DJPAppDelegate.h

@interface DJPAppDelegate : UIResponder <UIApplicationDelegate, UIAppearanceContainer>

@end

DJPAppDelegate.m

@implementation UINavigationBar (UINavigationBarCategory)
- (void)drawRect:(CGRect)rect {
    UIColor *color = [UIColor redColor];
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColor(context, CGColorGetComponents( [color CGColor]));
    CGContextFillRect(context, rect);
}
@end


@implementation DJPAppDelegate
// missing code
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
    // Override point for customization after application launch.

    DJPMasterViewController *masterViewController = [[[DJPMasterViewController alloc] initWithNibName:@"DJPMasterViewController" bundle:nil] autorelease];

    self.navigationController = [[[UINavigationController alloc] initWithRootViewController:masterViewController] autorelease];

    self.window.rootViewController = self.navigationController;
    [self.window makeKeyAndVisible];
    
    if([UINavigationBar respondsToSelector:@selector(appearance)]){
        UIImage *image = [UIImage imageNamed:@"bg.png"];
        [[UINavigationBar appearance] setBackgroundImage:image forBarMetrics:UIBarMetricsDefault];
    }

    return YES;
}

//Instead of creating image from existing image. we can create it dynamically
//
- (UIImage *)imageWithColor:(UIColor *)color andSize:(CGSize)size {
  //Create a context of the appropriate size
  UIGraphicsBeginImageContext(size);
  CGContextRef currentContext = UIGraphicsGetCurrentContext();

  //Build a rect of appropriate size at origin 0,0
  CGRect fillRect = CGRectMake(0,0,size.width,size.height);

  //Set the fill color
  CGContextSetFillColorWithColor(currentContext, color.CGColor);

  //Fill the color
  CGContextFillRect(currentContext, fillRect);

  //Snap the picture and close the context
  UIImage *retval = UIGraphicsGetImageFromCurrentImageContext(void);
  UIGraphicsEndImageContext();

  return retval;
}

// missing code
@end