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开发者_开发百科. 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?
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];
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)
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?
This is how you do it in Swift 3.0
tableView.beginUpdates()
tableView.headerView(forSection: indexPath.section)?.textLabel?.text = "Some text"
tableView.endUpdates()
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];
Check the documentation for UITableView, or more specifically
-reloadSections:withRowAnimation:
Here's a UITableView extension that's a handy shortcut for refreshing the tableView header/footer titles, based on some of the answers above (note the artificial uppercasing of the header title).
extension UITableView {
func refreshHeaderTitle(inSection section: Int) {
UIView.setAnimationsEnabled(false)
beginUpdates()
let headerView = self.headerView(forSection: section)
headerView?.textLabel?.text = self.dataSource?.tableView?(self, titleForHeaderInSection: section)?.uppercased()
headerView?.sizeToFit()
endUpdates()
UIView.setAnimationsEnabled(true)
}
func refreshFooterTitle(inSection section: Int) {
UIView.setAnimationsEnabled(false)
beginUpdates()
let footerView = self.footerView(forSection: section)
footerView?.textLabel?.text = self.dataSource?.tableView?(self, titleForFooterInSection: section)
footerView?.sizeToFit()
endUpdates()
UIView.setAnimationsEnabled(true)
}
func refreshAllHeaderAndFooterTitles() {
for section in 0..<self.numberOfSections {
refreshHeaderTitle(inSection: section)
refreshFooterTitle(inSection: section)
}
}
}
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)
It worked for me to just reload the section with reloadSections
on my table view
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 ""
}
}
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