Question

Im trying to use this tab bar view controller but am having difficulties getting it to load my view controllers.

I have followed their demo filling in my view controllers for theirs but all I get are black views (probably nil?). I have setup a breakpoint and the self.tabBarItems is filled with my view controllers from the best I can tell. Meaning that if I give it 2 view controllers the count is two but I am unable to see further details:

see how tabBarItems has 2 objects but that even with the drop down arrow clicked nothing is listed?

Anyways the code is pretty simple.

My code:

- (void)setup {

  // Set View Frame
    self.viewFrame = (CGRect){CGPointZero, {kKYViewWidth, kKYViewHeight}};

    // Add child view controllers to each tab
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {

        _salesViewController  = [[SalesViewController alloc] initWithNibName:@"SalesViewController_iPhone" bundle:nil];

        _customersViewController = [[CustomersViewController alloc] initWithNibName:@"CustomersViewController_iPhone" bundle:nil];

        _itemsViewController = [[ItemsViewController alloc] initWithNibName:@"ItemsViewController_iPhone" bundle:nil];

        _employeesViewController = [[EmployeesViewController alloc] initWithNibName:@"EmployeesViewController_iPhone" bundle:nil];

        _settingsViewController = [[SettingsViewController alloc] initWithNibName:@"SettingsViewController_iPhone" bundle:nil];

    } else {

        _salesViewController  = [[SalesViewController alloc] initWithNibName:@"SalesViewController_iPad" bundle:nil];

        _customersViewController = [[CustomersViewController alloc] initWithNibName:@"CustomersViewController_iPad" bundle:nil];

        _itemsViewController = [[ItemsViewController alloc] initWithNibName:@"ItemsViewController_iPad" bundle:nil];

        _employeesViewController = [[EmployeesViewController alloc] initWithNibName:@"EmployeesViewController_iPad" bundle:nil];

        _settingsViewController = [[SettingsViewController alloc] initWithNibName:@"SettingsViewController_iPad" bundle:nil];
    }

  // Set child views' Frame
    CGRect childViewFrame = self.viewFrame;
    [_salesViewController.view   setFrame:childViewFrame];
    [_customersViewController.view   setFrame:childViewFrame];
    [_itemsViewController.view setFrame:childViewFrame];
    [_employeesViewController.view  setFrame:childViewFrame];
    [_settingsViewController.view  setFrame:childViewFrame];

  // Add child views as tab bar items
  self.tabBarItems = @[@{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 1],
                         @"Sales" : _salesViewController} ,
                       @{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 2],
                        @"Customers" : _customersViewController}
    ];

  // Add a gesture signal on the first view
  UIImage * gestureImage = [UIImage imageNamed:kKYIArcTabGestureHelp];
  CGRect gestureImageViewFrame =
    (CGRect){{(kKYViewWidth - gestureImage.size.width) / 2.f,
              (kKYViewHeight - kKYTabBarHeight - gestureImage.size.height) / 2.f},
             gestureImage.size};
  UIImageView * gestureImageView = [[UIImageView alloc] initWithFrame:gestureImageViewFrame];
  [gestureImageView setImage:gestureImage];
  [gestureImageView setUserInteractionEnabled:YES];
  [_salesViewController.view addSubview:gestureImageView];
}

demo’s code which does work If I swap it in:

// Override |KYArcTabViewController|'s |-setup|
- (void)setup {
  // Set View Frame
  self.viewFrame = (CGRect){CGPointZero, {kKYViewWidth, kKYViewHeight}};

  // Add child view controllers to each tab
  viewControllerOne_   = [[UIViewController alloc] init];
  viewControllerTwo_   = [[UIViewController alloc] init];
  viewControllerThree_ = [[UIViewController alloc] init];
  viewControllerFour_  = [[UIViewController alloc] init];

  // Set child views' Frame
  CGRect childViewFrame = self.viewFrame;
  [viewControllerOne_.view   setFrame:childViewFrame];
  [viewControllerTwo_.view   setFrame:childViewFrame];
  [viewControllerThree_.view setFrame:childViewFrame];
  [viewControllerFour_.view  setFrame:childViewFrame];

  // Set child views' background color
  [viewControllerOne_.view   setBackgroundColor:[UIColor blackColor]];
  [viewControllerTwo_.view   setBackgroundColor:[UIColor redColor]];
  [viewControllerThree_.view setBackgroundColor:[UIColor greenColor]];
  [viewControllerFour_.view  setBackgroundColor:[UIColor blueColor]];

  // Add child views as tab bar items
  self.tabBarItems = @[@{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 1],
                         @"viewController" : viewControllerOne_},
                       @{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 2],
                         @"viewController" : viewControllerTwo_},
                       @{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 3],
                         @"viewController" : viewControllerThree_},
                       @{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 4],
                         @"viewController" : viewControllerFour_}];

  // Add a gesture signal on the first view
  UIImage * gestureImage = [UIImage imageNamed:kKYIArcTabGestureHelp];
  CGRect gestureImageViewFrame =
    (CGRect){{(kKYViewWidth - gestureImage.size.width) / 2.f,
              (kKYViewHeight - kKYTabBarHeight - gestureImage.size.height) / 2.f},
             gestureImage.size};
  UIImageView * gestureImageView = [[UIImageView alloc] initWithFrame:gestureImageViewFrame];
  [gestureImageView setImage:gestureImage];
  [gestureImageView setUserInteractionEnabled:YES];
  [viewControllerOne_.view addSubview:gestureImageView];
  [gestureImageView release];
}

FYI: few things left out of the demo’s code which is just basic stuff like declaring the properties, init and synthesizing (nothing special though). Also I have tried with and without using the accessors (self. vs _var)

So basically Im wondering why my customer view controllers dont get loaded? Like I said I just get black screens (behind the tab bar).

Answer 1

So the problem was that

self.tabBarItems = @[@{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 1],
                         @"viewController" : viewControllerOne_},
                       @{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 2],
                         @"viewController" : viewControllerTwo_},
                       @{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 3],
                         @"viewController" : viewControllerThree_},
                       @{@"image"          : [NSString stringWithFormat:kKYITabBarItemImageNameFormat, 4],
                         @"viewController" : viewControllerFour_}];

Needed the word “viewController” not the name of the view controller. this was a key that the parent class was using to retrieve the views.