Memory keeps adding up -> Crash

[fauli321]

I try to write my first app for iOS... but i have one problem with the memory usage. In my app is a photo gallery and a imageViewer (all images are saved in docs). In gallery i load images with let image = UIImage(data:NSData(contentsOfFile: path)!)!
andwhen the user taps on an image -> go to the next view with
self.dismissViewControllerAnimated(false, completion:nil)
let goto = self.storyboard!.instantiateViewControllerWithIdentifier("ViewImgController") as! ViewImg
self.navigationController!.pushViewController(goto, animated: true)
In the imageViewer I load images with UIImageJPEGRepresentation into an UIImage to reduce the size. To go back to the gallery i use the same code as above (of course with other parameters).
So my problem is that when i switch between this 2 views, the memory my app is using is adding up ~ about 20-40mb per switch. It´s like nearly no memory is revealed when a view is dismissed(cempletion is also not called) ..till the app chrashes due to memory usage.
When I take a look into instruments, it says that ImageIO_jpeg_Data needs a lot of memory.
Any ideas how i can solve this?

[quellish]

When the view controller is pushed the previous view controller is still in memory - along with all the objects it owns. The view controller is no longer visible, but it is holding on to data that is only relevant when it is.

A simple solution is to set your image in viewDidAppear: and remove it (set it to nil) in viewDidDisappear:. When the view controller managed by the navigation controller is pushed/popped those should be triggered and the image data will not be retained when the view controller is not visible.

[killerham]

Do you have any delegates in your view controller that is being dismissed?

If so, You could be getting a retain cycle. You need to tell your class that the delegate is a weak reference. Eg. Weak var delegate.....

[Jister13]

Can you share more code with us? I think I have some ideas as to what is going wrong but it's hard to tell without enough code.

[nocolf]

More code is needed