简体   繁体   中英

How to add a button to UINavigationBar?

如何以编程方式向UINavigationBar添加按钮?

Sample code to set the rightbutton on a NavigationBar .

UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithTitle:@"Done" 
    style:UIBarButtonItemStyleDone target:nil action:nil];
UINavigationItem *item = [[UINavigationItem alloc] initWithTitle:@"Title"];
item.rightBarButtonItem = rightButton;
item.hidesBackButton = YES;
[bar pushNavigationItem:item animated:NO];

But normally you would have a NavigationController , enabling you to write:

UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithTitle:@"Done"
    style:UIBarButtonItemStyleDone target:nil action:nil];
self.navigationItem.rightBarButtonItem = rightButton;

The answers above are good, but I'd like to flesh them out with a few more tips:

If you want to modify the title of the back button (the arrow-y looking one at the left of the navigation bar) you MUST do it in the PREVIOUS view controller, not the one for which it will display. It's like saying "hey, if you ever push another view controller on top of this one, call the back button "Back" (or whatever) instead of the default."

If you want to hide the back button during a special state, such as while a UIPickerView is displayed, use self.navigationItem.hidesBackButton = YES; and remember to set it back when you leave the special state.

If you want to display one of the special symbolic buttons, use the form initWithBarButtonSystemItem:target:action with a value like UIBarButtonSystemItemAdd

Remember, the meaning of that symbol is up to you, but be careful of the Human Interface Guidelines. Using UIBarButtonSystemItemAdd to mean deleting an item will probably get your application rejected.

Adding custom button to navigation bar ( with image for buttonItem and specifying action method (void)openView{} and).

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0, 0, 32, 32);
[button setImage:[UIImage imageNamed:@"settings_b.png"] forState:UIControlStateNormal];
[button addTarget:self action:@selector(openView) forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *barButton=[[UIBarButtonItem alloc] init];
[barButton setCustomView:button];
self.navigationItem.rightBarButtonItem=barButton;

[button release];
[barButton release];

The example below will display a button with a title "Contact" on the navigation bar on the right. Its action calls a method named "contact" from the viewcontroller. Without this line the right button is not visible.

    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Contact"
                                                                          style:UIBarButtonItemStylePlain target:self action:@selector(contact:)];;

在此输入图像描述

In Swift 2, you would do:

let rightButton: UIBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Done, target: nil, action: nil)
self.navigationItem.rightBarButtonItem = rightButton

(Not a major change) In Swift 4/5, it will be:

let rightButton: UIBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItem.Style.done, target: nil, action: nil)
self.navigationItem.rightBarButtonItem = rightButton

Why not use the following: (from Draw custom Back button on iPhone Navigation Bar )

// Add left
UINavigationItem *previousItem = [[UINavigationItem alloc] initWithTitle:@"Back title"];
UINavigationItem *currentItem = [[UINavigationItem alloc] initWithTitle:@"Main Title"];
[self.navigationController.navigationBar setItems:[NSArray arrayWithObjects:previousItem, currentItem, nil] animated:YES];

// set the delegate to self
[self.navigationController.navigationBar setDelegate:self];

swift 3

    let cancelBarButton = UIBarButtonItem(title: "Cancel", style: .done, target: self, action: #selector(cancelPressed(_:)))
    cancelBarButton.setTitleTextAttributes( [NSFontAttributeName : UIFont.cancelBarButtonFont(),
                                                          NSForegroundColorAttributeName : UIColor.white], for: .normal)
    self.navigationItem.leftBarButtonItem = cancelBarButton


    func cancelPressed(_ sender: UIBarButtonItem ) {
        self.dismiss(animated: true, completion: nil)
    }

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM