键盘存在时如何使 UIView 向上移动

Question

我有一个登录页面，对于较小的屏幕（例如 iPhone 4s），键盘可以覆盖登录按钮和密码文本字段等。所以我将用户名文本字段、密码文本字段和登录按钮放入连接到 ViewController 的 UIView作为 loginView，我想检测键盘是否在 loginView 上，它会推送 loginView 而不是覆盖它，当键盘完全打开时推送将停止，所以 loginView 将站在键盘上。并且当键盘关闭时，它会拉 loginView 直到它到达它的第一个位置。

我试过了，但我会推送所有视图

var kbHeight: CGFloat!

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

func animateTextField(up: Bool) {
    var movement = (up ? -kbHeight : kbHeight)

    UIView.animateWithDuration(0.3, animations: {
        self.view.frame = CGRectOffset(self.view.frame, 0, movement)
    })

}

func keyboardWillShow(notification: NSNotification) {

    if let userInfo = notification.userInfo {
        if let keyboardSize =  (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
            kbHeight = keyboardSize.height
            self.animateTextField(true)
        }
    }

}

func keyboardWillHide(notification: NSNotification) {

    self.animateTextField(false)

}

这是我在许多网站上找到的样本，人们和我有同样的问题正在使用它。我用self.loginView.frame = CGRectOffset(self.view.frame, 0, movement) 更改了这个self.view.frame = CGRectOffset(self.view.frame, 0, movement) 行，因为我想推送我的loginView 视图，它里面有文本字段和按钮，但它仍然不起作用并且覆盖登录按钮，所以不能正确推送。如果有人能解释我如何做或向我展示解释它的来源，我会很高兴，我搜索但找不到，也许我错过了。

这是我的用户界面 http://i62.tinypic.com/1bssy.png

感谢您的建议

Answer 1

在您的代码中进行以下更改

替换这个

    func keyboardWillShow(notification: NSNotification) {

        if let userInfo = notification.userInfo {
            if let keyboardSize =  (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
            kbHeight = keyboardSize.height
                self.animateTextField(true)
            }
        }
    }

与

    func keyboardWillShow(notification : NSNotification) {

        var keyboardInfo : NSDictionary = notification.userInfo!

        var kbSize : CGSize = ((keyboardInfo.objectForKey(UIKeyboardFrameEndUserInfoKey)) as! CGRect).size


        var durationValue : NSNumber = keyboardInfo[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
        var animationDuration : NSTimeInterval = durationValue.doubleValue

        let rawAnimationCurveValue = (keyboardInfo[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber).unsignedIntegerValue
        let keyboardAnimationCurve = UIViewAnimationCurve(rawValue: rawAnimationCurveValue)

        let options = UIViewAnimationOptions(UInt((keyboardInfo[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber).integerValue << 16))

        UIView.animateWithDuration(animationDuration, delay: 0, options:options , animations: { () -> Void in

            self.loginView.frame = CGRectMake(self.loginView.frame.origin.x, self.loginView.frame.origin.y - kbSize.height, self.loginView.frame.size.width, self.loginView.frame.size.height)

        }, completion: nil)
    }

和

这个

func keyboardWillHide(notification: NSNotification) {

    self.animateTextField(false)

}

与

    func keyboardWillHide(notification : NSNotification) {

        var keyboardInfo : NSDictionary = notification.userInfo!

        var kbSize : CGSize = ((keyboardInfo.objectForKey(UIKeyboardFrameEndUserInfoKey)) as! CGRect).size


        var durationValue : NSNumber = keyboardInfo[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
        var animationDuration : NSTimeInterval = durationValue.doubleValue

        let rawAnimationCurveValue = (keyboardInfo[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber).unsignedIntegerValue
        let keyboardAnimationCurve = UIViewAnimationCurve(rawValue: rawAnimationCurveValue)

        let options = UIViewAnimationOptions(UInt((keyboardInfo[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber).integerValue << 16))

        UIView.animateWithDuration(animationDuration, delay: 0, options:options , animations: { () -> Void in

            self.loginView.frame = CGRectMake(self.loginView.frame.origin.x, self.loginView.frame.origin.y + kbSize.height, self.loginView.frame.size.width, self.loginView.frame.size.height)

        }, completion: nil)
    }

Answer 2

效果不佳，但您的回答给了我一个意见。这行得通，但是当键盘完全打开时它可以工作，所以它没有动画:)

    func animateTextField(up: Bool) {

    var movement = (up ? -kbHeight : kbHeight)

    UIView.animateWithDuration(0.3, animations: {

        if (up == true) {

            self.loginView.frame = CGRectMake(self.loginView.frame.origin.x, self.loginView.frame.origin.y - self.kbHeight, self.loginView.frame.size.width, self.loginView.frame.size.height)
        } else {

            self.loginView.frame = CGRectMake(self.loginView.frame.origin.x, self.loginView.frame.origin.y + self.kbHeight, self.loginView.frame.size.width, self.loginView.frame.size.height)
        }
    })
}

func keyboardWillHide(notification: NSNotification) {

    self.animateTextField(false)

}

func keyboardDidShow(notification: NSNotification) {

    if let userInfo = notification.userInfo {

        if let keyboardSize =  (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
            kbHeight = keyboardSize.height - self.loginView.frame.size.height
            self.animateTextField(true)
        }
    }
}

当我在 userInfo 行设置断点时，我得到了这个

[UIKeyboardFrameBeginUserInfoKey: NSRect: {{0, 480}, {320, 216}}, UIKeyboardCenterBeginUserInfoKey: NSPoint: {160, 588}, UIKeyboardFrameEndUserInfoKey: NSRect: {{0, 264}, {320, 216}}, UIKeyboardCenterEndUserInfoKey: NSPoint: {160, 372}, UIKeyboardAnimationDurationUserInfoKey: 0.25, UIKeyboardBoundsUserInfoKey: NSRect: {{0, 0}, {320, 216}}, UIKeyboardAnimationCurveUserInfoKey: 7]

如何在keyboardWillShow 函数中启动动画并使用键盘打开动画。我的意思是键盘会开始显示，当它到达视图的边缘时，它会开始推动。我需要在keyboardWillShow 函数中执行此操作，因为keyboardDidShow 有效但不能同时推送视图