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Is it possible to obtain a dynamic table view section header height using Auto Layout?

New in iOS 8, you can obtain 100% dynamic table view cells by simply setting the estimated row height, then layout your elements in the cell using Auto Layout. If the content increases in height, the cell will also increase in height. This is extremely useful, and am wondering if the same feat can be accomplished for section headers in a table view?

Can one, for example, create a UIView in tableView:viewForHeaderInSection:, add a UILabel subview, specify auto layout constraints for the label against the view, and have the view increase in height to fit the label's contents, without having to implement tableView:heightForHeaderInSection:?

The documentation for viewForHeaderInSection states: "This method only works correctly when tableView:heightForHeaderInSection: is also implemented." I haven't heard if anything has changed for iOS 8.

If one cannot do that, what is the best way to mimic this behavior?


J
Jordan H

This is possible. It is new right alongside the dynamic cell heights introduced in iOS 8.

To do this, use automatic dimension for the section header height, and if desired you can provide an estimated section header height. This can be done in Interface Builder when the table view is selected or programmatically:

https://i.stack.imgur.com/u3YTv.png

tableView.sectionHeaderHeight = UITableView.automaticDimension
tableView.estimatedSectionHeaderHeight = 38

//You can use tableView(_:heightForHeaderInSection:) and tableView(_:estimatedHeightForHeaderInSection:)
//if you need to support different types of headers per section

Then implement tableView(_:viewForHeaderInSection:) and use Auto Layout to constrain views as desired. Be sure to fully constrain to UITableViewHeaderFooterView's contentView, especially top-to-bottom so the height can be determined by the constraints. That's it!

func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {    
    let headerView = UITableViewHeaderFooterView()
    headerView.translatesAutoresizingMaskIntoConstraints = false
    headerView.backgroundView = {
        let view = UIView()
        view.backgroundColor = myCustomColor
        return view
    }()

    let headerLabel = UILabel()
    headerLabel.translatesAutoresizingMaskIntoConstraints = false
    headerLabel.text = "Hello World"
    headerView.contentView.addSubview(headerLabel)
    
    NSLayoutConstraint.activate([
        headerLabel.leadingAnchor.constraint(equalTo: headerView.contentView.leadingAnchor, constant: 16),
        headerLabel.trailingAnchor.constraint(equalTo: headerView.contentView.trailingAnchor, constant: -16),
        headerLabel.topAnchor.constraint(equalTo: headerView.contentView.topAnchor, constant: 12),
        headerLabel.bottomAnchor.constraint(equalTo: headerView.contentView.bottomAnchor, constant: -12)
    ])
    
    return headerView
}

That's cool if it works, but the docs don't mention it, and neither did the WWDC session if I recall correctly. The docs for UITableViewAutomaticDimension say "if you return this constant in tableView:heightForHeaderInSection: or tableView:heightForFooterInSection:, UITableView uses a height that fits the value returned from tableView:titleForHeaderInSection: or tableView:titleForFooterInSection: (if the title is not nil)."
This didn't work for me. My section header was able to calculate the height automatically, but it overlaps the cells in the section. I'm setting up my header view using a xib file and setting my constraints in interface builder. Is that my problem? Where are you guys creating the constraints? Thanks!
As promised here is the sample code: github.com/ebetabox/DynamicCellSectionHeight
Another key point here, your table cells need to also be configured for auto height (UITableViewAutomaticDimension) calculation for it to work on the sections.
You must have estimatedSectionHeaderHeight or tableView:estimatedHeightForHeaderInSection: AND sectionHeaderHeight or tableView:heightForHeaderInSection:. Additionally, if you're using the delegate methods, you must return a value larger than 1.00 for the estimate (completely undocumented behavior), otherwise the delegate for height will NOT be called and the default table view header height will be used.
C
Clay Ellis

This can be accomplished by setting (or returning) the estimatedSectionHeaderHeight on your table view.

If your section header is overlapping your cells after setting estimatedSectionHeaderHeight, make sure that you're using an estimatedRowHeight as well.

(I'm adding this answer because the second paragraph contains an answer to an issue that can be found after reading through all of the comments which some might miss.)


Thanks, after setting estimatedRowHeight this works like charm :)
This is true even if you are NOT using UITableViewAutomaticDimension for rows. Thanks for saving me an hour.
M
Maulik Pandya

Got stuck in the same issue where header was getting zero height untill and unless I provide a fixed height in the delegate for heighForHeaderInSection.

Tried a lot of solutions which includes

self.tableView.sectionHeaderHeight = UITableView.automaticDimension
self.tableView.estimatedSectionHeaderHeight = 73

But nothing worked. My cell were using proper autolayouts too. Rows were changing their height dynamically by using the following code but section header weren't.

self.tableView.estimatedRowHeight = 135
self.tableView.rowHeight = UITableView.automaticDimension

The fix is extremely simple and weird too but I had to implement the delegate methods instead of 1 line code for the estimatedSectionHeaderHeight and sectionHeaderHeight which goes as follows for my case.

func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
    return UITableView.automaticDimension
}

func tableView(_ tableView: UITableView, estimatedHeightForHeaderInSection section: Int) -> CGFloat {
    return 73
}

M
Mr.Javed Multani

Swift 4+

working(Tested 100%)

If you need both section as well row with dynamic height based on content then you can use below code:

On viewDidLoad() write this lines:

    self.globalTableView.estimatedRowHeight = 20
    self.globalTableView.rowHeight = UITableView.automaticDimension

    self.globalTableView.sectionHeaderHeight =  UITableView.automaticDimension
    self.globalTableView.estimatedSectionHeaderHeight = 25;

Now we have set row height and section height by using UITableView Delegate methods:

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat
   {
       return UITableView.automaticDimension
   }
   func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {

       return UITableView.automaticDimension

   }

NOTE to this great answer. As of 2020 it seems to be ok to ONLY use the four properties in viewDidLoad.
NOTE to this great answer. As of 2020 you DO need the two "useless" lines giving a estimated height (say, 20 or so).
i
iuriimoz

I tried

self.tableView.sectionHeaderHeight = UITableViewAutomaticDimension;
self.tableView.estimatedSectionHeaderHeight = 25;

but it didn't size correctly header with multiline label. Added this to solve my problem:

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    // Recalculates height
    tableView.beginUpdates()
    tableView.endUpdates()
}

do define the data source functions tableView:estimatedHeightForHeaderInSection and tableView:heightForHeaderInSection instead of defining at viewDidLoad.
I found setting estimatedSectionHeaderHeight is only necessary below iOS 11
This is a great solution. If anyone is facing the 'Height is ambiguous' error, using tableView.reloadData() instead of .beginUpdates() and endUpdates() fixes it.
Still not working for me. I've a label & textfield in header view.
C
Codus

In my case:

set programmatically not work.

self.tableView.sectionHeaderHeight = UITableViewAutomaticDimension.

set in storyboard not work. override heightForHeaderInSection worked.

override func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat { return UITableViewAutomaticDimension }

test enviroment:

Mac OS 10.13.4

XCode Version 9.4.1

Simulator iPhone 8 Plus


M
Matheus Lacerda

Yes, it works for me. I have to make more changes as below:

override func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
    let label = UILabel()

    label.numberOfLines = 0
    label.text          = my own text

    return label
}

b
belotserkovtsev

Swift 5, iOS 12+

The only way it worked for me was

tableView.sectionHeaderHeight = UITableView.automaticDimension
tableView.estimatedSectionHeaderHeight = 40
tableView.estimatedRowHeight = 80

Then setting constraints for custom header view elements so that auto layout engine could determine their x,y position and row height. i.e

NSLayoutConstraint.activate([
    titleLabel.leadingAnchor.constraint(equalTo: contentView.layoutMarginsGuide.leadingAnchor),
    titleLabel.topAnchor.constraint(equalTo: contentView.topAnchor),
    titleLabel.bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: -24)
])

I
Irina

I modified iuriimoz answer. Just replaced viewWillAppear method:

tableView.sectionHeaderHeight = UITableViewAutomaticDimension
tableView.estimatedSectionHeaderHeight = 25


override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    // Recalculates height
    tableView.layoutIfNeeded() 
}

Also add the tableView.layoutIfNeeded() to

override func viewDidAppear(_ animated: Bool) {

    super.viewDidAppear(animated)
    tableView.layoutIfNeeded()
}

For iOS 10

tableView.beginUpdates()
tableView.endUpdates()

have "fade" animation effect on viewWillAppear for me