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iosswiftstoryboarduipageviewcontroller

IOS PageViewController extra white space at bottom

I have a parent view controller with 2 views.On Top, I have View, that contains Page View Controller and on Bottom I have other view that shows different content.

Everything works well, except getting white space below first view ( Page View Controller) and above second view.

I have added following code for constraints,

let views:[String: Any] = ["pageView": pageViewController.view!]
articleContentView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat:     "H:|-0-[pageView]-0-|",
                                                                     options: NSLayoutConstraint.FormatOptions(rawValue: 0),
                                                                     metrics: nil, views: views))

    articleContentView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|-0-[pageView]-0-|",
                                                                     options: NSLayoutConstraint.FormatOptions(rawValue: 0),
                                                                     metrics: nil, views: views))

If I remove this code , My Page View Controller exceeds its view and occupy full screen. Any suggestionsenter image description here much appriaciated.

Solution

  • The "blank space" is almost certainly the Page View Controller's built-in UIPageControl.

    Here's a quick example, with two views... the top view has a UIPageViewController added as a child view controller, and the Top of the bottom view is constrained to the Bottom of the top view:

    enter image description here

    Notice the "empty space" ...

    Using Xcode's Debug View Hierarchy, it's pretty obvious why:

    enter image description here

    So, if I set a background color on the Top view, I see this:

    enter image description here

    It appears to be empty space, because the default Page Control uses tinted white dots - so we don't see anything on a white background.

    Edit

    The PageControl is automatically shown if your controller's DataSource implements both of these optional methods:

    optional func presentationCount(for pageViewController: UIPageViewController) -> Int

optional func presentationIndex(for pageViewController: UIPageViewController) -> Int

    Removing one or both will automatically remove the page control.