iphone programming + memory leak

I am getting memory leak theFileName = [[responseString lastPathComponent]stringByDeletingPathExtension];

theFileName is a global variable. I have synthesized it and

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]))
 开发者_如何学Go   {
        // Custom initialization
        theFileName = [[NSString alloc] init];
        }
    return self;
}

- (void)requestFinished:(ASIHTTPRequest *)request{

    //internally calls this function
    // Use when fetching text data
    NSString *responseString = [request responseString];
    //NSLog(@"the responsestring for download is:%@",responseString);
    theFileName = [[responseString lastPathComponent]stringByDeletingPathExtension];
    //NSLog(@"the theFileName for download is:%@",theFileName);
    //adds extension  .jpg to file name
    NSString *jpg=@".jpg";
    NSString *addjpg=[theFileName stringByAppendingString:jpg];
    //NSLog(@"append %@",addjpg);
}

Released it in dealloc.

-(void)dealloc
{
[thefileName release];
}
}

theFileName = [[responseString lastPathComponent]stringByDeletingPathExtension];

creates a new object for theFileName, which already holds an NSString object. You need to release that old value before, i.e.

[theFileName release];
theFileName = [[responseString lastPathComponent]stringByDeletingPathExtension];

You might consider using a copy (recommended) or retain property for theFilename, and use the dot-syntax in requestFinished:.

Here are a few things that might help.

1. You're not calling super's dealloc method within self's dealloc. For example,

   - (void) dealloc { [self.theFileName release]; [super dealloc]; }

2. You're not using the getters and setters that come with synthesizing a property, and we don't know what property you've used with theFileName. If you've got a retaining property, i.e. a statement like @property (copy) NSString * theFileName then you should use the setter so that you don't trip up on retain counts. For example,

   • (id) initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) { // Custom initialization NSString * aFileName = [[NSString alloc] init]; [self setTheFileName:aFileName]; [aFileName release]; } return self; }

is better.