UITableView reload section

Question

I want to reload only one section not the full table. Is there any method in UITableView.

[tableView reloadData] is used to load full table

Answer 1

Based on the accepted answer here, I made a function that will reload all sections in the table using an animation. This could probably be optimized by reloading only visible sections.

[self.tableView reloadData];
NSRange range = NSMakeRange(0, [self numberOfSectionsInTableView:self.tableView]);
NSIndexSet *sections = [NSIndexSet indexSetWithIndexesInRange:range];
[self.tableView reloadSections:sections withRowAnimation:UITableViewRowAnimationFade];

In my case, I had to force a reloadData before the section animation, because the underlying data for the table had changed. It animates properly however.

Answer 2

You need this... For Reload Row

- (void)reloadRowsAtIndexPaths:(NSArray *)indexPaths withRowAnimation:(UITableViewRowAnimation)animation

or For Reload section

- (void)reloadSections:(NSIndexSet *)sections withRowAnimation:(UITableViewRowAnimation)animation

Answer 3

Try to use

[self.tableView beginUpdates]; 
[self.tableView endUpdates];

Hope this will solve your issue.

Answer 4

Yes, there is:

- (void)reloadSections:(NSIndexSet *)sections withRowAnimation:(UITableViewRowAnimation)animation

Answer 5

If you have custom section view you can add a weak reference to it in your view controller and update it whenever you want. Here is my code for reference:

@property (weak, nonatomic) UILabel *tableHeaderLabel;

....

-(UIView *) tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
    UITableViewHeaderFooterView *myHeader = [[UITableViewHeaderFooterView alloc] init];

    UILabel *titleLabel = [[UILabel alloc] init];
    [titleLabel setFrame:CGRectMake(20, 0, 280, 20)];
    [titleLabel setTextAlignment:NSTextAlignmentRight];
    [titleLabel setBackgroundColor:[UIColor clearColor]];
    [titleLabel setFont:[UIFont systemFontOfSize:12]];

    [myHeader addSubview:titleLabel];

    self.tableHeaderLabel = titleLabel; //save reference so we can update the header later

    return myHeader;
}

Then later on you can update your section like this:

- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
    self.tableHeaderLabel.text = [NSString stringWithFormat:@"Showing row: %ld", indexPath.row];
}

Answer 6

But you can reload only sections which contain same number of rows (or you have to manually add or remove them). Otherwise you will get an NSInternalInconsistencyException.

Steps:

1. calculate which rows to remove and/or insert
2. generate an IndexPath array from these
3. call related tableView methods

now you can safely call reloadSections :) Reload section will call update for the rest of the indexes.

Or you can use a library like : https://github.com/onmyway133/DeepDiff

Swift pseodo code:

        tableView.deleteRows(at: valueIndexesToRemove, with: .automatic)
        tableView.insertRows(at: valueIndexesToInsert, with: .automatic)
        tableView.reloadSections(IndexSet([section]), with: .automatic)