Is it possible to use AutoLayout with UITableView's tableHeaderView?

Question

Since I discovered AutoLayout I use it everywhere, now I\'m trying to use it with a tableHeaderView.

I made a subclass of

Answer 1

I was able to achieve it by the following approach (this works for footer the same way).

First, you will need small UITableView extension:

Swift 3

extension UITableView {
    fileprivate func adjustHeaderHeight() {
        if let header = self.tableHeaderView {
            adjustFrame(header)
        }
    }

    private func adjustFrame(_ view: UIView) {
        view.frame.size.height = calculatedViewHeight(view)
    }

    fileprivate func calculatedHeightForHeader() -> CGFloat {
        if let header = self.tableHeaderView {
            return calculatedViewHeight(header)
        }
        return 0.0
    }

    private func calculatedViewHeight(_ view: UIView) -> CGFloat {
        view.setNeedsLayout()
        let height = view.systemLayoutSizeFitting(UILayoutFittingCompressedSize).height
        return height
    }
}

In your view controller class implementation:

// this is a UIView subclass with autolayout
private var headerView = MyHeaderView()

override func loadView() {
    super.loadView()
    // ...
    self.tableView.tableHeaderView = headerView
    self.tableView.sectionHeaderHeight = UITableViewAutomaticDimension
    // ...
}

override func viewWillLayoutSubviews() {
    super.viewWillLayoutSubviews()

    // this is to prevent recursive layout calls
    let requiredHeaderHeight = self.tableView.calculatedHeightForHeader()
    if self.headerView.frame.height != requiredHeaderHeight {
        self.tableView.adjustHeaderHeight()
    }
}

Notes about a header UIView's subview implementation:

1. You have to 100% sure that your header view has the correct autolayout setup. I would recommend to start with simple header view with just one heigh constraint and try out the setup above.

2. Override requiresConstraintBasedLayout and return true:

.

class MyHeaderView: UIView {
   // ...
   override static var requiresConstraintBasedLayout : Bool {
       return true
   }
   // ...
}