Question

Possible Duplicate:
Objective C Memory Management

My code is showing a memory leak here:

NSMutableArray* newImageArray = [[NSMutableArray alloc] init];
NSMutableArray* newMediaArray = [[NSMutableArray alloc] init];

if (self.categoryIndex == 0) {
    for (int i=1; i < [categoryArray count]; i++)
    {
        newImageArray = [NSMutableArray arrayWithArray:[newImageArray arrayByAddingObjectsFromArray:[self getImageArrayByCategoryIndex:i]]];
    }
}
else {
    newImageArray = [self getImageArrayByCategoryIndex:self.categoryIndex];
}

for (int i=0; i < [newImageArray count]; i++)
{
    Media* media = [[Media alloc] init];
    NSString* imageFile = [newImageArray objectAtIndex: i];

    media.imageFile = [UIImage imageNamed:imageFile];
    media.imageLabel = [[imageFile lastPathComponent] stringByDeletingPathExtension];
    media.soundFile = [appFolderPath stringByAppendingString:[[[imageFile stringByDeletingPathExtension] stringByAppendingString: @".wav"] stringByReplacingOccurrencesOfString: IMAGES_FOLDER withString: SOUNDS_FOLDER]];

    [newMediaArray addObject:media];
}

self.mediaArray = newMediaArray;

[self setNextMediaIndex];

I am not releasing media because it is being used by newMediaArray (which is used by mediaArray, which is used my my main object). Shouldn’t everything get released when I release my main object?

Answer 1

It looks like you are leaking all over the place in a variety of ways

newImageArray gets allocated but never released, additionaly you are overwriting the version that you allocated in the first line of you code with another version. So even if you released it at the end of this code segment, the wrong version would get released. It looks like you don’t even need to allocate this one.

newMediaArray gets allocated but never released, you assign it to a property mediaArray if you are using @synthesize to create the code for that property, depending on how you declared that property, the setter will retain the value i.e. newMediaArray creating a leak.

media gets allocated but never released, it get added to a NSMutableArray which means it will get retained by the array. If your app crashes when you release media in the for loop the problem is somewhere else

The Memory Management Programming Guide is pretty much a must read