How to display section header\Tile after sorting uitableview

Question

I am sorting my tableview by Distributor using the code below (it was Alphabetical by product)

    NSSortDescriptor *aSort =[[NSSortDescriptor alloc] initWithKey:@"Dis" ascending:YES];
    [distribArray sortUsingDescriptors:[NSMutableArray arrayWithObject:aSort]];

    NSLog( @"data from table %@", distribArray);

    [self.tableView reloadData];


    NSLog(@"ok2222222222");
    [[NSUserDefaults standardUserDefaults] setValue:@"Dis" forKey:@"ListBy"];
    [[NSUserDefaults standardUserDefaults] synchronize];

I would like to know what the easiest way to display the Distributor name as a Title header above all the products for that Distributor. I currently display the Distributor name in the DetailsView of the cell for each product.

I would like to go from.

Product 1
Acme
Product 2
Acme
Product 3
Acme

To this below and keep my UITableView\Cells

Acme
Product 1
Product 2
Product 3

.... Many Thanks for any help.

Please, show you code. No one can help you without your code. Show what models are you using, table view delegates — NeverBe, Oct 12 '12 at 20:56
You would commonly use a section-header for such task. Those section-headers are visible within the contacts app of iOS and they contain single alphabet letters - they may certainly contain whatever you want them though. They do not scroll out of the visible screen until the next header comes into range. — Till, Oct 12 '12 at 21:18

score 0 · Accepted Answer · answered Oct 12 '12 at 21:29

maybe it is not the fastest way, but i think it is simple

first create a small inner class like this:

@interface ProductSection
@property (strong, nonatomic) NSString* sectionName;
@property (strong, nonatomic) NSMutableArray* products;
@end

then use this instead your sort:

NSSortDescriptor *aSort =[[NSSortDescriptor alloc] initWithKey:@"Dis" ascending:YES];
NSArray* products = [distribArray sortUsingDescriptors:[NSMutableArray arrayWithObject:aSort]];

self.sections = [NSMutableArray array];

NSString* currentDistributor = nil;
for (Product* p in products) {
    if (![p.Dis isEqualToString:currentDistributor]) {
        ProductSection* section = [[ProductSection alloc] init];
        section.sectionName = p.Dis;
        section.products = [NSMutableArray array];
        [self.sections addObject:section];

        currentDistributor = p.Dis;
    }
    ProductSection* section = [self.sections lastObject];
    [section.products addObject:p];

}
[self.tableView reloadData];

where self.sections is a mutable array of ProductSection

next use this in your Table View Data Source:

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [[[self.sections objectAtIndex:section] products] count];

}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return [self.sections count];

}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
[[self.sections objectAtIndex:section] sectionName];

}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
Product* p = [[[self.sections objectAtIndex:indexPath.section] products] objectAtIndex:indexPath.row];
...

}

hope that will help

Thanks for the help just not sure how to implement the inner class. I was under the impression that Objective c does not have inner classes. NO ?????? — AhabLives, Oct 15 '12 at 17:54
ah, you are right, i just mean you can create a very small class in .m file of your view controller. — Ezeki, Oct 15 '12 at 22:09

How to display section header\Tile after sorting uitableview

1 Answers1