Changing UITableView's section header/footer title without reloading the whole table view

Question

Is there any way to reload the section header/footer of a table view without calling [tableView reloadData];?

In fact, I want to show the number of cells in a table view's section in its section footer. The table view is editable and I delete or insert rows using

– insertRowsAtIndexPaths:withRowAnimation:
– deleteRowsAtIndexPaths:withRowAnimation:

It seems that these methods do not update the section footer. Strangely, when I call these methods the table view data-source method

- (NSString *)tableView:(UITableView *)table titleForFooterInSection:(NSInteger)section 

is called (twice!) but it does not update the table view with the new values!!

Anyone has any idea how to fix this problem?

Answer 1

If you just have a basic text header or footer, you can access them directly:

[tableView footerViewForSection:indexPath.section].textLabel.text = [self tableView:tableView titleForFooterInSection:indexPath.section];

similarly for the header:

[tableView headerViewForSection:indexPath.section].textLabel.text = [self tableView:tableView titleForHeaderInSection:indexPath.section];

Answer 2

This should work:

    UIView.setAnimationsEnabled(false)
    tableView.beginUpdates()

    if let containerView = tableView.footerViewForSection(0) {
        containerView.textLabel!.text = "New footer text!"

        containerView.sizeToFit()
    }

    tableView.endUpdates()
    UIView.setAnimationsEnabled(true)

Answer 3

I managed to do it in an indirect way: I created a UILabel and set it as section header/footer.

- (UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section {
    // update sectionFooterView.text    
    return sectionFooterView;
}

- (void)viewDidLoad {
    // create sectionFooterView in Interface Builder, change the frame here
    // use Font-size:15 , BG-Color: clearColor , text-Color: RGB=(97,105,118) 
    // and Text-alignment:Center to look like table view's original footer
    sectionFooterView.frame = CGRectMake(0, 10, 320, 12);
}

Does anyone know a way to do this without setting a custom footer view?

Answer 4

Here's another way to do it:

UITableViewHeaderFooterView *headerView=[self.tableView headerViewForSection:1];
CATransition *animation = [CATransition animation];
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation.type = kCATransitionFade;
animation.duration = 0.35;
[headerView.textLabel.layer addAnimation:animation forKey:@"kCATransitionFade"];
headerView.textLabel.text=[self tableView:self.tableView titleForHeaderInSection:1];
[headerView.textLabel sizeToFit];

Answer 5

This is how you do it in Swift 3.0

tableView.beginUpdates()
tableView.headerView(forSection: indexPath.section)?.textLabel?.text = "Some text"
tableView.endUpdates()

Answer 6

Check the documentation for UITableView, or more specifically -reloadSections:withRowAnimation:

Answer 7

You can also do it this way

override func tableView(_ tableView: UITableView, titleForFooterInSection section: Int) -> String? {
    switch section {
        case 0:
            return "Some string"
        default:
            return ""
    }
}

Answer 8

I have found that the footer text doesn't update correctly if the text changes from filling one line to multiple ones back to one line. Reseting the label width and height would solve this issue.

    UIView.setAnimationsEnabled(false)
    textLabel.frame = CGRect(x: textLabel.frame.minX,
                             y: textLabel.frame.minY,
                             width: 0,
                             height: 0)
    tableView.beginUpdates()
    textLabel.text = "Your text"
    textLabel.sizeToFit()
    tableView.endUpdates()
    UIView.setAnimationsEnabled(true)