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")
}
}
非常简单,不需要编写更多代码。
只需在podfile中添加pod 'IQKeyboardManagerSwift',并在AppDelegate页面中添加下面的代码。
import IQKeyboardManagerSwift
在方法didFinishLaunchingWithOptions()类型中
IQKeyboardManager.shared.enable = true
就是这样。
查看这个视频链接,以更好地了解https://youtu.be/eOM94K1ZWN8
希望这对你有所帮助。
下面是一个简单的解决方案,其中文本字段有一个约束将其绑定到底部布局指南。它只是将键盘高度添加到约束常数中。
// This constraint ties the text field to the bottom layout guide
@IBOutlet var textFieldToBottomLayoutGuideConstraint: NSLayoutConstraint!
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name:UIKeyboardWillShowNotification, object: nil);
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name:UIKeyboardWillHideNotification, object: nil);
}
func keyboardWillShow(sender: NSNotification) {
if let keyboardSize = (sender.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.textFieldToBottomLayoutGuideConstraint?.constant += keyboardSize.height
}
}
func keyboardWillHide(sender: NSNotification) {
if let keyboardSize = (sender.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.textFieldToBottomLayoutGuideConstraint?.constant -= keyboardSize.height
}
}
我喜欢简洁的Swift代码。这是我能想出的最严格的代码,可以用键盘上下移动文本视图。它目前正在iOS8/9 Swift 2生产应用程序中运行。
更新(2016年3月):
我只是尽可能地压缩了之前的代码。此外,这里还有一些流行的答案,它们硬编码了键盘高度和动画参数。这是没有必要的,更不用说这些答案中的数字并不总是与我在6s+ iOS9上看到的实际值一致(键盘高度226,持续时间0.25,动画曲线7)。在任何情况下,几乎不需要额外的代码来直接从系统获取这些值。见下文。
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: "animateWithKeyboard:", name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "animateWithKeyboard:", name: UIKeyboardWillHideNotification, object: nil)
}
func animateWithKeyboard(notification: NSNotification) {
// Based on both Apple's docs and personal experience,
// I assume userInfo and its documented keys are available.
// If you'd like, you can remove the forced unwrapping and add your own default values.
let userInfo = notification.userInfo!
let keyboardHeight = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue().height
let duration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as! Double
let curve = userInfo[UIKeyboardAnimationCurveUserInfoKey] as! UInt
let moveUp = (notification.name == UIKeyboardWillShowNotification)
// baseContraint is your Auto Layout constraint that pins the
// text view to the bottom of the superview.
baseConstraint.constant = moveUp ? -keyboardHeight : 0
let options = UIViewAnimationOptions(rawValue: curve << 16)
UIView.animateWithDuration(duration, delay: 0, options: options,
animations: {
self.view.layoutIfNeeded()
},
completion: nil
)
}
注意:这段代码涵盖了大多数注释/一般情况。然而,处理不同的方向和/或自定义键盘可能需要更多的代码。如果你需要处理每一个场景,这可能会有所帮助。
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
})
}
}