Making a view behind iOS 7 status bar

UIViewController.m

- (void)viewDidLoad
{
    CGRect rect = CGRectMake(0, 0, self.view.frame.size.width, 20);
    UIView *statusBarBg = [[UIView alloc] initWithFrame:rect];
    [self.view addSubview:statusBarBg];
    statusBarBg.backgroundColor = [UIColor purpleColor];
}