iOS Swift viewForHeaderInSection Not being Called

in Swift 3.0

you can also add tableView.estimatedSectionHeaderHeight = 40 into the viewDidLoad to get viewForHeaderInSection called

In swift 3

You should call

func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
        let rect = CGRect(x: 0, y: 0, width: tableView.frame.size.width, height: 44)
        let footerView = UIView(frame:rect)
        footerView.backgroundColor = UIColor.clear
        return footerView
    }
    func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
        return 44
    }

The viewForHeaderInSection method belongs to the UITableViewDelegate Protocol. You therefore must set the delegate of your table view to your view controller in order to get this callback. You probably did just set the tableview's dataSource as your other methods are called.