Use of UIPageControl with UIScrollView

	UIPageControl in IOS is a control that is used mostly in help screens or info screens for IOS apps. In this we are going to create a small tutorial for custom UIPageControl using UIScrollView and UIPagecontrol in which we will change background color of UIImageView as per page number selected by user on tapping on UIPageControl or swiping UIScrollView. UIScrollView is used with UIPageControl as the page control itself is set of dots and does not has display interface. We are not covering the default UIPageViewController provided by default in xcode. Open ViewController.h and create IBOutlets for UIPageControl and UIScrollView and an IBActionchangePage that we are going to assign to UIPageControl ValueChanged event so that we can detect that user has taped on UIPageControl. @interface ViewController : UIViewController { IBOutlet UIPageControl *pageControl; IBOutlet UIScrollView *scrollView; } -(IBAction)changePage:(id)sender; @end We add three UIImageView to our scroll and set different background color to it. #define SCROLLWIDTH 279
	- (void)viewDidLoad {
	scrollView.contentSize=CGSizeMake(SCROLLWIDTH*3,
	scrollView.frame.size.height);
	scrollView.delegate = self;
	for (int i =0; i<=3; i++) {
	UIImageView *imageView = [[UIImageView alloc]initWithFrame:
	CGRectMake(SCROLLWIDTH*i, 0, scrollView.frame.size.width,
	scrollView.frame.size.height)];
	if (i==0) {
	imageView.backgroundColor = [UIColor redColor];
	}
	else if (i==1) {
	imageView.backgroundColor = [UIColor greenColor];
	}
	else {
	imageView.backgroundColor = [UIColor yellowColor];
	}
	[scrollView addSubview:imageView];
	}
	[super viewDidLoad];
	// Do any additional setup after loading the view, typically from a nib.
	}

Note: SCROLLWIDTH is width of our UIScrollView.

 In our changePage action, we will use scrollRectToVisible  method of UIScrollView so that we can scroll our UIScrollView as per user tap on UIPageControl.

	#pragma mark changePage
	-(IBAction)changePage:(id)sender
	{
	[scrollView scrollRectToVisible:CGRectMake(SCROLLWIDTH*pageControl.currentPage, scrollView.frame.origin.y, SCROLLWIDTH, scrollView.frame.size.height) animated:YES];
	}

Lastly. we ned to implement scrollViewDidEndDecelerating delegate of UIScrollView so that we can calculate page number if user did not use UIPageControl and simple scroll down UIScrollView.

	- (void)scrollViewDidEndDecelerating:(UIScrollView *)sender {
	[self setIndiactorForCurrentPage];
	}
	-(void)setIndiactorForCurrentPage
	{
	uint page = scrollView.contentOffset.x / SCROLLWIDTH;
	[pageControl setCurrentPage:page];
	}