斯威夫特不能动视图。原创。

Question

当键盘出现时，为了不覆盖输入字段，我正在向上移动我的视图。

我这样做的代码如下：

var keyboardShown: Bool = false {
        didSet(oldValue) {
            let keyboardHeight: CGFloat = 216
            var frame = view.frame
            if keyboardShown {
                frame.origin.y = -keyboardHeight
            } else {
                frame.origin.y = 0
            }
            view.frame = frame
        }
    }


    func textFieldDidBeginEditing(textField: UITextField) {
        keyboardShown = true
    }

这是可行的，但没有动画，所以它看起来奇怪的观点，只是跳起来。那么，是否有一个功能，以使这个动画？

另外，我需要打电话给layoutIfNeeded()吗？

提前谢谢你，

Answer 1

我觉得你应该试试这个

在viewDidLoad中为键盘添加这些通知

NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)

当键盘显示或隐藏时，用这些方法做任何事情

func keyboardWillShow(note: NSNotification) {
    var userInfo: [NSObject : AnyObject] = note.userInfo
    var duration: NSTimeInterval = userInfo[UIKeyboardAnimationDurationUserInfoKey].doubleValue()
    var curve: UIViewAnimationCurve = userInfo[UIKeyboardAnimationCurveUserInfoKey].integerValue()
    var keyboardFrameEnd: CGRect = userInfo[UIKeyboardFrameEndUserInfoKey].CGRectValue()
    keyboardFrameEnd = self.view.convertRect(keyboardFrameEnd, fromView: nil)
    UIView.animateWithDuration(duration, delay: 0, options: UIViewAnimationOptionBeginFromCurrentState | curve, animations: {        self.contentView.frame = CGRectMake(0, 0, keyboardFrameEnd.size.width, keyboardFrameEnd.origin.y)

    }, completion: nil)
}

func keyboardWillHide(note: NSNotification) {
    var userInfo: [NSObject : AnyObject] = note.userInfo
    var duration: NSTimeInterval = userInfo[UIKeyboardAnimationDurationUserInfoKey].doubleValue()
    var curve: UIViewAnimationCurve = userInfo[UIKeyboardAnimationCurveUserInfoKey].integerValue()
    var keyboardFrameEnd: CGRect = userInfo[UIKeyboardFrameEndUserInfoKey].CGRectValue()
    keyboardFrameEnd = self.view.convertRect(keyboardFrameEnd, fromView: nil)
    UIView.animateWithDuration(duration, delay: 0, options: UIViewAnimationOptionBeginFromCurrentState | curve, animations: {        self.contentView.frame = CGRectMake(0, 0, keyboardFrameEnd.size.width, keyboardFrameEnd.origin.y)

    }, completion: nil)
}

享受:)