IOS 5 unrecognized selector send at appearance proxy for setBackgroundImage

Like a lot of developers I am playing around with the new features of IOS 5.

I tried to use appearance proxy's for customizing my App. But at some methods I get an error.

This w开发者_运维技巧orks:

[[UINavigationBar appearance] setBarStyle:UIBarStyleBlackTranslucent];
//and
[[UINavigationBar appearance] setTintColor:[UIColor greenColor]];

But when I try:

[[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:@"toolbar_background.png"]];

I get an unrecognized selector error:

-[_UIAppearance setBackgroundImage:]: unrecognized selector sent to instance 0x153020
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[_UIAppearance setBackgroundImage:]: unrecognized selector sent to instance 0x153020'
*** First throw call stack:
(0x3107a8bf 0x3821f1e5 0x3107dacb 0x3107c945 0x30fd7680 0x2fe7 0x3304c7eb 0x330463bd 0x33014921 0x330143bf 0x33013d2d 0x33bffe13 0x3104e553 0x3104e4f5 0x3104d343 0x30fd04dd 0x30fd03a5 0x33045457 0x33042743 0x2f31 0x2ec8)
terminate called throwing an exception(gdb) 

Any ideas ?

The method has a different name, you're missing a part of it. Since iOS 5 is still under NDA, I won't cite or link the method name here, but you can look it up yourself:

• Go to the iOS Dev Center.
• Select iOS SDK GM Seed.
• Select iOS Developer Library.
• In the search field, start typing UINavigationBar.
• Click on the UINavigationBar Class Reference link.
• Read the documentation.