Question

我想在UINavigationBar的右侧设置2个按钮。以下是源代码。没有错误，但也没有按钮。这是UIViewController，而不是UINavigationViewController

let buttonEdit: UIButton = UIButton.buttonWithType(UIButtonType.Custom) as! UIButton
buttonEdit.frame = CGRectMake(0, 0, 40, 40)
buttonEdit.setImage(UIImage(named:"me44.png"), forState: UIControlState.Normal)
buttonEdit.addTarget(self, action: "rightNavItemEditClick:", forControlEvents: UIControlEvents.TouchUpInside)
var rightBarButtonItemEdit: UIBarButtonItem = UIBarButtonItem(customView: buttonEdit)

let buttonDelete: UIButton = UIButton.buttonWithType(UIButtonType.Custom) as! UIButton
buttonDelete.frame = CGRectMake(0, 0, 40, 40)
buttonDelete.setImage(UIImage(named:"me44.png"), forState: UIControlState.Normal)
buttonDelete.addTarget(self, action: "rightNavItemDeleteClick:", forControlEvents: UIControlEvents.TouchUpInside)

var rightBarButtonItemDelete: UIBarButtonItem = UIBarButtonItem(customView: buttonDelete)

// add multiple right bar button items       
self.navigationController?.navigationItem.setRightBarButtonItems([rightBarButtonItemDelete, rightBarButtonItemEdit] as [AnyObject], animated: true)

//I also tried code below no luck either
self.navigationItem.setRightBarButtonItems([rightBarButtonItemDelete, rightBarButtonItemEdit] as [AnyObject], animated: true)

Answer 1

这段代码错了：

self.navigationController?.navigationItem.setRightBarButtonItems(
    [rightBarButtonItemDelete, rightBarButtonItemEdit] as [AnyObject], animated: true)

您没有设置导航控制器的navigationItem;你设置你的 navigationItem。此外，[AnyObject]事情是不必要的。所以：

self.navigationItem.setRightBarButtonItems(
    [rightBarButtonItemDelete, rightBarButtonItemEdit], animated: true)

但请注意，仅当您的视图控制器是UINavigationController的子级时才有效。设置视图控制器的navigationItem仅在该情况下自动填充导航栏。如果您在那种情况下不 - 即，如果您的界面中只有一个“松散”的导航栏 - 您需要手动填充导航栏（通过设置< em>它的 navigationItem）。

（另请注意，如果您没有"me44.png"图片，可能是您的代码正在运行，但您只是看到任何内容。）

Answer 2

尽管之前已经说明了，但您可能没有看到添加到导航栏的按钮。对于Swift 3，请在 AppDelegate类中尝试此操作（注意 topItem ）：

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {

    window = UIWindow()
    window?.backgroundColor = UIColor.white

    let navigationVC = UINavigationController(rootViewController: UIViewController())

    let addButton = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(addTodo))
    navigationVC.navigationBar.topItem?.rightBarButtonItem = addButton

    window?.rootViewController = navigationVC
    window?.makeKeyAndVisible()

    return true
}

setRightBarButtonItems不起作用

2 个答案: