Crazy array sorting in tableView! sortedArrayUsingSelector help?

My tableView app loads the data into the table view. Everything works perfectly, but the array sorting is kind of messed, like you can see in the picture below. I thought about using the sortedArrayUsingSelector, to straighten things up, but I'm not sure which "sorting method" I should use.

How can I sort this s开发者_如何学编程o the cells are sorted according the numbers? Like the order would be 1. 2. 3. 4. 5. etc NOT 1. 10. 11. 12. 13. 14. 2. 3. ?

Thanks a lot in advance!!

And a two-liner:

NSSortDescriptor *descriptor = [NSSortDescriptor sortDescriptorWithKey:nil ascending:YES comparator:^(id obj1, id obj2) { return [obj1 compare:obj2 options:NSNumericSearch]; }];
rowTitleArray = [rowTitleArray sortedArrayUsingDescriptors:[NSArray arrayWithObject:descriptor]];

Sorry for this convoluted approach, but this does work...

NSArray *rowTitleArray = [[NSArray alloc] initWithObjects:
                          @"10. Tenth", 
                          @"15. Fifteenth", 
                          @"13. Thirteenth", 
                          @"1. First", 
                          @"2. Second", 
                          @"22. TwentySecond", nil];

NSMutableArray *dictionaryArray = [NSMutableArray array];
for (NSString *original in rowTitleArray) {
    NSString *numberString = [[original componentsSeparatedByString:@"."] objectAtIndex:0];
    NSNumber *number = [NSNumber numberWithInt:[numberString intValue]];
    NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:
                          number, @"number", original, @"rowTitle", nil];
    [dictionaryArray addObject:dict];
}
NSSortDescriptor *descriptor = [NSSortDescriptor sortDescriptorWithKey:@"number" ascending:YES];
NSArray *sortedDictionaryArray = [dictionaryArray sortedArrayUsingDescriptors:
                                  [NSArray arrayWithObject:descriptor]];
NSMutableArray *sortedRowTitles = [NSMutableArray array];
for (NSDictionary *dict in sortedDictionaryArray) {
    [sortedRowTitles addObject:[dict objectForKey:@"rowTitle"]];
}
rowTitleArray = [NSArray arrayWithArray:sortedRowTitles];

NSLog(@"%@", rowTitleArray);

Output:

    "1. First",
    "2. Second",
    "10. Tenth",
    "13. Thirteenth",
    "15. Fifteenth",
    "22. TwentySecond"

I will try to think of a more elegant solution.

Here is a more elegant solution:

NSInteger intSort(id num1, id num2, void *context) {
    NSString *n1 = (NSString *) num1;
    NSString *n2 = (NSString *) num2;
    n1 = [[n1 componentsSeparatedByString:@"."] objectAtIndex:0];
    n2 = [[n2 componentsSeparatedByString:@"."] objectAtIndex:0];
    if ([n1 intValue] < [n2 intValue]) {
        return NSOrderedAscending;
    }
    else if ([n1 intValue] > [n2 intValue]) {
        return NSOrderedDescending;
    }
    return NSOrderedSame;
}

rowTitleArray = [rowTitleArray sortedArrayUsingFunction:intSort context:NULL];