addObject replaces previous object in NSMutableArray

Question

I'm trying to add objects to a NSMutableArray through a for loop. But it seems whenever I add an object it replaces the old one so that I only have one object in the array at the time...

Do you have any idea of what might be wrong?

- (void)viewDidLoad
{
[super viewDidLoad];
LoginInfo *info = [[LoginInfo alloc] init];
info.startPost = @"0";
info.numberOfPosts = @"10";
info.postType = @"1";
getResults = [backendService getAllPosts:info];

for (NSInteger i = 0; i < [getResults count]; i++) {

    Post *postInfo = [[Post alloc] init];
    postInfo = [getResults objectAtIndex:i];

    dataArray = [[NSMutableArray alloc] init];
    [dataArray addObject:postInfo.noteText];
    NSLog(@"RESULT TEST %@", dataArray);

}
}

It's the RESULT TEST log that always shows only the last added string in the output.

wattson12 · Accepted Answer · 2012-08-04 12:37:32Z

10

you are initialising the dataArray inside the for loop, so everytime it is created again (which means there are no objects) and a new object is added

move

dataArray = [[NSMutableArray alloc] init];

to before the for loop

also there is no need to alloc/init the postInfo object when you immediately override it with the object from the getResults array

answered Aug 4, 2012 at 12:37

wattson12

11.2k2 gold badges34 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

matsr · Accepted Answer · 2012-08-04 12:43:57Z

4

You keep re-initializing the array for every run of the loop with this line:

dataArray = [[NSMutableArray alloc] init];

So dataArray is set to a new (empty) array for every run of the loop.

Initialize the array before the loop instead. Try something like this:

dataArray = [[NSMutableArray alloc] init];

for (NSInteger i = 0; i < [getResults count]; i++) {

    PostInfo *postInfo = [getResults objectAtIndex:i];

    [dataArray addObject:postInfo.noteText];

    NSLog(@"RESULT TEST %@", dataArray);

}

answered Aug 4, 2012 at 12:43

matsr

4,2673 gold badges24 silver badges36 bronze badges

Collectives™ on Stack Overflow

addObject replaces previous object in NSMutableArray

2 Answers 2

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related