The tableview method viewForHeaderInSection is not called - Swift 5 / iOS14

Question

I read every questions concerning this issue and none of the answers solved my issue.

I'm trying to implement a custom header view to my tableView . However the method viewForHeaderInSection is not called for no reason.

I added the tableView datasource and delegate to the viewController .

I removed the lines of code the add data to my arrays because it would be too long. Consider my arrays are filled. with some My code:

class TransactionsViewController: UIViewController {
        
        lazy var tableView = UITableView()
        var sections = [TransactionsMonthSection]()
        var transactions = [Transaction]()
        
        // ...
        
        override func viewDidLoad() {
                super.viewDidLoad()
                
                // adding some data here ...
        
                commonInit()
                tableView.reloadData()
        }
        
        private func commonInit() {
                
                view.backgroundColor = .clear
                
                tableView.backgroundColor = .systemBackground
                tableView.rowHeight = 74
                tableView.sectionHeaderHeight = 50

                tableView.register(TransactionCell.self, forCellReuseIdentifier: cellId)
                tableView.register(TransactionsHeaderView.self, forHeaderFooterViewReuseIdentifier: TransactionsHeaderView.reuseId)

                tableView.delegate = self
                tableView.dataSource = self

                tableView.contentInsetAdjustmentBehavior = .never
                tableView.separatorInset = UIEdgeInsets(top: 0, left: 32, bottom: 0, right: 16)
                tableView.tableFooterView = UIView()
                
                view.addSubview(tableView)
            }
        
}
        
extension TransactionsViewController: UITableViewDelegate, UITableViewDataSource, UIScrollViewDelegate {
        
          func numberOfSections(in tableView: UITableView) -> Int {
                
                return self.sections.count
          }
            
            
          func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
                
                return sections[section].transactions.count
          }
        
          func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        
                guard let cell = tableView.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as? TransactionCell  else {
                    fatalError("The dequeued cell is not an instance of TransactionCell.")
                }
                return cell
          }
        
          func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
                
                let header = tableView.dequeueReusableHeaderFooterView(withIdentifier: TransactionsHeaderView.reuseId) as! TransactionsHeaderView
                        
                return header
          }
        
          func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
                
                return 50
          }
    }

The method heightForHeaderInSection is called but not viewForHeaderInSection .

Also, if I remove this line: tableView.sectionHeaderHeight = 50 , the method heightForHeaderInSection is not called too.

Is that a bug from Xcode? I never seen that before.

Answer 1

The reason why the tableView 's delegate method viewForHeaderInSection wasn't called is because I was adding the tableView' s delegate in another viewController .

In fact this TransactionsViewController is implemented as a child in another viewController and I need its delegate there. The issue occurred because I was doing this in the parent VC:

transactionsVC.tableView.delegate = self

I'm don't really know why it prevents viewForHeaderInSection to be called though.