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")
}
}
我修改了一点@Simpa解决方案.........
override func viewDidLoad()
{
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("makeSpaceForKeyboard:"), name:UIKeyboardWillShowNotification, object: nil);
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("makeSpaceForKeyboard:"), name:UIKeyboardWillHideNotification, object: nil);
}
deinit{
NSNotificationCenter.defaultCenter().removeObserver(self)
}
var keyboardIsVisible = false
override 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 && keyboardIsVisible == false{
keyboardIsVisible = true
UIView.animateWithDuration(duration, animations: { () -> Void in
var frame = self.view.frame
frame.size.height = frame.size.height - keyboardHeight
self.view.frame = frame
})
} else if keyboardIsVisible == true && notification.name == UIKeyboardWillShowNotification{
}else {
keyboardIsVisible = false
UIView.animateWithDuration(duration, animations: { () -> Void in
var frame = self.view.frame
frame.size.height = frame.size.height + keyboardHeight
self.view.frame = frame
})
}
}
我创建了一个Swift 3协议来处理键盘的出现/消失
import UIKit
protocol KeyboardHandler: class {
var bottomConstraint: NSLayoutConstraint! { get set }
func keyboardWillShow(_ notification: Notification)
func keyboardWillHide(_ notification: Notification)
func startObservingKeyboardChanges()
func stopObservingKeyboardChanges()
}
extension KeyboardHandler where Self: UIViewController {
func startObservingKeyboardChanges() {
// NotificationCenter observers
NotificationCenter.default.addObserver(forName: NSNotification.Name.UIKeyboardWillShow, object: nil, queue: nil) { [weak self] notification in
self?.keyboardWillShow(notification)
}
// Deal with rotations
NotificationCenter.default.addObserver(forName: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil, queue: nil) { [weak self] notification in
self?.keyboardWillShow(notification)
}
// Deal with keyboard change (emoji, numerical, etc.)
NotificationCenter.default.addObserver(forName: NSNotification.Name.UITextInputCurrentInputModeDidChange, object: nil, queue: nil) { [weak self] notification in
self?.keyboardWillShow(notification)
}
NotificationCenter.default.addObserver(forName: NSNotification.Name.UIKeyboardWillHide, object: nil, queue: nil) { [weak self] notification in
self?.keyboardWillHide(notification)
}
}
func keyboardWillShow(_ notification: Notification) {
let verticalPadding: CGFloat = 20 // Padding between the bottom of the view and the top of the keyboard
guard let value = notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue else { return }
let keyboardHeight = value.cgRectValue.height
// Here you could have more complex rules, like checking if the textField currently selected is actually covered by the keyboard, but that's out of this scope.
self.bottomConstraint.constant = keyboardHeight + verticalPadding
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.layoutIfNeeded()
})
}
func keyboardWillHide(_ notification: Notification) {
self.bottomConstraint.constant = 0
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.layoutIfNeeded()
})
}
func stopObservingKeyboardChanges() {
NotificationCenter.default.removeObserver(self)
}
}
然后,要在UIViewController中实现它,执行以下操作:
let the viewController conform to this protocol :
class FormMailVC: UIViewControlle, KeyboardHandler {
start observing keyboard changes in viewWillAppear:
// MARK: - View controller life cycle
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
startObservingKeyboardChanges()
}
stop observing keyboard changes in viewWillDisappear:
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
stopObservingKeyboardChanges()
}
create an IBOutlet for the bottom constraint from the storyboard:
// NSLayoutConstraints
@IBOutlet weak var bottomConstraint: NSLayoutConstraint!
(I recommend having all of your UI embedded inside a "contentView", and linking to this property the bottom constraint from this contentView to the bottom layout guide)
change the constraint priority of the top constraint to 250 (low)
这是为了让整个内容视图在键盘出现时向上滑动。
优先级必须低于子视图中的任何其他约束优先级,包括内容拥抱优先级/内容抗压缩优先级。
确保你的自动布局有足够的约束来决定contentView应该如何滑动。
你可能需要添加一个“大于等于”的约束:
给你!
我使用的Swift 4解决方案需要键盘大小。将serverStatusStackView替换为任何你关心的视图,例如:self.view:
deinit {
NotificationCenter.default.removeObserver(self)
}
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
serverStatusStackView.frame.origin.y = keyboardSize.height * 2 - serverStatusStackView.frame.height
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
serverStatusStackView.frame.origin.y += keyboardSize.height
}
}
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
Well, I think i might be too late but i found another simple version of Saqib's answer. I'm using Autolayout with constraints. I have a small view inside of another main view with username and password fields. Instead of changing the y coordinate of the view i'm saving the original constraint value in a variable and changing the constraint's constant to some value and again after the keyboard dismisses, i'm setting up the constraint to original one. This way it avoids the problem Saqib's answer has, (The view keeps on moving up and does not stop). Below is my code...
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);
self.originalConstraint = self.centerYConstraint.constant
}
func keyboardWillShow(sender: NSNotification) {
self.centerYConstraint.constant += 30
}
func keyboardWillHide(sender: NSNotification) {
self.centerYConstraint.constant = self.originalConstraint
}
这是一个改进版的@JosephLord和@Hlung的回答。
无论你是否有标签栏,它都适用。
并且它可以完美地恢复由键盘移动到原始位置的视图。
// 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()
// Receive(Get) Notification
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardNotification:", name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardNotification:", name: UIKeyboardWillHideNotification, object: nil)
self.originalConstraint = self.keyboardHeightLayoutConstraint?.constant //for original coordinate.
}
func keyboardNotification(notification: NSNotification) {
let isShowing = notification.name == UIKeyboardWillShowNotification
var tabbarHeight: CGFloat = 0
if self.tabBarController? != nil {
tabbarHeight = self.tabBarController!.tabBar.frame.height
}
if let userInfo = notification.userInfo {
let endFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.CGRectValue()
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.keyboardHeightLayoutConstraint?.constant = isShowing ? (endFrame!.size.height - tabbarHeight) : self.originalConstraint!
UIView.animateWithDuration(duration,
delay: NSTimeInterval(0),
options: animationCurve,
animations: { self.view.layoutIfNeeded() },
completion: nil)
}
}
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)
}
}