title: navigation title on previous screen disappear when back button pressed
body: <p>i have a problem with navigation bar title. i have 2 screen, when i click back button on screen 2 it will back to screen 1 but the title of screen 1 is disappear. Here is my snippet code</p>
  
  <p>screen1 .m</p>
  
  <pre><code>    - (void)viewDidLoad
  {
      [super viewDidLoad];
      // Do any additional setup after loading the view.
  
      self.title = @"title 1";
  ....
  </code></pre>
  
  <p>screen 2 .m</p>
  
  <pre><code>- (void)viewDidLoad
  {
      [super viewDidLoad];
      // Do any additional setup after loading the view.
  
      self.title = self.stringTitle;
  
      // change the back button and add an event handler
      self.navigationItem.hidesBackButton = YES;
      //set custom image to button if needed
      UIImage *backButtonImage = [UIImage imageNamed:@"btn_back.png"];
      UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
      [button setImage:backButtonImage forState:UIControlStateNormal];
      button.frame = CGRectMake(-12, 2, backButtonImage.size.width, backButtonImage.size.height);
      [button addTarget:self action:@selector(backAction) forControlEvents:UIControlEventTouchUpInside];
  
      UIView *backButtonView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, backButtonImage.size.width-15, backButtonImage.size.height)];
      [backButtonView addSubview:button];
  
      UIBarButtonItem *customBarItem = [[UIBarButtonItem alloc] initWithCustomView:backButtonView];
      self.navigationItem.leftBarButtonItem = customBarItem;
  
      self.navigationController.navigationBar.titleTextAttributes = @{NSForegroundColorAttributeName: [UIColor whiteColor]};
  ....
  }
  
  - (void) backAction
  {
      [self.navigationController popViewControllerAnimated:YES];
  }
  </code></pre>
  
  <p>i've tried several tricks to make title of screen 1 appears with the following tricks:</p>
  
  <ol>
  <li><p>set title on <code>viewwillappear</code> method</p>
  
  <pre><code>- (void)viewWillAppear:(BOOL)animated{self.title = @"tes";}
  </code></pre></li>
  <li><p>set title on <code>viewdidappear</code> method</p>
  
  <pre><code> - (void)viewDidAppear:(BOOL)animated{
   self.navigationController.navigationBar.topItem.title = @"YourTitle";
    self.title = @"tes";
    }
  </code></pre></li>
  </ol>
  
  <p>but the title is still disappears. please help</p>
  
  <hr>
  
  <p>here is the way how i moving to next screen</p>
  
  <pre><code>- (IBAction)btGenerateTokenAction:(id)sender {
      SofttokenResultController *controller = [[SofttokenResultController alloc] initWithNibName:@"SofttokenResultController" bundle:nil];
  
      controller.navigationController.navigationBar.backItem.title = @"Kembali";
      [ViewLoadingUtil animateToNextView:controller from:self :@""];
  }
  
  + (void) animateToNextView:(UIViewController *)controller from:(UIViewController *)fromController :(NSString *)navTitle{
  
      NSLog(@"animateToNextView called");
  
      [fromController.navigationController pushViewController:controller animated:YES];
  }
  </code></pre>