UINavigationBar multi-line title

Question

Set the titleView property of the UINavigationItem. For example, in the view controller's viewDidLoad method you could do something like:

UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 480, 44)];
label.backgroundColor = [UIColor clearColor];
label.numberOfLines = 2;
label.font = [UIFont boldSystemFontOfSize: 14.0f];
label.shadowColor = [UIColor colorWithWhite:0.0 alpha:0.5];
label.textAlignment = UITextAlignmentCenter;
label.textColor = [UIColor whiteColor];
label.text = @"This is a\nmultiline string";

self.navigationItem.titleView = label;

#if !__has_feature(objc_arc)
[label release];
#endif

It shows up like this:

Remember the titleView property is ignored if leftBarButtonItem is not nil.

for Swift:

let label = UILabel(frame: CGRectMake(0, 0, UIScreen.main.bounds.width, 44))
label.backgroundColor = UIColor.clearColor()
label.numberOfLines = 0
label.textAlignment = NSTextAlignment.Center
label.text = "multiline string"
self.navigationItem.titleView = label

for swift 4:

    let label = UILabel(frame: CGRect(x: 0.0, y: 0.0, width: UIScreen.main.bounds.width, height: 44.0))
    label.backgroundColor = UIColor.clear
    label.numberOfLines = 0
    label.textAlignment = NSTextAlignment.center
    label.text = "first line\nsecond line"
    self.navigationItem.titleView = label   

Swift solution:

2 lines in NavigationBar:

private func setupTitleView() {
    let topText = NSLocalizedString("key", comment: "")
    let bottomText = NSLocalizedString("key", comment: "")

    let titleParameters = [NSForegroundColorAttributeName : UIColor.<Color>(),
                           NSFontAttributeName : UIFont.<Font>]
    let subtitleParameters = [NSForegroundColorAttributeName : UIColor.<Color>(),
                              NSFontAttributeName : UIFont.<Font>]

    let title:NSMutableAttributedString = NSMutableAttributedString(string: topText, attributes: titleParameters)
    let subtitle:NSAttributedString = NSAttributedString(string: bottomText, attributes: subtitleParameters)

    title.appendAttributedString(NSAttributedString(string: "\n"))
    title.appendAttributedString(subtitle)

    let size = title.size()

    let width = size.width
    guard let height = navigationController?.navigationBar.frame.size.height else {return}

    let titleLabel = UILabel(frame: CGRectMake(0,0, width, height))
    titleLabel.attributedText = title
    titleLabel.numberOfLines = 0
    titleLabel.textAlignment = .Center

    navigationItem.titleView = titleLabel
}

2 line in BarButton

    let string = NSLocalizedString("key", comment: "")
    let attributes = [NSForegroundColorAttributeName : UIColor.<Color>,
                      NSFontAttributeName : UIFont.<Font>]
    let size = (string as NSString).sizeWithAttributes(attributes)
    guard let height = navigationController?.navigationBar.frame.size.height else {return}
    let button:UIButton = UIButton(frame: CGRectMake(0, 0, size.width, height))
    button.setAttributedTitle(NSAttributedString(string: string, attributes: attributes), forState: .Normal)
    button.addTarget(self, action: #selector(<SELECTOR>), forControlEvents: .TouchUpInside)
    button.titleLabel?.numberOfLines = 0
    button.titleLabel?.textAlignment = .Right
    let rightBarButton = UIBarButtonItem(customView: button)
    navigationItem.rightBarButtonItem = rightBarButton

result -

After a lot of tweaking, I still couldn't get petert's solution to work for me in iOS 8. Here's a copy-paste-able solution for iOS 8/9. Credit goes to Matt Curtis's github post

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

    if(!self.navigationItem.titleView){
        self.navigationItem.titleView = ({
            UILabel *titleView = [UILabel new];
            titleView.numberOfLines = 0;
            titleView.textAlignment = NSTextAlignmentCenter;
            titleView.attributedText = [[NSAttributedString alloc] initWithString:@"2\nLINES" attributes:
                self.navigationController.navigationBar.titleTextAttributes
            ];

            [titleView sizeToFit];
            // You'll need to set your frame otherwise if your line breaks aren't explcit.

            titleView;
        });
    }
}

What to do when label is not centered

If you encounter same issue as me - that label is not centered in navigationItem because of back button, embed your UILabel to UIView. UILabel is then not forced to grow with it's text, but stop growing when it's width raise view's width. More about this issue you can find here: Can't set titleView in the center of navigation bar because back button ( Darren's answer )

Not centered:

- (void)setTwoLineTitle:(NSString *)titleText color:(UIColor *)color font:(UIFont *)font {
    CGFloat titleLabelWidth = [UIScreen mainScreen].bounds.size.width/2;

    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, titleLabelWidth, 44)];
    label.backgroundColor = [UIColor clearColor];
    label.numberOfLines = 2;
    label.font = font;
    label.adjustsFontSizeToFitWidth = YES;
    label.textAlignment = UITextAlignmentCenter;
    label.textColor = color;
    label.text = titleText;

    self.navigationItem.titleView = label;
}

Centered:

- (void)setTwoLineTitle:(NSString *)titleText color:(UIColor *)color font:(UIFont *)font {
    CGFloat titleLabelWidth = [UIScreen mainScreen].bounds.size.width/2;

    UIView *wrapperView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, titleLabelWidth, 44)];

    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, titleLabelWidth, 44)];
    label.backgroundColor = [UIColor clearColor];
    label.numberOfLines = 2;
    label.font = font;
    label.adjustsFontSizeToFitWidth = YES;
    label.textAlignment = UITextAlignmentCenter;
    label.textColor = color;
    label.text = titleText;

    [wrapperView addSubview:label];

    self.navigationItem.titleView = wrapperView;
}

Here is a Swift 3 version of handling a multiline title:

override func viewDidLoad() {
    super.viewDidLoad()

    let label = UILabel(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 44))
    label.backgroundColor = .clear
    label.numberOfLines = 0
    label.textAlignment = .center
    label.font = UIFont.boldSystemFont(ofSize: 14.0)
    label.text = "This is a Multi-Line title of UINavigationBar"
    self.navigationItem.titleView = label
}