How to change position of UIPageControl in iOS >=8.0?

Question

I have a simple UIPageViewController which displays the default UIPageControl at the bottom of the pages. I wonder if it's possible to modify the position of the UIPageControl, e.g. to be on top of the screen instead of the bottom. I've been looking around and only found old discussions that say I need to create my own UIPageControl. Is this thing simpler with iOS8 and 9? Thanks.

Answer 1

Yes, you can add custom page controller for that.

self.pageControl = [[UIPageControl alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height - 50, self.view.frame.size.width, 50)]; // your position

[self.view addSubview: self.pageControl];

then remove

- (NSInteger)presentationCountForPageViewController:(UIPageViewController *)pageViewController

and

- (NSInteger)presentationIndexForPageViewController:(UIPageViewController *)pageViewController

Then add another delegate method:

- (void)pageViewController:(UIPageViewController *)pageViewController willTransitionToViewControllers:(NSArray<UIViewController *> *)pendingViewControllers
 {
     PageContentViewController *pageContentView = (PageContentViewController*) pendingViewControllers[0];
     self.pageControl.currentPage = pageContentView.pageIndex;
 }

Answer 2

Just lookup PageControl in PageViewController subclass and set frame, location or whatever you want

override func viewDidLayoutSubviews() {
        super.viewDidLayoutSubviews()
        for subView in view.subviews {
            if  subView is  UIPageControl {
                subView.frame.origin.y = self.view.frame.size.height - 164
            }
        }
    }

Answer 3

Override the viewDidLayoutSubviews() of the pageviewcontroller and use this

override func viewDidLayoutSubviews() {
    super.viewDidLayoutSubviews()

    // get pageControl and scroll view from view's subviews
    let pageControl = view.subviews.filter{ $0 is UIPageControl }.first! as! UIPageControl
    let scrollView = view.subviews.filter{ $0 is UIScrollView }.first! as! UIScrollView
    // remove all constraint from view that are tied to pagecontrol
    let const = view.constraints.filter { $0.firstItem as? NSObject == pageControl || $0.secondItem as? NSObject == pageControl }
    view.removeConstraints(const)

    // customize pagecontroll
    pageControl.translatesAutoresizingMaskIntoConstraints = false
    pageControl.addConstraint(pageControl.heightAnchor.constraintEqualToConstant(35))
    pageControl.backgroundColor = view.backgroundColor

    // create constraints for pagecontrol
    let leading = pageControl.leadingAnchor.constraintEqualToAnchor(view.leadingAnchor)
    let trailing = pageControl.trailingAnchor.constraintEqualToAnchor(view.trailingAnchor)
    let bottom = pageControl.bottomAnchor.constraintEqualToAnchor(scrollView.topAnchor, constant:8) // add to scrollview not view

    // pagecontrol constraint to view
    view.addConstraints([leading, trailing, bottom])
    view.bounds.origin.y -= pageControl.bounds.maxY
}