iOS 4 app flickers and crashes when returning from background mode

[matt78705]

I just converted an iPhone OS 3 app to iOS 4, and once in a while, the screen will flicker and then turn black when the app returns from background mode. Has anyone else experienced this?

Others have suggested that the app could be responding in a funky manner to memory warnings, which sounds plausible. However, I put a break point in every single didReceiveMemoryWarning method, and none of these break points are touched while debugging.

Any advice would be great. Thanks.

[SoulRed12]

Originally Posted by matt78705

I just converted an iPhone OS 3 app to iOS 4, and once in a while, the screen will flicker and then turn black when the app returns from background mode. Has anyone else experienced this?

Others have suggested that the app could be responding in a funky manner to memory warnings, which sounds plausible. However, I put a break point in every single didReceiveMemoryWarning method, and none of these break points are touched while debugging.

Any advice would be great. Thanks.

I've gotten this before. My problem was that I had a cached UIImage that I loaded with UIImage +imageNamed and forgot to retain -- it stayed active because it got stored in the cache, but apparently, going to the background seemed to "clear" it, so when I came back from the background my code ended up trying to use something that wasn't there anymore. I just had to add a retain after loading the image, and it was fixed (with no leaks reported by instruments).

I dunno if this is anywhere near your problem, but you asked if anyone else has experienced a similar issue.