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
我改进了其中一个答案,使它与不同的键盘和不同的文本视图/字段在一个页面上工作:
添加观察员:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChange(notification:)), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}
func keyboardWillHide() {
self.view.frame.origin.y = 0
}
func keyboardWillChange(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if YOURTEXTVIEW.isFirstResponder {
self.view.frame.origin.y = -keyboardSize.height
}
}
}
删除观察员:
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
}
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。
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)
}
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
}
}
对于Swift 3,我做了一个UIViewController子类,因为我需要在所有的视图控制器中恒定的行为。
class SomeClassVC: UIViewController {
//MARK: - Lifecycle
override func viewDidLoad() {
super.viewDidLoad()
addKeyboardObservers()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
removeKeyboardObservers()
}
//MARK: - Overrides
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
view.endEditing(true)
}
//MARK: - Help
func addKeyboardObservers() {
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
func removeKeyboardObservers() {
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: self.view.window)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: self.view.window)
}
func keyboardWillShow(notification: NSNotification) {
let keyboardHeight = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.height
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.window?.frame.origin.y = -1 * keyboardHeight!
self.view.layoutIfNeeded()
})
}
func keyboardWillHide(notification: NSNotification) {
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.window?.frame.origin.y = 0
self.view.layoutIfNeeded()
})
}
func resignTextFieldFirstResponders() {
for textField in self.view.subviews where textField is UITextField {
textField.resignFirstResponder()
}
}
func resignAllFirstResponders() {
view.endEditing(true)
}
}
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
}
}