使用TextField使UIToolbar向上移动键盘

Question

我有一个带有TextField和Button作为UIBarButtonItem的UIToolbar.当用户点击工具栏内的TextField时,我正在尝试将此工具栏用作键盘的inputAccessory.

我发现这个问题试图解决同样的问题.不幸的是,解决方案无效.

我正在尝试的是:

class ChatViewController: UIViewController, CLLocationManagerDelegate, UITableViewDelegate, UITableViewDataSource {

    @IBOutlet weak var chatTableView: UITableView!
    @IBOutlet weak var chatToolbar: UIToolbar!

    @IBOutlet weak var textFieldBarButtonItem: UIBarButtonItem!

    override func viewDidAppear(animated: Bool) {
        super.viewDidLoad()
        self.chatTableView.delegate = self
        self.chatTableView.dataSource = self
        self.chatToolbar.removeFromSuperview()

    }

    override var inputAccessoryView: UIView{
        get{
            return self.chatToolbar
        }
    }

    override func canBecomeFirstResponder() -> Bool {
        return true
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell{

        let cell = UITableViewCell()
        return cell
    }

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

        return 0
    }

}

而我得到的回报是:

*** Terminating app due to uncaught exception 'UIViewControllerHierarchyInconsistency', reason: 
'child view controller:<UICompatibilityInputViewController: 0x13ff34e00> should have parent view controller:
<App.ChatViewController: 0x13ff21cc0> but requested parent is:<UIInputWindowController: 0x1400b4600>'

有任何想法吗？

Answer 1

首先要做的事情:

1. 您应该在Storyboard(左,下,右)中为工具栏创建约束.
2. 在视图控制器中创建底部约束的出口(从故事板拖动).保存初始约束值(键盘消失时恢复)
3. 创建一个观察者,以了解键盘何时出现和消失(3.1并创建一个轻击手势以隐藏键盘)
4. 当键盘4.1出现并且4.2消失时,您将只更改底部约束值(键盘大小).您也可以为工具栏设置动画.

就像是:

class ChatViewController: UIViewController, CLLocationManagerDelegate, UITableViewDelegate, UITableViewDataSource {

    @IBOutlet weak var chatTableView: UITableView!
    @IBOutlet weak var chatToolbar: UIToolbar!

    @IBOutlet weak var textFieldBarButtonItem: UIBarButtonItem!

    //2
    @IBOutlet weak var toolbarBottomConstraint: NSLayoutConstraint!
    var toolbarBottomConstraintInitialValue: CGFloat?

    override func viewDidAppear(animated: Bool) {
        super.viewDidAppear(animated)
        self.chatTableView.delegate = self
        self.chatTableView.dataSource = self
        self.chatToolbar.removeFromSuperview()

        //2
        self.toolbarBottomConstraintInitialValue = toolbarBottomConstraint.constant
        //3
        enableKeyboardHideOnTap()

    }

    // 3
    // Add a gesture on the view controller to close keyboard when tapped
    private func enableKeyboardHideOnTap(){

        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name: UIKeyboardWillShowNotification, object: nil) // See 4.1
        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name: UIKeyboardWillHideNotification, object: nil) //See 4.2            

        // 3.1
        let tap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: "hideKeyboard")

        self.view.addGestureRecognizer(tap)
    }

    //3.1
    func hideKeyboard() {
        self.view.endEditing(true)
    }

    //4.1
    func keyboardWillShow(notification: NSNotification) {

        let info = notification.userInfo!

        let keyboardFrame: CGRect = (info[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue()

        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double        

        UIView.animateWithDuration(duration) { () -> Void in

            self.toolbarBottomConstraint.constant = keyboardFrame.size.height + 5

            self.view.layoutIfNeeded()

        }

    }

    //4.2
    func keyboardWillHide(notification: NSNotification) {

        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double

        UIView.animateWithDuration(duration) { () -> Void in

            self.toolbarBottomConstraint.constant = self.toolbarBottomConstraintInitialValue!
            self.view.layoutIfNeeded()

        }

    }

    override var inputAccessoryView: UIView{
        get{
            return self.chatToolbar
        }
    }

    override func canBecomeFirstResponder() -> Bool {
        return true
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell{

        let cell = UITableViewCell()
        return cell
    }

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

        return 0
    }

}

希望能帮助到你!