Tengo un error extraño con un rightBarButtomItem personalizado en la barra de navegación. Tengo una aplicación TabBar. Si la aplicación está cargada, el botón se muestra correcto. Si hago clic en las pestañas, el botón sigue apareciendo. Si vuelvo a una de las pestañas que ya se mostró, el botón desaparece. Al final, el botón solo se muestra al azar en una de las pestañas.

Mi código funciona a la perfección si configuro programáticamente un rightBarButtomItem estándar. Pero no con gráficos personalizados. Si se presiona un ChildViewController y se abre el botón aparece nuevamente. ¡Parece que todavía está allí pero no es visible!

¡Creo que mi referencia de sharedRightButton dentro del CustomTabBarViewController es incorrecta!

¿Alguien puede ayudar?

CustomTabBarController.h

   #import <UIKit/UIKit.h>
    #import "EZBadgeView.h"

    @interface CustomTabBarController : UITabBarController
    {
        EZBadgeView *badgeView;
        UIButton *btn;
        UIImage *rightBarButtonItemImage;
        UIImage *rightBarButtonItemImageTapped;
        UIImage *rightBarButtonItemImageSelected;
    }

    @property (nonatomic, strong) UIBarButtonItem *sharedRightButton;
    @property (nonatomic, strong) EZBadgeView *badgeView;
    @property(nonatomic, strong) UIButton *btn;
    @property(nonatomic, strong) UIImage *rightBarButtonItemImage;
    @property(nonatomic, strong) UIImage *rightBarButtonItemImageTapped;
    @property(nonatomic, strong) UIImage *rightBarButtonItemImageSelected;

    @end

CustomTabBarController.m

    #import "CustomTabBarController.h"

    @interface CustomTabBarController ()

    @end

    @implementation CustomTabBarController

    @synthesize sharedRightButton, badgeView, btn, rightBarButtonItemImage, rightBarButtonItemImageSelected, rightBarButtonItemImageTapped;

    - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
    {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
            // Custom initialization
        }
        return self;
    }

    - (void)viewDidLoad
    {
        [super viewDidLoad];

        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(updateBadgeNumber:) name:@"updateBadgeNumber" object:nil];

        if (self.badgeView && self.badgeView.superview)
        {
            [self.badgeView removeFromSuperview];
        }
        self.badgeView = [[EZBadgeView alloc] init];
        CGRect badgeFrame = self.badgeView.frame;
        badgeFrame.origin.x = 31.0f;
        badgeFrame.origin.y = -6.0f;
        badgeFrame = CGRectIntegral(badgeFrame);
        self.badgeView.frame = badgeFrame;
        self.badgeView.badgeBackgroundColor = [self colorWithRGBHex:kRed withAlpha:1.0f];
        self.badgeView.userInteractionEnabled = NO;
        self.badgeView.badgeTextFont = [UIFont fontWithName:@"BrownStd-Bold" size:12];
        self.badgeView.shouldShowGradient = NO;
        self.badgeView.shouldShowShine = NO;

        // Allocate UIButton
        self.btn = [UIButton  buttonWithType:UIButtonTypeCustom];
        self.btn.frame = CGRectMake(0, 0, 46, 30);

        self.rightBarButtonItemImage = [UIImage imageNamed:@"button_mixer.png"];
        [self.btn setBackgroundImage:rightBarButtonItemImage forState:UIControlStateNormal];
        self.rightBarButtonItemImageTapped = [UIImage imageNamed:@"button_mixer_pressed.png"];
        [self.btn setBackgroundImage:rightBarButtonItemImageTapped forState:UIControlStateHighlighted];
        self.rightBarButtonItemImageSelected = [UIImage imageNamed:@"button_mixer_active.png"];
        [self.btn setBackgroundImage:rightBarButtonItemImageSelected forState:UIControlStateSelected];

        [self.btn addTarget:self action:@selector(clickedTest:) forControlEvents:UIControlEventTouchUpInside];
        [self.btn setBackgroundColor:[UIColor clearColor]];
        [self.btn addSubview:self.badgeView]; //Add NKNumberBadgeView as a subview on UIButton

        // Initialize UIBarbuttonitem...
         self.sharedRightButton = [[UIBarButtonItem alloc] initWithCustomView:btn];
         self.badgeView.badgeValue = @"0";
         self.badgeView.hidden = YES;
    }

    - (void)updateBadgeNumber:(NSMutableArray *)soundArray
    {
        self.badgeView.badgeValue = [NSString stringWithFormat:@"%i",[soundArray count]];
        self.badgeView.hidden = ([soundArray count] == 0);
    }

    - (void)clickedTest:(id)sender
    {
        NSLog(@"%s", __FUNCTION__);
    }

    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }

    - (UIColor *)colorWithRGBHex:(UInt32)hex withAlpha:(float)alpha
    {
        int r = (hex >> 16) & 0xFF;
        int g = (hex >> 8) & 0xFF;
        int b = (hex) & 0xFF;

        return [UIColor colorWithRed:r / 255.0f
                               green:g / 255.0f
                                blue:b / 255.0f
                               alpha:alpha];
    }

    @end

Y configuro el botón así en cada vista:

@implementation MyVC

@synthesize tabBarController;

    - (void)viewDidLoad
    {
        //NSLog(@"begin: %s", __FUNCTION__);
        [super viewDidLoad];


         // right bar button from custom tabbarcontroller
        self.tabBarController = [[CustomTabBarController alloc] init];
        self.navigationItem.rightBarButtonItem = self.tabBarController.sharedRightButton;

}