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
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
}
其他回答
这是一个解决方案，不处理从一个textField到另一个切换:
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name: UIKeyboardWillHideNotification, object: nil)
}
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.CGRectValue() {
self.view.frame.origin.y -= keyboardSize.height
}
}
func keyboardWillHide(notification: NSNotification) {
self.view.frame.origin.y = 0
}
要解决这个问题，将keyboardWillShow/Hide替换为以下两个函数:
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.CGRectValue() {
if view.frame.origin.y == 0 {
self.view.frame.origin.y -= keyboardSize.height
}
}
}
func keyboardWillHide(notification: NSNotification) {
if view.frame.origin.y != 0 {
self.view.frame.origin.y = 0
}
}
斯威夫特3.0:
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)
}
@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
}
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if self.view.frame.origin.y != 0 {
self.view.frame.origin.y = 0
}
}
斯威夫特4.0:
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)
}
@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
}
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if self.view.frame.origin.y != 0 {
self.view.frame.origin.y = 0
}
}
斯威夫特4.2:
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y == 0 {
self.view.frame.origin.y -= keyboardSize.height
}
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if self.view.frame.origin.y != 0 {
self.view.frame.origin.y = 0
}
}
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
这个功能应该在Ios中内置，但是我们需要在外部做。 插入以下代码 *当textField在键盘下时移动视图， *当textField在键盘上方时不移动视图 *在需要时根据键盘的高度移动视图。 这在所有情况下都有效并经过测试。
import UIKit
class NamVcc: UIViewController, UITextFieldDelegate
{
@IBOutlet weak var NamTxtBoxVid: UITextField!
var VydTxtBoxVar: UITextField!
var ChkKeyPadDspVar: Bool = false
var KeyPadHytVal: CGFloat!
override func viewDidLoad()
{
super.viewDidLoad()
NamTxtBoxVid.delegate = self
}
override func viewWillAppear(animated: Bool)
{
NSNotificationCenter.defaultCenter().addObserver(self,
selector: #selector(TdoWenKeyPadVyd(_:)),
name:UIKeyboardWillShowNotification,
object: nil);
NSNotificationCenter.defaultCenter().addObserver(self,
selector: #selector(TdoWenKeyPadHyd(_:)),
name:UIKeyboardWillHideNotification,
object: nil);
}
func textFieldDidBeginEditing(TxtBoxPsgVar: UITextField)
{
self.VydTxtBoxVar = TxtBoxPsgVar
}
func textFieldDidEndEditing(TxtBoxPsgVar: UITextField)
{
self.VydTxtBoxVar = nil
}
func textFieldShouldReturn(TxtBoxPsgVar: UITextField) -> Bool
{
self.VydTxtBoxVar.resignFirstResponder()
return true
}
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?)
{
view.endEditing(true)
super.touchesBegan(touches, withEvent: event)
}
func TdoWenKeyPadVyd(NfnPsgVar: NSNotification)
{
if(!self.ChkKeyPadDspVar)
{
self.KeyPadHytVal = (NfnPsgVar.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue().height
var NonKeyPadAraVar: CGRect = self.view.frame
NonKeyPadAraVar.size.height -= self.KeyPadHytVal
let VydTxtBoxCenVal: CGPoint? = VydTxtBoxVar?.frame.origin
if (!CGRectContainsPoint(NonKeyPadAraVar, VydTxtBoxCenVal!))
{
self.ChkKeyPadDspVar = true
UIView.animateWithDuration(1.0,
animations:
{ self.view.frame.origin.y -= (self.KeyPadHytVal)},
completion: nil)
}
else
{
self.ChkKeyPadDspVar = false
}
}
}
func TdoWenKeyPadHyd(NfnPsgVar: NSNotification)
{
if (self.ChkKeyPadDspVar)
{
self.ChkKeyPadDspVar = false
UIView.animateWithDuration(1.0,
animations:
{ self.view.frame.origin.y += (self.KeyPadHytVal)},
completion: nil)
}
}
override func viewDidDisappear(animated: Bool)
{
super.viewWillDisappear(animated)
NSNotificationCenter.defaultCenter().removeObserver(self)
view.endEditing(true)
ChkKeyPadDspVar = false
}
}
|::|有时候视图会向下，在这种情况下使用高度+/- 150:
NonKeyPadAraVar.size.height -= self.KeyPadHytVal + 150
{ self.view.frame.origin.y -= self.KeyPadHytVal - 150},
completion: nil)
{ self.view.frame.origin.y += self.KeyPadHytVal - 150},
completion: nil)
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。
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