array sorting error unknown cause

Question

hello i have this array that compares two arrays to see if it contains an object however after testing it with nslog

NSLog (@"1");
favoritesArray = [[NSMutableArray alloc] init];
NSLog (@"2");
//Add items
// favoritesArray = [[NSMutableArray alloc]init];

didContain = [[NSMutableArray alloc]init];
NSLog (@"3");

if ([favoritesArray containsObject:@"one"])
{
    [didContain addObject:@"one"];
    NSLog (@"4");
}

the 4th log doesn appear. does this mean my implementation is wrong of the if it contains an object or it means there is no file present like that?

EDIT here is where i add an array

-(IBAction) addToFavorites {

favoritesArray = [[NSMutableArray alloc] init];
[favoritesArray addObject:@"one"];
NSLog (@"hello");

how come this doesnt show up as the object @"one"

Answer 1

The fourth log doesn't appear because the array doesn't contain the object @"one" -- the NSLog is inside the if statement testing for that case.

With the code as shown, that's correct -- the array will be empty and so it's not surprising there's no @"one".

Presumably the real code does something to put stuff in the array, but since we can't see that it's hard to say anything about it.

EDIT: Although the code you've added to the question for addToFavorites seems straightforward enough, it's still not clear how it relates to the original code. Where is it called from? What is the sequence of events?

One issue in particular is that you seem to be allocating a new array in both locations. If this is the case, then the reason you don't see @"one" appearing is that you are adding it in one array and looking for it in a different one. The fact that they both happen to be called favoritesArray is incidental and just muddies the water.

In fact, it is extremely likely that you shouldn't be allocating the array in either location, but should just be referencing an array that gets allocated only once somewhere else (eg, in your class's designated init method) and then kept as an ivar for the lifetime of your application.