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iOS Build a Blog Reader iPhone App Getting Data from the Web Mutable vs Immutable

Posted by Faizan Mohammed
Faizan Mohammed
2,036 Points

Not able to get pass the challenge no.4

It says a method must be called on the "elements" array to remove the last object.

mutablearray.mm 
NSMutableArray *elements=[NSMutableArray array];
[elements addObject:@"Helium"];
[elements addObject:@"Neon"];
[elements addObject:@"Argon"];
[elements removeObject:@"Neon"];
[elements removeObjectAtIndex:1];

1 Answer

Sebastien Thomas
Sebastien Thomas
16,502 Points
Sebastien Thomas
Sebastien Thomas
16,502 Points

Hi Faizan,

The problem is in your first line : you cannot declare and initialise a new array like this.

You can use a shorthand method call to setup an empty array :

NSMutableArray *elements = [];