我有一个应用,它在视图的下半部分有一个文本框。 这意味着当我在文本框中输入时,键盘会覆盖文本框。

我如何在打字时向上移动视图,这样我就可以看到我键入的内容,然后在键盘消失时将它移回原来的位置?

我到处都看了,但所有的解似乎都在Obj-C中,我还不能完全转换。

任何帮助都将不胜感激。


当前回答

在这个线程中,一个流行的答案使用了以下代码:

func keyboardWillShow(sender: NSNotification) {
    self.view.frame.origin.y -= 150
}
func keyboardWillHide(sender: NSNotification) {
    self.view.frame.origin.y += 150
}

用一个静态量来抵消你的视图有一个明显的问题。它在一个设备上看起来很好,但在任何其他尺寸配置上看起来都很糟糕。您需要获取键盘高度并将其用作偏移值。

下面是一种适用于所有设备的解决方案,它可以处理用户在输入时隐藏预测文本字段的边缘情况。

解决方案

下面需要注意的是,我们将self.view.window作为对象参数传入。这将为我们提供来自键盘的数据,比如它的高度!

@IBOutlet weak var messageField: UITextField!

override func viewDidLoad() {
    super.viewDidLoad()

    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name:UIKeyboardWillShowNotification, object: self.view.window)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name:UIKeyboardWillHideNotification, object: self.view.window)
}

func keyboardWillHide(sender: NSNotification) {
    let userInfo: [NSObject : AnyObject] = sender.userInfo!
    let keyboardSize: CGSize = userInfo[UIKeyboardFrameBeginUserInfoKey]!.CGRectValue.size
    self.view.frame.origin.y += keyboardSize.height
}

我们将使它在所有设备上看起来都很漂亮,并处理用户添加或删除预测文本字段的情况。

func keyboardWillShow(sender: NSNotification) {
    let userInfo: [NSObject : AnyObject] = sender.userInfo!
    let keyboardSize: CGSize = userInfo[UIKeyboardFrameBeginUserInfoKey]!.CGRectValue.size
    let offset: CGSize = userInfo[UIKeyboardFrameEndUserInfoKey]!.CGRectValue.size

    if keyboardSize.height == offset.height {
        UIView.animateWithDuration(0.1, animations: { () -> Void in
            self.view.frame.origin.y -= keyboardSize.height
        })
    } else {
        UIView.animateWithDuration(0.1, animations: { () -> Void in
            self.view.frame.origin.y += keyboardSize.height - offset.height
        })
    }
}

删除观察者

不要忘记在离开视图之前删除您的观察器,以防止传输不必要的消息。

override func viewWillDisappear(animated: Bool) {
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: self.view.window)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: self.view.window)
}

根据评论中的问题更新:

如果你有两个或更多的文本字段,你可以检查你的view.frame.origin.y是否为零。

func keyboardWillShow(sender: NSNotification) {
    let userInfo: [NSObject : AnyObject] = sender.userInfo!

    let keyboardSize: CGSize = userInfo[UIKeyboardFrameBeginUserInfoKey]!.CGRectValue.size
    let offset: CGSize = userInfo[UIKeyboardFrameEndUserInfoKey]!.CGRectValue.size

    if keyboardSize.height == offset.height {
        if self.view.frame.origin.y == 0 {
            UIView.animateWithDuration(0.1, animations: { () -> Void in
                self.view.frame.origin.y -= keyboardSize.height
            })
        }
    } else {
        UIView.animateWithDuration(0.1, animations: { () -> Void in
            self.view.frame.origin.y += keyboardSize.height - offset.height
        })
    }
     print(self.view.frame.origin.y)
}

其他回答

Swift 3

func textFieldDidBeginEditing(_ textField: UITextField) { // became first responder

    //move textfields up
    let myScreenRect: CGRect = UIScreen.main.bounds
    let keyboardHeight : CGFloat = 216

    UIView.beginAnimations( "animateView", context: nil)
    var movementDuration:TimeInterval = 0.35
    var needToMove: CGFloat = 0

    var frame : CGRect = self.view.frame
    if (textField.frame.origin.y + textField.frame.size.height + UIApplication.shared.statusBarFrame.size.height > (myScreenRect.size.height - keyboardHeight - 30)) {
        needToMove = (textField.frame.origin.y + textField.frame.size.height + UIApplication.shared.statusBarFrame.size.height) - (myScreenRect.size.height - keyboardHeight - 30);
    }

    frame.origin.y = -needToMove
    self.view.frame = frame
    UIView.commitAnimations()
}

func textFieldDidEndEditing(_ textField: UITextField) {
    //move textfields back down
    UIView.beginAnimations( "animateView", context: nil)
    var movementDuration:TimeInterval = 0.35
    var frame : CGRect = self.view.frame
    frame.origin.y = 0
    self.view.frame = frame
    UIView.commitAnimations()
}

使用以下代码查看UITextField单击

func textFieldDidBeginEditing(textField: UITextField) {
    ViewUpanimateMoving(true, upValue: 100)
}
func textFieldDidEndEditing(textField: UITextField) {
    ViewUpanimateMoving(false, upValue: 100)
}
func ViewUpanimateMoving (up:Bool, upValue :CGFloat){
    var durationMovement:NSTimeInterval = 0.3
    var movement:CGFloat = ( up ? -upValue : upValue)
    UIView.beginAnimations( "animateView", context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)
    UIView.setAnimationDuration(durationMovement)
    self.view.frame = CGRectOffset(self.view.frame, 0,  movement)
    UIView.commitAnimations()
}

最简单的方法,甚至不需要任何代码:

下载KeyboardLayoutConstraint.swift并将文件添加(拖放)到你的项目中,如果你还没有使用Spring动画框架的话。 在你的故事板中,为视图或文本字段创建一个底部约束,选择约束(双击它),在标识检查器中,将其类从NSLayoutConstraint更改为KeyboardLayoutConstraint。 完成了!

物体会随着键盘同步自动移动。

func keyboardWillHide(notification: NSNotification) {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
        if self.view.frame.origin.y != 0{
           // self.view.frame.origin.y += keyboardSize.height
            self.view.frame.origin.y = 0
        }
    }
}

如果你像我一样尝试了以上所有的解决方案,但你的问题仍然没有解决,我有一个很棒的解决方案,它就像一个魅力。首先我想澄清一下上面提到的一些解决方案。

In my case IQkeyboardmanager was working only when there is no auto layout applied on the elements, if it is applied then IQkeyboard manager will not work the way we think. Same thing with upward movement of self.view. i have wriiten a objective c header with a swift support for pushing UITexfield upward when user clicks on it, solving the problem of keyboard covering the UITextfield : https://github.com/coolvasanth/smart_keyboard. One who has An intermediate or higher level in iOS app development can easily understand the repository and implement it. All the best