Memory leak issue with UIImagePickerController

Question

I'm getting memory leak with UIImagePickerController class.

Here's how I'm using it:

    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
    [self presentModalViewController:picker animated:YES];
    [picker release];

To remove the picker i call [picker dismissModalViewControllerAnimated:YES]; in didFinishPickingImage and imagePickerControllerDidCancel.

--

Instruments show around 160bytes leaking as a result of this instruction:

+[UIImagePickerController _loadPhotoLibraryIfNecessary]

Apparently this issue has and is disturbing many people, and solution to avoid this problem is to build a singleton class dedicated for picking images from library or capturing using device's build in camera.

Anyone want to add something?

Answer 1

As the author of one of the first articles about the necessity to use a singleton, the motivation was to prevent a crash on the 7/8th image capture, not because of any particular worry about the leak. 160 bytes is annoying, but not a major problem, and therefore not worth worrying about (because it can't be fixed by developers).

Answer 2

Have you tried deleting the delegate line? I’ve had similar problems with AVAudioPlayer when delegating to self. (Even though the accessor says assign in both cases.) If the leak goes away with the delegation, you can delegate to a different object.

Answer 3

I was having a memory alloc leak which I found in Instruments. All I was doing was opening and closing the image picker (open/cancel) and using Apple code, my code and other people's code.

All were showing the allocation going up and up each time, as if the picker was not being released. If you tried to release it, it would crash (over released).

Then I found a really helpful web page which basically stated:

"This doesn't happen when testing on the device"

So I switched from the simulator and ran the tests on the device. Lo & behold there was no allocation increase and it behaved normally.

This however is totally evil and now we can place no trust in the simulator to do a reliable job. Whether this is pertinent to your specific problem or not, I took you up on anything else to add, and my thing to add is don't test memory on the simulator!

Answer 4

The reason maybe that you forget to release image. Because each time you write

UIImageView.image = image_a;

Then , image_a will get retained once.

Until you let UIImageView.image = nil, when image_a can be release finally.

I resolved my problem in this way.

Answer 5

If you see memory leaks several GeneralBlock and SegmentMachO by using UIImagePickerController,

Try by adding CoreLocation framework and MapKit framework to your project. I don't see anymore memory leaks in the instrument tool leak checking. I don't know how UIImagePickerController related to these frameworks. I am not sure it is good solution or not. "adding frameworks without using or necessary".

I have also got the memory leak by using UIImagePickerController. That memory leak happen even in the sample code "PhotoLocation" and "iPhoneCoreDataRecipes" downloaded from developer.apple.com. I also checked by adding these frameworks to those downloaded sample code. There is no memory leaks anymore.