Question

I just discovered the Build > Analyze feature of XCode today so I am trying to go through and address all the errors it is finding. There are a few lines XCode finds exception with that are confusing me:

    //Test View
    self.imageViewTest = [[UIImageView alloc] init];
    self.imageViewTest.frame = CGRectMake(0, 0, 100, 100); // <=== Leak
    [self.view addSubview:self.imageViewTest];
    //Test View 2
    self.imageViewTestB = [[UIImageView alloc] init];
    self.imageViewTestB.frame = CGRectMake(0, 100, 100, 100); // <=== Leak
    [self.view addSubview:self.imageViewTestB];

and later in my setup of video capture

    self.captureOutput = [[AVCaptureVideoDataOutput alloc] init];
    captureOutput.alwaysDiscardsLateVideoFrames = YES; // <=== Leak

The warning at each of these lines is “Potential leak of an object”. All 3 of these objects are sent the release message in my dealloc method. What could be wrong here?

Thanks!

Answer 1

If you are not using ARC and your properties are setup with the retain attribute, then yes, these are leaks. This line:

self.imageViewTest = [[UIImageView alloc] init];

should be:

UIImageView *iv = [[UIImageView alloc] init];
self.imageViewTest = iv;
[iv release];

or:

self.imageViewTest = [[[UIImageView alloc] init] autorelease];

Or better yet, use ARC. It makes things SO much easier.