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
如果你在同一个VC中有2个或更多的文本字段，用户点击其中一个，然后点击另一个，不调用keyboardWillHide函数，视图会再向上一次，这是不必要的，因为你会有键盘，一个空格，它有键盘的高度，然后视图，使用我编辑的答案中的代码:
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?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.view.frame.origin.y -= keyboardSize.height
}
}
func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.view.frame.origin.y += keyboardSize.height
}
}
为了解决这个问题，将两个函数"KeyboardWillShow/Hide"替换为:
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
if view.frame.origin.y == 0{
self.view.frame.origin.y -= keyboardSize.height
}
}
}
func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
if view.frame.origin.y != 0 {
self.view.frame.origin.y += keyboardSize.height
}
}
}
其他回答
Swift 3更新…
正如其他人所说，你需要在控制器的viewDidLoad()方法中添加通知观察者，如下所示:
NotificationCenter.default.addObserver(forName: .UIKeyboardWillShow, object: nil, queue: nil)
{ notification in
self.keyboardWillShow(notification)
}
NotificationCenter.default.addObserver(forName: .UIKeyboardWillHide, object: nil, queue: nil)
{ notification in
self.keyboardWillHide(notification)
}
NotificationCenter.default.addObserver(forName: .UIKeyboardDidShow, object: nil, queue: nil)
{ _ in
self.enableUserInteraction()
}
NotificationCenter.default.addObserver(forName: .UIKeyboardDidHide, object: nil, queue: nil)
{ _ in
self.enableUserInteraction()
}
记得在适当的地方删除你的观察器(我在viewWillDisappear()方法中这样做)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillHide, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidHide, object: nil)
然后，实现你的show和hide方法——注意告诉应用程序忽略交互事件的行(beginIgnoringInteractionEvents)。这很重要，因为如果没有它，用户可能会点击一个字段甚至滚动视图，导致第二次发生移位，从而导致可怕的UI故障。在键盘显示和隐藏之前忽略交互事件将防止这种情况:
func keyboardWillShow(notification: Notification)
{
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
{
UIApplication.shared.beginIgnoringInteractionEvents()
self.view.frame.origin.y -= keyboardSize.height
// add this line if you are shifting a scrollView, as in a chat application
self.timelineCollectionView.contentInset.top += keyboardSize.height
}
}
func keyboardWillHide(notification: Notification)
{
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
{
UIApplication.shared.beginIgnoringInteractionEvents()
self.view.frame.origin.y += keyboardSize.height
// add this line if you are shifting a scrollView, as in a chat application
self.timelineCollectionView.contentInset.top -= keyboardSize.height
}
}
最后，重新启用用户交互(记住，这个方法在键盘didShow或didHide之后触发):
func enableUserInteraction()
{
UIApplication.shared.endIgnoringInteractionEvents()
}
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
}
}
}
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)
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)
}
}
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)
}
推荐文章
- UICollectionView中的单元格间距
- 我如何在我的iOS应用程序中每n分钟得到一个后台位置更新?
- 如何使用iOS创建GUID/UUID
- 禁用所呈现视图控制器的交互式撤销
- 在Swift中转换字符串为日期
- 点击按钮时如何打开手机设置?
- 如何使用UIVisualEffectView来模糊图像?
- 如何修复UITableView分隔符在iOS 7?
- 故事板中的自定义单元格行高设置没有响应
- 在Swift中使用自定义消息抛出错误/异常的最简单方法?
- 编译器错误:带有Objective-C选择器的方法与前面带有相同Objective-C选择器的声明冲突
- 如何在Swift中获得唯一的设备ID ?
- 如何在Swift中获得枚举值的名称?
- 复制文本到剪贴板与iOS
- 在Swift中根据字符串计算UILabel的大小
