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
验证的答案没有考虑到文本字段的位置,并有一些错误(双位移,永远不会回到主位置,位移即使文本字段是在视图的顶部…)
这个想法是:
获取焦点TextField的Y的绝对位置 来获取键盘高度 来获取屏幕高度 然后计算键盘位置和文本框之间的距离(如果< 0 ->向上移动视图) 使用UIView。而不是UIView.frame.origin.y -= ..,因为用UIView更容易回到原来的位置。变换= .identity
然后,我们将能够移动视图,只有在必要和特定的位移,以便有聚焦texField刚刚超过键盘
代码如下:
斯威夫特4
class ViewController: UIViewController, UITextFieldDelegate {
var textFieldRealYPosition: CGFloat = 0.0
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(VehiculeViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(VehiculeViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
// Delegate all textfields
}
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
let distanceBetweenTextfielAndKeyboard = self.view.frame.height - textFieldRealYPosition - keyboardSize.height
if distanceBetweenTextfielAndKeyboard < 0 {
UIView.animate(withDuration: 0.4) {
self.view.transform = CGAffineTransform(translationX: 0.0, y: distanceBetweenTextfielAndKeyboard)
}
}
}
}
@objc func keyboardWillHide(notification: NSNotification) {
UIView.animate(withDuration: 0.4) {
self.view.transform = .identity
}
}
func textFieldDidBeginEditing(_ textField: UITextField) {
textFieldRealYPosition = textField.frame.origin.y + textField.frame.height
//take in account all superviews from textfield and potential contentOffset if you are using tableview to calculate the real position
}
}
其他回答
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
}
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
}
}
}
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。
斯威夫特5.0:
经过4-5个小时的战斗,我得到了一个简单的扩展UIViewController与简单的代码,就像魅力
*当TextField在键盘上方时,视图不应该移动
*不需要设置常量值为NSLayoutConstraint
*无需第三方库
*无需动画代码
*适用于tableview
*这适用于自动布局/自动调整大小
extension UIViewController {
func addKeyboardObserver() {
NotificationCenter.default.addObserver(self, selector: #selector(keyboardNotifications(notification:)),
name: UIResponder.keyboardWillChangeFrameNotification,
object: nil)
}
func removeKeyboardObserver(){
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
}
// This method will notify when keyboard appears/ dissapears
@objc func keyboardNotifications(notification: NSNotification) {
var txtFieldY : CGFloat = 0.0 //Using this we will calculate the selected textFields Y Position
let spaceBetweenTxtFieldAndKeyboard : CGFloat = 5.0 //Specify the space between textfield and keyboard
var frame = CGRect(x: 0, y: 0, width: 0, height: 0)
if let activeTextField = UIResponder.currentFirst() as? UITextField ?? UIResponder.currentFirst() as? UITextView {
// Here we will get accurate frame of textField which is selected if there are multiple textfields
frame = self.view.convert(activeTextField.frame, from:activeTextField.superview)
txtFieldY = frame.origin.y + frame.size.height
}
if let userInfo = notification.userInfo {
// here we will get frame of keyBoard (i.e. x, y, width, height)
let keyBoardFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue
let keyBoardFrameY = keyBoardFrame!.origin.y
let keyBoardFrameHeight = keyBoardFrame!.size.height
var viewOriginY: CGFloat = 0.0
//Check keyboards Y position and according to that move view up and down
if keyBoardFrameY >= UIScreen.main.bounds.size.height {
viewOriginY = 0.0
} else {
// if textfields y is greater than keyboards y then only move View to up
if txtFieldY >= keyBoardFrameY {
viewOriginY = (txtFieldY - keyBoardFrameY) + spaceBetweenTxtFieldAndKeyboard
//This condition is just to check viewOriginY should not be greator than keyboard height
// if its more than keyboard height then there will be black space on the top of keyboard.
if viewOriginY > keyBoardFrameHeight { viewOriginY = keyBoardFrameHeight }
}
}
//set the Y position of view
self.view.frame.origin.y = -viewOriginY
}
}
}
添加这个扩展的UIResponder得到哪个TextField被选中
extension UIResponder {
static weak var responder: UIResponder?
static func currentFirst() -> UIResponder? {
responder = nil
UIApplication.shared.sendAction(#selector(trap), to: nil, from: nil, for: nil)
return responder
}
@objc private func trap() {
UIResponder.responder = self
}
}
然后在你的任何ViewController中使用这个
override func viewWillAppear(_ animated: Bool) {
self.addKeyboardObserver()
}
override func viewWillDisappear(_ animated: Bool) {
self.removeKeyboardObserver()
}
在func viewWillAppear中注册这个通知(_ animated: Bool) 在func中注销此通知viewWillDisappear(_ animated:Bool) 下载演示文件
将这个添加到你的视图控制器中。效果非常好。只是调整数值。
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(sender: NSNotification) {
self.view.frame.origin.y -= 150
}
@objc func keyboardWillHide(sender: NSNotification) {
self.view.frame.origin.y += 150
}