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。
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
对于黑屏错误(Swift 4和4.2)。
我解决了黑屏的问题。在验证方案中,敲击后键盘高度变化,导致黑屏。
必须使用UIKeyboardFrameEndUserInfoKey而不是UIKeyboardFrameBeginUserInfoKey
var isKeyboardAppear = false
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
@objc func keyboardWillShow(notification: NSNotification) {
if !isKeyboardAppear {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y == 0{
self.view.frame.origin.y -= keyboardSize.height
}
}
isKeyboardAppear = true
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if isKeyboardAppear {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y != 0{
self.view.frame.origin.y += keyboardSize.height
}
}
isKeyboardAppear = false
}
}
其他回答
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。
我注意到其他答案涉及从视图中删除一些顶部。如果你想简单地调整视图的大小而不削减任何内容,只需尝试这个方法:)
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.view.setTranslatesAutoresizingMaskIntoConstraints(true)
self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y, self.view.frame.size.width, self.view.frame.height - keyboardSize.height)
}
}
func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.collectionView.setTranslatesAutoresizingMaskIntoConstraints(false)
self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y, self.view.frame.size.width, self.view.frame.height + keyboardSize.height)
}
}
斯威夫特4:
我有一个问题与最接受的答案,其中隐藏键盘并没有返回视图一直到页面的底部(只是部分)。这对我来说很有效(+为Swift 4更新)。
override func viewDidLoad() {
super.viewDidLoad()
self.hideKeyboardWhenTappedAround()
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
@objc func keyboardWillShow(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
}
}
}
@objc 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 = 0
}
}
}
Swift 3更新…
正如其他人所说,你需要在控制器的viewDidLoad()方法中添加通知观察者,如下所示:
NotificationCenter.default.addObserver(forName: .UIKeyboardWillShow, object: nil, queue: nil)
{ notification in
self.keyboardWillShow(notification)
}
NotificationCenter.default.addObserver(forName: .UIKeyboardWillHide, object: nil, queue: nil)
{ notification in
self.keyboardWillHide(notification)
}
NotificationCenter.default.addObserver(forName: .UIKeyboardDidShow, object: nil, queue: nil)
{ _ in
self.enableUserInteraction()
}
NotificationCenter.default.addObserver(forName: .UIKeyboardDidHide, object: nil, queue: nil)
{ _ in
self.enableUserInteraction()
}
记得在适当的地方删除你的观察器(我在viewWillDisappear()方法中这样做)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillHide, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidHide, object: nil)
然后,实现你的show和hide方法——注意告诉应用程序忽略交互事件的行(beginIgnoringInteractionEvents)。这很重要,因为如果没有它,用户可能会点击一个字段甚至滚动视图,导致第二次发生移位,从而导致可怕的UI故障。在键盘显示和隐藏之前忽略交互事件将防止这种情况:
func keyboardWillShow(notification: Notification)
{
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
{
UIApplication.shared.beginIgnoringInteractionEvents()
self.view.frame.origin.y -= keyboardSize.height
// add this line if you are shifting a scrollView, as in a chat application
self.timelineCollectionView.contentInset.top += keyboardSize.height
}
}
func keyboardWillHide(notification: Notification)
{
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
{
UIApplication.shared.beginIgnoringInteractionEvents()
self.view.frame.origin.y += keyboardSize.height
// add this line if you are shifting a scrollView, as in a chat application
self.timelineCollectionView.contentInset.top -= keyboardSize.height
}
}
最后,重新启用用户交互(记住,这个方法在键盘didShow或didHide之后触发):
func enableUserInteraction()
{
UIApplication.shared.endIgnoringInteractionEvents()
}
对于黑屏错误(Swift 4和4.2)。
我解决了黑屏的问题。在验证方案中,敲击后键盘高度变化,导致黑屏。
必须使用UIKeyboardFrameEndUserInfoKey而不是UIKeyboardFrameBeginUserInfoKey
var isKeyboardAppear = false
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
@objc func keyboardWillShow(notification: NSNotification) {
if !isKeyboardAppear {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y == 0{
self.view.frame.origin.y -= keyboardSize.height
}
}
isKeyboardAppear = true
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if isKeyboardAppear {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y != 0{
self.view.frame.origin.y += keyboardSize.height
}
}
isKeyboardAppear = false
}
}