UITableView custom section footer

Question

We do have a TableViewModel which is implementing the UITableViewDelegate and the UITableViewDataSource. It holds the sections and returns the right rows and elements of our UITableViews.

Now we want to have a custom table view section footer. Therefor we implement the optional public func tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView? so that this returns a UIView from a xib file. This is all fine but it ends up in a wrong footer height. If we use func tableView(_ tableView: UITableView, titleForFooterInSection section: Int) -> String? the footer is displayed correct and the height of the footer is set correct.

So we also have to implement the optional public func tableView(_ tableView: UITableView, estimatedHeightForFooterInSection section: Int) -> CGFloat or the optional public func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat

1. Question: How do i get the height of an UIView which this was instantiated? view.frame.bounds or view.frame.height is always 0.
2. Question: What is the default value Apple uses for the footer and how does it calculate that? I recognised that if we return table.sectionFooterHeight for the default (not our custom footer view) the hight is correct.

TableViewModel:

class TableViewModel: NSObject, UITableViewDelegate, UITableViewDataSource {

    var sections: [TableViewSection] = []

    func numberOfSections(in tableView: UITableView) -> Int {
        return sections.count
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return sections[section].numberOfRowsInTableView(tableView)
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        return sections[(indexPath as NSIndexPath).section].tableView(tableView, cellForRowAtIndexPath: indexPath)
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        sections[(indexPath as NSIndexPath).section].tableView(tableView, didSelectRowAtIndexPath: indexPath)
    }

    func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
        return sections[section].headerText
    }

    func tableView(_ tableView: UITableView, willDisplayHeaderView view: UIView, forSection section: Int) {
        sections[section].tableView(tableView, willDisplayHeaderView: view)
    }

    func tableView(_ tableView: UITableView, titleForFooterInSection section: Int) -> String? {
        return sections[section].footerText
    }

    func tableView(_ tableView: UITableView, willDisplayFooterView view: UIView, forSection section: Int) {
        sections[section].tableView(tableView, willDisplayFooterView: view)
    }

    func tableView(_ tableView: UITableView, shouldShowMenuForRowAt indexPath: IndexPath) -> Bool {
        return sections[(indexPath as NSIndexPath).section].tableView(tableView, cellContentsToCopyAtIndexPath: indexPath, withSender: nil) != nil
    }

    func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
        ??
    }

    func tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
        return sections[section].footerView
    }

    func tableView(_ tableView: UITableView, estimatedHeightForFooterInSection section: Int) -> CGFloat {
        ??
    }
}

Answer 1

I solved it by adding the following method:

func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
    return sections[section].footerViewHeight ?? UITableViewAutomaticDimension
}

And returning the calculated height for the footer in section. It does resize properly and we are able to adjust it. As mentioned, returning the UITableViewAutomaticDimension requires:

// Returning this value from tableView:heightForHeaderInSection: or tableView:heightForFooterInSection: results in a height that fits the value returned from // tableView:titleForHeaderInSection: or tableView:titleForFooterInSection: if the title is not nil.

Answer 2

If you are using auto layout you can still return UITableViewAutomaticDimension in heightForFooterInSection and the footer's height will be automatically calculated. As same with heightForRowAt , heightForFooterInSection must be used in combination with estimatedHeightForFooterInSection. A simple example would look like this:

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

func tableView(_ tableView: UITableView, estimatedHeightForFooterInSection section: Int) -> CGFloat {
    return 18 // or whatever value
}