我使用Swift与iOS编程,我使用这段代码来移动UITextField,但它不起作用。我正确地调用了函数keyboardWillShow,但是文本字段没有移动。我正在使用自动布局。
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);
}
deinit {
NSNotificationCenter.defaultCenter().removeObserver(self);
}
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
//let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
var frame = self.ChatField.frame
frame.origin.y = frame.origin.y - keyboardSize.height + 167
self.chatField.frame = frame
println("asdasd")
}
}
编辑:我推荐一个更简单、更干净的解决方案。只需将底部间距约束的类更改为KeyboardLayoutConstraint。它会自动展开到键盘高度。
这是一个改进版的@JosephLord的回答。
在iOS 8.3 iPad模拟器上测试,Portrait。Xcode6.3 beta4,我发现他的答案不工作时,键盘隐藏,因为UIKeyboardFrameEndUserInfoKey是“NSRect:{{0, 1024},{768, 264}}”;高度不为0。
这回到使用传统的UIKeyboardWillShowNotification和UIKeyboardWillHideNotification来更好地判断键盘何时隐藏,而不是依赖于结束帧的高度。UIKeyboardWillShowNotification也会在键盘帧改变时发送,所以它应该覆盖所有的用例。
// You have to set this up in storyboard first!.
// It's a vertical spacing constraint between view and bottom of superview.
@IBOutlet weak var bottomSpacingConstraint: NSLayoutConstraint!
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardNotification:"), name:UIKeyboardWillShowNotification, object: nil);
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardNotification:"), name:UIKeyboardWillHideNotification, object: nil);
}
deinit {
NSNotificationCenter.defaultCenter().removeObserver(self)
}
func keyboardNotification(notification: NSNotification) {
let isShowing = notification.name == UIKeyboardWillShowNotification
if let userInfo = notification.userInfo {
let endFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.CGRectValue()
let endFrameHeight = endFrame?.size.height ?? 0.0
let duration:NSTimeInterval = (userInfo[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0
let animationCurveRawNSN = userInfo[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber
let animationCurveRaw = animationCurveRawNSN?.unsignedLongValue ?? UIViewAnimationOptions.CurveEaseInOut.rawValue
let animationCurve:UIViewAnimationOptions = UIViewAnimationOptions(rawValue: animationCurveRaw)
self.bottomSpacingConstraint?.constant = isShowing ? endFrameHeight : 0.0
UIView.animateWithDuration(duration,
delay: NSTimeInterval(0),
options: animationCurve,
animations: { self.view.layoutIfNeeded() },
completion: nil)
}
}
如果你正在使用自动布局,我假设你已经设置了底部空间为Superview约束。如果是这种情况,您只需更新约束的值。这是你如何用一点动画来做到这一点。
func keyboardWasShown(notification: NSNotification) {
let info = notification.userInfo!
let keyboardFrame: CGRect = (info[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue()
UIView.animateWithDuration(0.1, animations: { () -> Void in
self.bottomConstraint.constant = keyboardFrame.size.height + 20
})
}
添加硬编码的20只是为了将文本框弹出到键盘上方一点。否则键盘的上边距和文本框的下边距将会接触。
当键盘关闭时,将约束的值重置为原始值。
另一个解决方案,不依赖于自动布局,约束或任何出口。您所需要的是滚动视图中的字段。
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: "makeSpaceForKeyboard:", name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "makeSpaceForKeyboard:", name: UIKeyboardWillHideNotification, object: nil)
}
func makeSpaceForKeyboard(notification: NSNotification) {
let info = notification.userInfo!
let keyboardHeight:CGFloat = (info[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue().size.height
let duration:Double = info[UIKeyboardAnimationDurationUserInfoKey] as! Double
if notification.name == UIKeyboardWillShowNotification {
UIView.animateWithDuration(duration, animations: { () -> Void in
var frame = self.view.frame
frame.size.height = frame.size.height - keyboardHeight
self.view.frame = frame
})
} else {
UIView.animateWithDuration(duration, animations: { () -> Void in
var frame = self.view.frame
frame.size.height = frame.size.height + keyboardHeight
self.view.frame = frame
})
}
}
我已采取以下方式:
当textfield superview为view时,这很有用
class AdminLoginViewController: UIViewController,
UITextFieldDelegate{
@IBOutlet weak var txtUserName: UITextField!
@IBOutlet weak var txtUserPassword: UITextField!
@IBOutlet weak var btnAdminLogin: UIButton!
private var activeField : UIView?
var param:String!
var adminUser : Admin? = nil
var kbHeight: CGFloat!
override func viewDidLoad()
{
self.addKeyBoardObserver()
self.addGestureForHideKeyBoard()
}
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
func addGestureForHideKeyBoard()
{
let tapGesture = UITapGestureRecognizer(target: self, action: Selector("hideKeyboard"))
tapGesture.cancelsTouchesInView = false
view.addGestureRecognizer(tapGesture)
}
func hideKeyboard() {
self.view.endEditing(true)
}
func addKeyBoardObserver(){
NSNotificationCenter.defaultCenter().addObserver(self, selector: "willChangeKeyboardFrame:",
name:UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "willChangeKeyboardFrame:",
name:UIKeyboardWillHideNotification, object: nil)
}
func removeObserver(){
NSNotificationCenter.defaultCenter().removeObserver(self)
}
//MARK:- textfiled Delegate
func textFieldShouldBeginEditing(textField: UITextField) -> Bool
{
activeField = textField
return true
}
func textFieldShouldEndEditing(textField: UITextField) -> Bool
{
if activeField == textField
{
activeField = nil
}
return true
}
func textFieldShouldReturn(textField: UITextField) -> Bool {
if txtUserName == textField
{
txtUserPassword.becomeFirstResponder()
}
else if (textField == txtUserPassword)
{
self.btnAdminLoginAction(nil)
}
return true;
}
func willChangeKeyboardFrame(aNotification : NSNotification)
{
if self.activeField != nil && self.activeField!.isFirstResponder()
{
if let keyboardSize = (aNotification.userInfo![UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue()
{
let dy = (self.activeField?.superview?.convertRect((self.activeField?.frame)!, toView: view).origin.y)!
let height = (self.view.frame.size.height - keyboardSize.size.height)
if dy > height
{
var frame = self.view.frame
frame.origin.y = -((dy - height) + (self.activeField?.frame.size.height)! + 20)
self.view.frame = frame
}
}
}
else
{
var frame = self.view.frame
frame.origin.y = 0
self.view.frame = frame
}
} }
我正在使用swift 4,我解决了这个问题,没有使用任何额外的底部约束,看我的代码在这里。这对我的案子很有帮助
1)在did load中添加通知观察者
override func viewDidLoad() {
super.viewDidLoad ()
setupManager ()
//加载视图后进行任何额外的设置。
addobserver (self, selector: #selector(self. keyboardwillshow), name: NSNotification.Name。对象:nil)
addobserver (self, selector: #selector(self. keyboardwillhide), name: NSNotification.Name。对象:nil)
}
2)删除通知观察者
Deinit {
NotificationCenter.default.removeObserver(self)
}
3)增加键盘显示/隐藏方法
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.frame.origin.y -= keyboardSize.height
self.view.layoutIfNeeded()
})
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.frame.origin.y += keyboardSize.height
self.view.layoutIfNeeded()
})
}
}
4)添加textfield delegate和touchesBegan方法。usefull用于在屏幕上的textfield外触摸时隐藏键盘
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
view.endEditing(true)
}