Compiling an app that works in iOS 6 and iOS 7

Question

I'm struggling to compile an iPad app for use on iOS 6 and iOS 7. Here's the message I keep getting: ``` Property 'barTintColor' not found on object of type 'UITabBar *'; did you mean 'tintColor'? ``` The `Base SDK` for the target is set to `Latest iOS (iOS 7.0)`, and the `iOS Deployment Target` is `iOS 6.0`. I did a Clean on the project. Here is the code: In the .h file: ``` @property (nonatomic, strong) IBOutlet UITabBar *tabbedBar; ``` In the .m file: ``` if ([tabbedBar respondsToSelector: @selector(barTintColor)]) { tabbedBar.barTintColor = [UIColor blackColor]; } ``` I'm compiling against the iOS 7 SDK, so it should know about barTintColor. Any idea what the problem could be? Updated: Okay, I'm making progress, but not quite understanding why. See this Xcode screenshot. Note the two entries for my iPad 3 in the Active Scheme selection. What is the difference? If I choose the top option, I get the error. If I choose the bottom option, it works. Can anyone explain why the same devi…

Accepted Answer

You have two SDKs installed in your Xcode: for iOS 6 and iOS 7. Now, when that happens, if you plug in your iOS 7 device, it shows as two devices (i.e. options) in the device selector: first row is for iPad 3 (iOS 6), second for iPad 3 (iOS 7).

The problem with your error is that when you select iPad 3 (iOS 6), Xcode still reads the device as iOS 7 (and that's what it has installed, anyway) so when building it passes the `[tabbedBar respondsToSelector: @selector(barTintColor)]` code (it responds to the selector, 'cause hey, it's iOS 7), but because you're building for iOS 6, at the same time it raises an error, 'cause hey, iOS 6 doesn't have that method! Fun.

Basically, you can't use the iOS 6 option when testing on the iOS 7 device. You either need a iOS 6 device, or you're stuck with the simulator for testing old versions.

EDIT: You can test what I'm saying in the following manner — instead of using `respondsToSelector:` use

```
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0f) {
    // code
}
```

and then select the first device in the list (iPad 3 iOS 6). You'll see that you go through the `if` clause, but Xcode gives you an error that the selector isn't available on iOS 6.

Compiling an app that works in iOS 6 and iOS 7

Solution

Problem