UIView frame size not updating in UITableViewCell (using Constraints)

Question

So I am aligning my collectionView inside my UITableViewCell, however once I launch the app it displays the width of my storyboard UITableViewCell instead of the actual iPad app itself (that changes once I start scrolling). Here is my current code

collectionView.frame.origin.x = collectionView.superview!.frame.width;
print(collectionView.superview!.frame.width)

The app prints this, it starts printing 728 once I start scrolling.

335.0
335.0
335.0
335.0
335.0
728.0
728.0
728.0

So my question is, why does this happen, and how can I make sure I always get the 728 width when aligning my collectionView?

Here are some images to help (the blue background is collectionView , the red background is collectionView.superview

Image of my Storyboard

Image of my app after launching it

Image of my app after scrolling down

Answer 1

At first when you run

print(collectionView.superview!.frame.width)

it prints the storyboard encapuslated height = 335 which is the iphone width you developed the layout with to access the right width inisde the vc's

override func viewDidLayoutSubviews()
 super.viewDidLayoutSubviews()
  // print here
}

or inside the cell

override func layoutSubviews()
 super.layoutSubviews()
  // print here
}