width), self.scrollView.frame.size.height);
}