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
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)
}
}
其他回答
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()
}
@Boris的解决方案非常好,但观点有时会被破坏。
为了实现完美的对齐,请使用下面的代码
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)}
功能:
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y == 0{
self.view.frame.origin.y -= keyboardSize.height
}
}}
And,
@objc func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y != 0{
self.view.frame.origin.y = 0
}
} }
Swift 3代码
var activeField: UITextField?
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(ProfileViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(ProfileViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
func textFieldDidBeginEditing(_ textField: UITextField){
activeField = textField
}
func textFieldDidEndEditing(_ textField: UITextField){
activeField = nil
}
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
if (self.activeField?.frame.origin.y)! >= keyboardSize.height {
self.view.frame.origin.y = keyboardSize.height - (self.activeField?.frame.origin.y)!
} else {
self.view.frame.origin.y = 0
}
}
}
func keyboardWillHide(notification: NSNotification) {
self.view.frame.origin.y = 0
}
我对初学者的两点建议: 在上面的例子中,有人改变坐标,其他人使用“自动调整蒙版”和其他约束:
正如苹果所说,不要将这三种逻辑混合在一起。 如果你在故事板中有约束,不要尝试改变x/y。这绝对行不通。
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)
}
}