Fitting a UIScrollView to a UIView - ios

Question

I am trying to use a UIScrollView to show a series of UIViews. In my storyboard I have a View Controller containing a UIView that is constrained using AutoLayout.
View Controller (UIView in grey)
In order to call the UIScrollView I am using the following method:
func initScrollview() {
self.mainScrollView = UIScrollView(frame: self.mainView.bounds)
self.mainScrollView!.contentSize = CGSizeMake((self.mainView.bounds.width)*CGFloat(3), self.mainView.frame.height)
self.mainScrollView!.backgroundColor = UIColor.greenColor() // For visualization of the UIScrollView
self.mainScrollView!.pagingEnabled = true
self.mainScrollView!.maximumZoomScale = 1.0
self.mainScrollView!.minimumZoomScale = 1.0
self.mainScrollView!.bounces = false
self.mainScrollView!.showsHorizontalScrollIndicator = true;
self.mainScrollView!.showsVerticalScrollIndicator = false;
self.mainScrollView!.delegate = self
for i in 0...3 {
var tempView = SubView(frame: self.mainView.bounds)
pages.insert(tempView, atIndex: i)
self.mainScrollView!.addSubview(pages[i]);
}
self.mainScrollView!.scrollRectToVisible(CGRectMake(mainScrollView!.frame.size.width, 0, mainScrollView!.frame.size.width, mainScrollView!.frame.size.height), animated: false)
}
When I run my code, the UIScrollView does not fit the UIView. Instead it is too short and too wide. The result looks like this:
UIView in grey, UIScrollView in green
What am I doing wrong that is causing the UIScrollView to be incorrectly sized?

Answer 1

You should put the codes that you init the UI element sizes base on the screen size(UIView of UIViewController) in viewDidLayoutSubviews. Because in viewDidLoad, the screen didn't adjust its size yet,

Answer 2

In the above code, there no mention of adding the mainScrollView to the mainVew.
To whose view are you adding the mainScrollView? My opinion would be you are trying to add it to self.view whereas it should be to self.mainView
After the initScrollView() function is called try adding it the below code
self.mainView.addSubview(mainScrollView!)

Answer 3

This would probably be easier if you had placed all these views directly in your storyboard instead of programatically. I don't see anything in your code that can't be done visually in IB. Also, if you have autoLayout active in your storyboard, setting frames and sizes in code won't work. (auto-layout will change your values on the next pass)