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
@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
}
} }
其他回答
在这个线程中,一个流行的答案使用了以下代码:
func keyboardWillShow(sender: NSNotification) {
self.view.frame.origin.y -= 150
}
func keyboardWillHide(sender: NSNotification) {
self.view.frame.origin.y += 150
}
用一个静态量来抵消你的视图有一个明显的问题。它在一个设备上看起来很好,但在任何其他尺寸配置上看起来都很糟糕。您需要获取键盘高度并将其用作偏移值。
下面是一种适用于所有设备的解决方案,它可以处理用户在输入时隐藏预测文本字段的边缘情况。
解决方案
下面需要注意的是,我们将self.view.window作为对象参数传入。这将为我们提供来自键盘的数据,比如它的高度!
@IBOutlet weak var messageField: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name:UIKeyboardWillShowNotification, object: self.view.window)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name:UIKeyboardWillHideNotification, object: self.view.window)
}
func keyboardWillHide(sender: NSNotification) {
let userInfo: [NSObject : AnyObject] = sender.userInfo!
let keyboardSize: CGSize = userInfo[UIKeyboardFrameBeginUserInfoKey]!.CGRectValue.size
self.view.frame.origin.y += keyboardSize.height
}
我们将使它在所有设备上看起来都很漂亮,并处理用户添加或删除预测文本字段的情况。
func keyboardWillShow(sender: NSNotification) {
let userInfo: [NSObject : AnyObject] = sender.userInfo!
let keyboardSize: CGSize = userInfo[UIKeyboardFrameBeginUserInfoKey]!.CGRectValue.size
let offset: CGSize = userInfo[UIKeyboardFrameEndUserInfoKey]!.CGRectValue.size
if keyboardSize.height == offset.height {
UIView.animateWithDuration(0.1, animations: { () -> Void in
self.view.frame.origin.y -= keyboardSize.height
})
} else {
UIView.animateWithDuration(0.1, animations: { () -> Void in
self.view.frame.origin.y += keyboardSize.height - offset.height
})
}
}
删除观察者
不要忘记在离开视图之前删除您的观察器,以防止传输不必要的消息。
override func viewWillDisappear(animated: Bool) {
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: self.view.window)
NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: self.view.window)
}
根据评论中的问题更新:
如果你有两个或更多的文本字段,你可以检查你的view.frame.origin.y是否为零。
func keyboardWillShow(sender: NSNotification) {
let userInfo: [NSObject : AnyObject] = sender.userInfo!
let keyboardSize: CGSize = userInfo[UIKeyboardFrameBeginUserInfoKey]!.CGRectValue.size
let offset: CGSize = userInfo[UIKeyboardFrameEndUserInfoKey]!.CGRectValue.size
if keyboardSize.height == offset.height {
if self.view.frame.origin.y == 0 {
UIView.animateWithDuration(0.1, animations: { () -> Void in
self.view.frame.origin.y -= keyboardSize.height
})
}
} else {
UIView.animateWithDuration(0.1, animations: { () -> Void in
self.view.frame.origin.y += keyboardSize.height - offset.height
})
}
print(self.view.frame.origin.y)
}
我做了一个椰子荚来简化问题:
https://github.com/xtrinch/KeyboardLayoutHelper
如何使用:
做一个自动布局底部约束,在模块KeyboardLayoutHelper中给它一个KeyboardLayoutConstraint类,pod将做必要的工作来增加它,以适应出现和消失的键盘。关于如何使用它(我做了两个:一个scrollView内的textFields,和垂直居中的textFields与两个基本视图-登录和注册)的例子项目。
底部布局约束可以是容器视图,textField本身,任何你能想到的。
@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
}
} }
override func viewWillAppear(animated: Bool)
{
super.viewWillAppear(animated)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
}
// MARK: - keyboard
func keyboardWillShow(notification: NSNotification)
{
if let userInfo = notification.userInfo {
if let keyboardSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
let contentInsets = self.tblView.contentInset as UIEdgeInsets
self.tblView.contentInset = UIEdgeInsets(top: contentInsets.top, left: contentInsets.left, bottom: keyboardSize.height, right:contentInsets.right)
// ...
} else {
// no UIKeyboardFrameBeginUserInfoKey entry in userInfo
}
} else {
// no userInfo dictionary in notification
}
}
func keyboardWillHide(notification: NSNotification)
{
let contentInsets = self.tblView.contentInset as UIEdgeInsets
self.tblView.contentInset = UIEdgeInsets(top: contentInsets.top, left: contentInsets.left, bottom: 0, right:contentInsets.right)
}
当打开键盘时,它100%完美地回答了所有人的更新表视图高度
对于Swift4.2
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}
@objc func keyboardWillShow(notification: NSNotification) {
if ((notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue) != nil {
var userInfo = notification.userInfo!
var keyboardFrame:CGRect = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
keyboardFrame = self.view.convert(keyboardFrame, from: nil)
var contentInset:UIEdgeInsets = self.tbl.contentInset
contentInset.bottom = keyboardFrame.size.height
self.tbl.contentInset = contentInset
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if ((notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue) != nil {
let contentInset:UIEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
self.tbl.contentInset = contentInset
}
}
Swift3.2
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
func keyboardWillShow(notification: NSNotification) {
if ((notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue) != nil {
//self.view.frame.origin.y -= keyboardSize.height
var userInfo = notification.userInfo!
var keyboardFrame:CGRect = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
keyboardFrame = self.view.convert(keyboardFrame, from: nil)
var contentInset:UIEdgeInsets = self.tbl.contentInset
contentInset.bottom = keyboardFrame.size.height
self.tbl.contentInset = contentInset
}
}
func keyboardWillHide(notification: NSNotification) {
if ((notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue) != nil {
let contentInset:UIEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
self.tbl.contentInset = contentInset
}
}