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
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)
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)
}
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)
我们对KeyboardWillHideNotification的定义做了一些改变。
此解决方案适用于Swift 4.2:
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
@objc func keyboardWillShow(_ notification:Notification) {
if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
self.view.frame.origin.y -= keyboardSize.height
}
}
@objc func keyboardWillHide(_ notification:Notification) {
if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
self.view.frame.origin.y += keyboardSize.height
}
}
所以其他答案似乎都不正确。
iOS上的良好行为键盘应该:
键盘改变大小时自动调整大小(YES IT CAN) 动画的速度与键盘相同 使用与键盘相同的曲线进行动画 如果相关，尊重安全区域。 也适用于iPad/Undocked模式
我的代码使用一个声明为@IBOutlet的NSLayoutConstraint
@IBOutlet private var bottomLayoutConstraint: NSLayoutConstraint!
你也可以使用变换，视图偏移量，....我觉得有了约束就容易多了。它通过在底部设置一个约束来工作，如果你的常量不是0/不是底部，你可能需要修改代码。
代码如下:
// In ViewDidLoad
NotificationCenter.default.addObserver(self, selector: #selector(?MyViewController.keyboardDidChange), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
@objc func keyboardDidChange(notification: Notification) {
let userInfo = notification.userInfo! as [AnyHashable: Any]
let endFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
let animationDuration = userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as! NSNumber
let animationCurve = userInfo[UIResponder.keyboardAnimationCurveUserInfoKey] as! NSNumber
bottomLayoutConstraint.constant = view.frame.height - endFrame.origin.y - view.safeAreaInsets.bottom // If your constraint is not defined as a safeArea constraint you might want to skip the last part.
// Prevents iPad undocked keyboard.
guard endFrame.height != 0, view.frame.height == endFrame.height + endFrame.origin.y else {
bottomLayoutConstraint.constant = 0
return
}
UIView.setAnimationCurve(UIView.AnimationCurve(rawValue: animationCurve.intValue)!)
UIView.animate(withDuration: animationDuration.doubleValue) {
self.view.layoutIfNeeded()
// Do additional tasks such as scrolling in a UICollectionView
}
}
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