iPhone: Icon extension error in the archive validation

Question

Using the Xcode 3.2.3 I updated my app to iOS4 and build an archive. When I tried to validate the application I received these warnings:

"Icon specified in the Info.plist CFBundleIconFile does not have an extension: icon"

Since my app is a universal app I have 4 icons mentioned in the plist and therefore 4 errors. I will also point out that in my plist the icons appear under CFBundleIconFiles and not CFBundleIconFile.

It is a known fact that it is better not to write the extensions of the icons otherwise the automatic retina display image choosing mechanism won't kick in and take the proper iPhone4 @2x icons.

What am I missing here?

Answer 1

Solution here (mostly):

http://useyourloaf.com/blog/2010/8/4/application-icon-troubles.html

However, he was wrong on one point: in addition to the CFBundleIconFiles array, you still do need a CFBundleIconFile key with just the name of the 57x57 png file in it (e.g. just icon.png) in order to support backwards compatibility with pre-iOS4 devices. Otherwise, Application Loader will be a bitch and refuse to let you upload it.

Answer 2

You should write file extensions, @2x images are loaded automatically with- or without extension.