Welcome to the Treehouse Community
Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.
Start your free trialIbrahim Al-Khalidi
414 PointsRepeted array ( same array as not changeble writted in changebles arrays)!?
At time 3:12 the first Array ( changeble ) it is the same array mentioned in the notchangebles arrays ( the last one)?
Could you please clearify that :)
The array I mean is :
NSArray *nameArray [NSArray arrayWithObjects: @"Andrew", @"Kenneth", @"Craig", @"Kenneth", nil];
Thank you
1 Answer
Amit Bijlani
Treehouse Guest TeacherThey are two separate definitions :
-
The first one declaring an
NSArray
which is an unchangeable array.NSArray *nameArray = [NSArray arrayWithObjects: @"Andrew", @"Kenneth", @"Craig", @"Kenneth", nil];
-
The second one has two declarations one using the convenience constructor:
NSMutableArray *nameArray2 = [NSMutableArray arrayWithObjects: @"Andrew", @"Kenneth", @"Craig", @"Kenneth", nil];
Notice that the classname is
NSMutableArray
, mutable means that the array can be modified after declaration. -
You can also declare it using the designated initializer:
NSMutableArray *nameArray3 = [[NSMutableArray alloc] initWithObjects: @"Andrew", @"Kenneth", @"Craig", @"Kenneth", nil];
Here we are using the
alloc
andinit
approach. Bot the declarations above has the same desired effect.