如何为UIBarButtonItem设置标题？

Question

我是初学的iPhone开发者。

如何以编程方式设置UIBarButtonItem的标题？

我的代码如下：

self.navigationItem.rightBarButtonItems =
    UIBarButtonItem(
        barButtonSystemItem: .Cancel, target: self,
        action: "barButtonItemClicked:")

@IBAction func barButtonItemClicked(sender: UIBarButtonItem) {
    //print something
}

Answer 1

使用允许您指定标题的不同初始化程序：

UIBarButtonItem(title: "title", style: .Plain, target: self, action: "barButtonItemClicked:")

Swift 3.1更新

UIBarButtonItem(title: "title", style: .plain, target: self, action: #selector(barButtonItemClicked))

Answer 2

斯威夫特2回答

您可以将以下内容添加到viewDidLoad：

// Some text
self.barButtonItemClicked.title = "Right Button!"

要么

// A Unicode Gear Symbol
// See: http://graphemica.com/%E2%9A%99
self.barButtonItemClicked.title = "\u{2699}"

下面的ViewController.Swift代码将设置您使用的名称barButtonItemClicked。我使用了一个UIBarButtonItem来展示如何设置标题。但要使其适应功能是微不足道的。

import UIKit

class ViewController: UIViewController {

    // Please make sure the line below is properly connected to your Storyboard!
    @IBOutlet weak var barButtonItemClicked: UIBarButtonItem!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

       // Set the text of the NavBarButtonItem Title  
       self.barButtonItemClicked.title = "Right Button!"

       // Gear Icon
       // self.barButtonItemClicked.title = "\u{2699}"

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

Answer 3

就我而言，我想在Edit | Done之间切换。但是，我无法使用leftBarButtonItem，因为我已经有了另一个UIBarButtonItem。

我做的是以下内容：

1-创建@IBOutlet weak var edit: UIBarButtonItem!

2-然后是一个变量来保持状态：var isEditingMode = false

3-现在在viewDidLoad：

override func viewDidLoad() {
    …
    self.edit.action = #selector(self.toogleEditor(_:))
    self.edit.title = "Edit"
    self.setEditing(isEditingMode, animated: true)
    …
}

我将edit.action选择器初始化为我的自定义函数toogleEditor。我希望能够在动作发生时更改标题。

4-创建IBAction：

@IBAction func toogleEditor(sender: AnyObject) {

    if isEditingMode
    {
        isEditingMode = false
        self.edit.title = "Edit"
    }
    else
    {
        isEditingMode = true
        self.edit.title = "Done"
    }
    self.setEditing(isEditingMode, animated: true)
}

每次用户单击UIBarItemButton时都会触发此功能。唯一要做的是使用setEditing(…)来改变UITableViewController的行为。

Answer 4

斯威夫特4：

@IBOutlet var saveButton: UIBarButtonItem!

saveButton.title = "Saved"

Answer 5

来自文档

init(title title: String?,
 style style: UIBarButtonItemStyle,
target target: AnyObject?,
action action: Selector)