Question

I want to sort NSMutableArray which have NSInteger values inside. I tried to use this solution:

 NSArray *sorted = [array sortedArrayUsingSelector:@selector(compare:)];

It almost worked, so i want to ask why not everything alright with it. Here is example of data:

not sorted = (
    30,
    42,
    54,
    6,
    18
)

 sorted = (
    18,
    30,
    42,
    54,
    6
)

We can see that it sorted everything but 6 value which is at the end off array.

Why this could happened ?

Thank you.

Full method:

- (void) initialize{
    NSInteger min = 30;
    NSInteger interval = 12;
    NSInteger count = floor(60/interval);

    for (int i = 0; i < count; i++) {

        [array addObject:[NSString stringWithFormat:@"%i",min]];
        min +=interval;

        if (min > 60)
            min -= 60;
    }

    //DLog(@"not sorted = %@",minutes);
    array = [[array sortedArrayUsingSelector:@selector(compare:)] mutableCopy];
    //DLog(@"sorted = %@",minutes);

}

Answer 1

You are getting problem in above case because you are sorting string values not a NSNUMBER.
You have to use NSNumber to add objects of integer. Then do something like:

      NSMutableArray *array = [[NSMutableArray alloc ] initWithObjects:
                              [NSNumber numberWithInt:10],    
                              [NSNumber numberWithInt:50],
                              [NSNumber numberWithInt:5],
                              [NSNumber numberWithInt:3],
                              nil];

      NSLog(@"SORTED = %@",[array sortedArrayUsingSelector:@selector(compare:
                                                               )]);

This will give you a sorted array.