底部的灰色框是文本视图。当我点击文本视图时,键盘将从底部弹出。但是,弹出键盘已覆盖文本视图。
当键盘弹出时,我应该添加什么功能才能向上移动整个视图?
要检测键盘何时出现,您可以收听NSNotificationCenter
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: “keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
这将称为keyboardWillShow
和keyboardWillHide
。在这里,你可以用你的UITextfield
做你想做的事
func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
if let keyboardSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
//use keyboardSize.height to determine the height of the keyboard and set the height of your textfield accordingly
}
}
}
func keyboardWillHide(notification: NSNotification) {
//pull everything down again
}
正如米洛所说,要自己做这件事,你可以注册键盘显示/隐藏通知。
然后,您需要编写代码来确定键盘隐藏的屏幕大小,以及屏幕在相关字段中的位置有多高,这样您就可以知道转移视图的程度。
完成后,您所做的取决于您是使用AutoLayout还是自动调整遮罩(a.k.a。“Struts and springs”样式布局。)
我写了一篇关于项目的开发者博客文章,其中包括用于移动键盘的工作代码。看到这个链接:
http://wareto.com/animating-shapes-using-cashapelayer-and-cabasicanimation
在该帖子中,查找底部标题为“滑动视图以为键盘腾出空间”的链接。
Swift 4完整的解决方案。
我在所有需要它的项目中使用它。
在viewWillAppear上注册以监听键盘显示/隐藏,并使用下面的功能向上和向下移动视图。
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
subscribeToKeyboardNotifications()
}
// stop listening for changes when view is dissappearing
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
unsubscribeFromKeyboardNotifications()
}
// listen for keyboard show/show events
func subscribeToKeyboardNotifications() {
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow(_:)), name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillHide(_:)), name: .UIKeyboardWillHide, object: nil)
}
func unsubscribeFromKeyboardNotifications() {
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillHide, object: nil)
}
@objc func keyboardWillHide(_ notification: Notification) {
view.frame.origin.y = 0
}
在我的情况下,我在底部有一个文本字段,它被键盘隐藏,所以如果它正在使用,那么我将视图向上移动
@objc func keyboardWillShow(_ notification: Notification) {
if bottomTextField.isFirstResponder {
view.frame.origin.y = -getKeyboardHeight(notification: notification)
}
}
func getKeyboardHeight(notification: Notification) -> CGFloat {
let userInfo = notification.userInfo
let keyboardSize = userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue
return keyboardSize.cgRectValue.height
}
斯威夫特4
这段代码不是那么完美,但值得一试!
首先在scrollView中嵌入整个视图。
将这个小可爱功能添加到您的班级:
@objc func keyboardNotification(_ notification: Notification) {
if let userInfo = (notification as NSNotification).userInfo {
let endFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue
let duration:TimeInterval = (userInfo[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0
let animationCurveRawNSN = userInfo[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber
let animationCurveRaw = animationCurveRawNSN?.uintValue ?? UIViewAnimationOptions().rawValue
let animationCurve:UIViewAnimationOptions = UIViewAnimationOptions(rawValue: animationCurveRaw)
if (endFrame?.origin.y)! >= UIScreen.main.bounds.size.height {
scrollViewBottomConstraint?.constant = 0
} else {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
let keyboardHeight:Int = Int(keyboardSize.height)
scrollViewBottomConstraint?.constant = CGFloat(keyboardHeight)
scrollView.setContentOffset(CGPoint(x: 0, y: (scrollViewBottomConstraint?.constant)! / 2), animated: true)
}
}
UIView.animate(withDuration: duration, delay: TimeInterval(0), options: animationCurve, animations: {
self.view.layoutIfNeeded()
}, completion: nil)
}
}
.
将此添加到ViewDidLoad:
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardNotification(_:)), name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil)
不要忘记将scrollView的底部约束连接到您的类(名称为“scrollViewBottomConstraint”)。