从TabBarController的导航控制器中隐藏BarButton项

Question

I have a tabBarController that contains three tabs. I want to show rightBarButtonItem to navigation bar only in 1st ViewController but when i am getting back i want it to be visible again. How to achieve this?

I tried to set enabled=NO for the BarButtonItem but the result wasn't good.

I also tried to set BarButtonItem to nil when the view changes but when i get back has disappeared.

I moved BarButtonItem from viewDidLoad to viewWillAppear but it did't work properly.

This is the code for rightBarButtonItem into viewDidLoad of first ViewController.

UIImage *refreshButtonImage = [UIImage imageNamed:@"9B_Info.png"];
UIImage *refreshButtonImageB = [UIImage imageNamed:@"9A_Info.png"];

UIButton *refreshButton = [UIButton buttonWithType:UIButtonTypeCustom];

[refreshButton setImage:refreshButtonImage
               forState:UIControlStateNormal];

[refreshButton setImage:refreshButtonImageB
               forState:UIControlStateHighlighted];

[refreshButton setImage:refreshButtonImageB
               forState:UIControlStateSelected];

refreshButton.frame = CGRectMake(0, 0, 30, 30);

[refreshButton addTarget:self
                  action:@selector(showImageInfo)
        forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *refreshBarButtonItem = [[UIBarButtonItem alloc]  initWithCustomView:refreshButton];

self.refreshBtn=refreshBarButtonItem;

[self.tabBarController.navigationItem setRightBarButtonItem:self.refreshBtn];

Answer 1

Do you use storyboard or all in programmatic way ? Try this:

1- open new project ( single view )

2- go into storyboard -> add a navigation controller

3- delete the table view controller

4- set your navigation controller as the start controller ( drag the arrow which points your view controller to your navigation controller )

5- set your view controller as the root view controller of your navigation controller

6- complete with your codes and @Apurv's solution bellow

Answer 2

Replace your below line:

[self.tabBarController.navigationItem setRightBarButtonItem:self.refreshBtn];

With this line:

[self.navigationItem setRightBarButtonItem:self.refreshBtn];

When you want to display it for viewController only, do not add it to tabBarController.

Answer 3

If anyone comes up with this in future this worked for me:

In first view controller i added this to viewWillAppear

- (void)viewWillAppear:(BOOL)animated
{
   [super viewWillAppear:animated];

    NSLog(@"!!!!");

    UIImage *refreshButtonImage = [UIImage imageNamed:@"9B_Info.png"];
    UIImage *refreshButtonImageB = [UIImage imageNamed:@"9A_Info.png"];

    UIButton *refreshButton = [UIButton buttonWithType:UIButtonTypeCustom];

    [refreshButton setImage:refreshButtonImage
                forState:UIControlStateNormal];

    [refreshButton setImage:refreshButtonImageB
                forState:UIControlStateHighlighted];

    [refreshButton setImage:refreshButtonImageB
                forState:UIControlStateSelected];

    refreshButton.frame = CGRectMake(0, 0, 30, 30);

    [refreshButton addTarget:self
                   action:@selector(showImageInfo)
         forControlEvents:UIControlEventTouchUpInside];

    UIBarButtonItem *refreshBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:refreshButton];

    self.refreshBtn=refreshBarButtonItem;

    [self.tabBarController.navigationItem setRightBarButtonItem:self.refreshBtn];



}

And in second View Controller in viewWillAppear method this:

    self.tabBarController.navigationItem.rightBarButtonItem=nil;

The problem is that viewDidLoad of each viewController into TabBarController is called only once but viewWillAppear every time that viewController comes up.