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。当用户点击工具栏中的TextField时，我试图将此工具栏用作键盘的inputAccessory。

我发现this question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
    }

}

我得到的是：

*** 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>'

有什么想法吗？

Answer 1

首先要做的事情：

1. 您应该在Storyboard中创建工具栏约束（左，下，右）。
2. 在视图控制器中创建底部约束的插座（从故事板中拖动）。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并创建一个轻触手势以隐藏键盘）
4. 当键盘4.1出现且4.2消失时，您只会更改底部约束值（键盘大小）。您也可以为工具栏设置动画。

类似的东西：

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
    }

}

希望它有所帮助！