Repeating background image in native iPhone app – Stack Overflow

Apparently a UIColor is not necessarily a single color, but can be a pattern as well. Confusingly, this is not supported in Interface Builder.

Instead you set the backgroundColor of the view (say, in -viewDidLoad) with the convenience method +colorWithPatternImage: and pass it a UI Image. For Instance:

- (void)viewDidLoad {
  [super viewDidLoad];
  self.view.backgroundColor =
    [UIColor colorWithPatternImage:
       [UIImage imageNamed:@"gingham.png"]];
}

Of course, don’t forget to add the image file to your application bundle.

via Repeating background image in native iPhone app – Stack Overflow.