Question

I have a need to use a custom background for the UINavigationBar in a MFMailComposeViewController. Previously I was using a category on UINavigationBar to achieve this throughout my app, but Apple specifically requests that you do not do this. Additionally this may or may not work in future versions of iOS that are currently under NDA.

I am now using a subclass of UINavigationBar to achieve the look I’m after in the rest of the app, but I can’t see any way to use this with the MFMailComposeViewController. Any ideas?

Note: I’m aware of methods to do this in a future version of iOS, but this needs to be built against a current version (4.3) of the SDK.

Answer 1

I just ran across this — you can dynamically inject the class a view controller uses using object_setClass.

#import <objc/runtime.h>

object_setClass(mailController.navigationBar, [YourNavigationBarSubClass class]);