UIButButtonItem与UIButton作为自定义视图不会显示

Question

I am trying to display a custom UIButton as a UINavigationItem 's rightBarButtonItem .
I wrote the following code:

UIButton *inviteButton = [UIButton buttonWithType:UIButtonTypeCustom];
[inviteButton setTitle:@"Invite" forState:UIControlStateNormal];
inviteButton.frame = CGRectMake(0, 0, 30, 30);
inviteButton.backgroundColor = [UIColor redColor];
inviteButton.layer.borderColor = [UIColor blueColor].CGColor;
inviteButton.layer.borderWidth = 1.0f;

UIBarButtonItem *inviteButtonContainer = [[UIBarButtonItem alloc] initWithCustomView:inviteButton];

viewController.navigationItem.rightBarButtonItem = inviteButtonContainer;

Nothing shows up in my navigation bar.

However, with the following code, I can see a basic button:

UIBarButtonItem *inviteButton = [[UIBarButtonItem alloc] initWithTitle:@"Invite"
                                                                 style:UIBarButtonItemStyleDone
                                                                target:self
                                                                action:nil];

viewController.navigationItem.rightBarButtonItem = inviteButton;

But it's obviously not what I am after, since I am looking to play with the button appearance.


Edit
I was trying to add the same instance of UIBarButtonItem ( inviteButtonContainer ) to many navigation bars. Doing that, it's visible on the last navigation bar only.
However, if I use the same instance of a simple UIBarButtonItem (without custom view), it's displayed on every navigation bars. Any idea why?

Answer 1

Your code is fine, just change this line:

    viewController.navigationItem.rightBarButtonItem = inviteButtonContainer;

to

    self.navigationItem.rightBarButtonItem = inviteButtonContainer;

From the Documentation:

The navigation item used to represent the view controller in a parent's navigation bar.

self itself represents that it belongs to view controller , so there is no need to mention the view controller instance to add the navigation item.

Answer 2

-> To display custom button in a view controller in which custom bar button is crated (ie in self) :

- (void)viewDidLoad {
    [super viewDidLoad];

    UIButton *inviteButton = [UIButton buttonWithType:UIButtonTypeCustom];
    [inviteButton setTitle:@"Invite" forState:UIControlStateNormal];
    inviteButton.frame = CGRectMake(0, 0, 70, 30);
    inviteButton.backgroundColor = [UIColor redColor];
    inviteButton.layer.borderColor = [UIColor blueColor].CGColor;
    inviteButton.layer.borderWidth = 1.0f;

    UIBarButtonItem *inviteButtonContainer = [[UIBarButtonItem alloc] initWithCustomView:inviteButton];

    controller.navigationItem.rightBarButtonItem = inviteButtonContainer;
}

-> To display custom bar button in a view controller that is about to present

eg. To display a view controller after a cell is selected in table view

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    DjDetailsViewController *controller = (DjDetailsViewController *) 
    [self.storyboard instantiateViewControllerWithIdentifier:@"DjDetailsViewController"];

    UIButton *inviteButton = [UIButton buttonWithType:UIButtonTypeCustom];
    [inviteButton setTitle:@"Invite" forState:UIControlStateNormal];
    inviteButton.frame = CGRectMake(0, 0, 70, 30);
    inviteButton.backgroundColor = [UIColor redColor];
    inviteButton.layer.borderColor = [UIColor blueColor].CGColor;
    inviteButton.layer.borderWidth = 1.0f;

    UIBarButtonItem *inviteButtonContainer = [[UIBarButtonItem alloc] initWithCustomView:inviteButton];

    controller.navigationItem.rightBarButtonItem = inviteButtonContainer;
    [self.navigationController pushViewController:controller animated:YES];
}

I didn't done major. I just used your code and change frame of custom bar button. I hope this will help you.

Answer 3

You issue is with your invite button initialiser:

UIButton *inviteButton = [UIButton UIButtonTypeCustom];

UIButtonTypeCustom is an enum value not a class method/convenience constructor.

use

UIButton *inviteButton = [UIButton buttonWithType:UIButtonTypeCustom];

Hope this helps