Center UIPageControl after orientation change

Question

I'm trying to centralize a UIPageControl in portrait and landscape modes, but it isn't working, the x changes after device rotation.

@interface DetailViewController : UIViewController<UIScrollViewDelegate>
{
    UIPageControl *pageControl;
}

- (void)viewDidLoad
{
    pageControl = [[UIPageControl alloc] init] ;  
    [self renderMyView];
    [self.view addSubview:pageControl];
}

- (void)renderMyView
{
   if(isPortrait)
   {
        pageControl.frame = CGRectMake(200, 976, 0, 0);
   } else {
        pageControl.frame = CGRectMake(200, 720, 0, 0);
   }
}

The renderMyView is executed on didLoad and didRotate.

At first time viewDidLoad works well in portrait and landscape, but if I rotate the device the pageControl appears in a different x != 200.

I've also tried pageControl.center, but it didn't work.

How can I keep it centralized?

Answer 1

1) In viewDidLoad call renderMyView.

2) After device has rotated don't call method renderMyView

3) Replace your renderMyView with this one:

- (void)renderMyView
{
    if(isPortrait)
    {
         pageControl.frame = CGRectMake(200, 976, 0, 0);
    } else {
         pageControl.frame = CGRectMake(200, 720, 0, 0);
    }
    pageControl.autoresizingMask = UIViewAutoresizingFlexibleBottomMargin;
}

So, don't call my renderMyView more then one time. AutoresizingMask will do all you need.

Tell me, please, if it works for you.

PS: For more information about the autoresizingMask, read the UIView Documentation.

Answer 2

probably a very old question, but I'll share my way to center the UIPageControl. Just set the width of the UIPageControl to be the same width as the view's bounds size width. So, In portrait mode it will be 768 and in the landscape it will be 1024. It works for me.

Answer 3

Set the UIView autoresizingMask in code:

pageControl.autoresizingMask = UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleLeftMargin;

Or you can also do this in interface builder.