ios - Reload section without reloading section header

Question

I have a UITableView, where there is a UISegmentedControl in the header view. It should work exactly like in the App Store app: As the user scrolls, the title in the header scrolls off the screen but the segmentedControl sticks under the navigationBar.

When the user selects a segment, the section below the header should be reloaded with a nice UITableViewRowAnimation. However, as I call tableView:reloadSections:withRowAnimation:, the header view is animated as well, which I want to prevent, because it looks terrible.

Here's my code for this:

- (void)selectedSegmentIndexChanged:(UISegmentedControl *)sender
{
    int index = sender.selectedSegmentIndex;
    if (index < self.oldIndex) {
        [self.tableView reloadSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationLeft];
    } else if (index > self.oldIndex) {
        [self.tableView reloadSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationRight];
    }
    self.oldIndex = index;
}

Anyone has an idea how to reload the section below the header without reloading the header itself?

Answer 1

Maybe you should try with

[self.tableView reloadRowsAtIndexPaths:[self.tableView indexPathsForVisibleRows] withRowAnimation:UITableViewRowAnimationLeft] //or UITableViewRowAnimationRight

However, I'm not sure but I think it can rise some error in the case where you have less rows to reload than previously.

---

Edit

I think you could deal with [tableView beginUpdates] and [tableView endUpdates] to solve your problem.

For example, you have 2 arrays of data to display. Let name them oldArray and newArray. A sample of how what you could do :

- (void)selectedSegmentIndexChanged:(UISegmentedControl *)sender
{
    [self.tableView setDataSource: newArray];
    int nbRowToDelete = [oldArray count];
    int nbRowToInsert = [newArray count];

    NSMutableArray *indexPathsToInsert = [[NSMutableArray alloc] init];
    for (NSInteger i = 0; i < nbRowToInsert; i++) {
        [indexPathsToInsert addObject:[NSIndexPath indexPathForRow:i inSection:section]];
    }

    NSMutableArray *indexPathsToDelete = [[NSMutableArray alloc] init];
    for (NSInteger i = 0; i < nbRowToDelete; i++) {
        [indexPathsToDelete addObject:[NSIndexPath indexPathForRow:i inSection:section]];
    }

    [self.tableView beginUpdates];
    [self.tableView deleteRowsAtIndexPaths:indexPathsToDelete withRowAnimation:UITableViewRowAnimationLeft];
    [self.tableView insertRowsAtIndexPaths:indexPathsToInsert withRowAnimation:UITableViewRowAnimationRight];
    [self.tableView endUpdates];
}