UITableView reloadSections does not trigger viewForFooterInSection?

Question

I'm trying to build an app similar to iOS native Reminders app. Where there's a list of items with header and footer. Each cell contains an UITextView that will dynamic change cell height when user typing. Footer view contains the same cell view, except I want it to be a footer so it would stick to the bottom view. I have cell set to dynamic height.

checklistTable.rowHeight = UITableViewAutomaticDimension
checklistTable.estimatedRowHeight = 60

checklistTable.sectionFooterHeight = UITableViewAutomaticDimension
checklistTable.estimatedSectionFooterHeight = 60

here is the logic for update cell height while typing, this works perfectly for regular cells, but does not work for footer view. I set an breakpoint in viewForFooterInSection, it was never called after initial loading.

func textViewDidChange(_ textView: UITextView) {

    let startHeight = textView.frame.size.height
    let calcHeight = textView.sizeThatFits(textView.frame.size).height

    if startHeight != calcHeight {
        UIView.setAnimationsEnabled(false)
        tableView?.beginUpdates()

        if cellType == .footer {
            tableView?.reloadSections(IndexSet(integer: 0), with: .automatic)
        }

        tableView?.endUpdates()
        UIView.setAnimationsEnabled(true)
    }
}

Can anyone point me to the right direction? Thanks

The API docs only say that this method updates the cells, not the header and footers. — picciano, Mar 02 '17 at 22:26
@nirav yes, viewForFooterInSection gets call initialize. and sometime during scrolling — Joe L, Mar 02 '17 at 23:19
Did you implement tableView:heightForFooterInSection method? It's a prerequisite. — Nirav Bhatt, Mar 03 '17 at 08:50
Hi @Nirav, Just add heightForFooterInSection and return UITableViewAutomaticDimension, still no luck :( — Joe L, Mar 03 '17 at 19:15

score 2 · Answer 1 · answered Mar 02 '17 at 22:24

2

Enabling & disabling animations on UIView & invoking tableView?.beginUpdates() simultaneously looks ambiguous.
Simply, invoking reloadSections should work, like:

if startHeight != calcHeight {

        if cellType == .footer {
            tableView?.reloadSections(IndexSet(integer: 0), with: .automatic)
        }
    }

answered Mar 02 '17 at 22:24

ystack

1,785
12
23

Thanks @ystack. I tried that, and it makes no difference :( – Joe L Mar 03 '17 at 03:48
woah! Have you tried performing a simple `table.reloadData()`? – ystack Mar 03 '17 at 21:39
reloadData would probably redraw the footer. But I'm really looking for an elegant way of update the section footer without reload entire table, reload also cause keyboard to dismiss, which I don't want while user is typing. – Joe L Mar 04 '17 at 02:24

UITableView reloadSections does not trigger viewForFooterInSection?

1 Answers1