Question

美好的一天。我面临一个奇怪的问题，当我选择了一行时，我想在我的下一个设置正确的导航项目。我试过了，它已经奏效了。但它却打破了，因为实现doneEditing主体的功能只在下一个视图控制器中，任何帮助都会非常感激。这是我的代码：

 override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "editContact" {

            let indexPath = tableView.indexPathForSelectedRow()
            let destinationVC: NewCategoryViewController = segue.destinationViewController as! NewCategoryViewController
            let contact:Contact = fetchedResultController.objectAtIndexPath(indexPath!) as! Contact
            destinationVC.contact = contact
            var rightAddBarButtonItem:UIBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Plain, target: self, action: "doneEditing:")
            destinationVC.navigationItem.rightBarButtonItem = rightAddBarButtonItem
        }
    }

我的下一个视图控制器是：

import UIKit
import CoreData


class NewCategoryViewController: UIViewController {

    // MARK: - Properties
    var contact: Contact? = nil

// initialize the core data context:
let context = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext

// MARK: - Outlets
@IBOutlet weak var imageHolder: UIImageView!
@IBOutlet weak var nameField: UITextField!
@IBOutlet weak var emailField: UITextField!
@IBOutlet weak var phoneField: UITextField!
@IBOutlet weak var categoryField: UITextField!

// MARK: - Actions
@IBAction func savebtn(sender: AnyObject) {

    let entity = NSEntityDescription.entityForName("Contact", inManagedObjectContext: context!)
    let newContact = Contact(entity: entity!, insertIntoManagedObjectContext: context)
        newContact.name = nameField.text
        newContact.email = emailField.text
        newContact.phone = phoneField.text
        //newContact.photo = UIImageJPEGRepresentation(imageHolder.image, 1)

    var error: NSError?

    context?.save(&error)

    if let errorSaving = error {
        var alert = UIAlertController(title: "Alert", message: "Couldn't save contact !!!", preferredStyle: UIAlertControllerStyle.Alert)
        alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.Default, handler: nil))
        self.presentViewController(alert, animated: true, completion: nil)
    } else {
        nameField.text = ""
        emailField.text = ""
        phoneField.text = ""
        var alert = UIAlertController(title: "Notification", message: "Contact added", preferredStyle: UIAlertControllerStyle.Alert)
        alert.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.Default, handler: nil))
        self.presentViewController(alert, animated: true, completion: nil)
    }

}


override func viewDidLoad() {
    super.viewDidLoad()
    self.title = contact?.name

    if contact != nil {
        nameField.text = contact?.name
        emailField.text = contact?.email
        phoneField.text = contact?.phone

    }
}

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

func doneEditing() {

}

}

Answer 1

将目标从self更改为destinationVC。

使用此：

var rightAddBarButtonItem:UIBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Plain, target: destinationVC, action: "doneEditing:")

当选择器在进行调用的同一个类中定义时，应使用

self。在这种情况下，选择器位于一个单独的类中。

或

我建议你在NewCategoryViewController的viewDidLoad方法中添加正确的栏按钮。在这种情况下，代码将是：

self.navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Plain, target: self, action: "doneEditing:")

和将doneEditing:方法实现为

func doneEditing(sender: UIBarButtonItem) { }

将导航栏项目按钮设置为新标题

1 个答案: