Adding background for window is not working

问题

I have this code which run very well on XCode 4 / iOS 6 to add background image on window :

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"bgleft"]];
    return YES;

}

but today, when I try to put it into XCode 5 and try to build an app for iOS 7, it's not working anymore. is there something changed from XCode 4 to XCode 5?

thank you.

回答1:

Try adding a controller to your window:

UIViewController *controller = [[UIViewController alloc] init];
controller.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"bgleft"]]; // (the error may be here, where's the extension for the image? ".png" for example
self.window.rootViewController = controller;
[self.window makeKeyAndVisible];
return YES;

And make sure the images extension is included within your code, and is also imported into the xcode project

Also if you're deploying on a retina display device, the image needs to include @2x after the name and before the extension, like so:

bgleft@2x.png

来源：https://stackoverflow.com/questions/18908836/adding-background-for-window-is-not-working