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")
}
}
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。
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
}
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。
管理键盘的完整代码。
override func viewWillAppear(_ animated: Bool) {
NotificationCenter.default.addObserver(self, selector: #selector(StoryMediaVC.keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(StoryMediaVC.keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}
override func viewWillDisappear(_ animated: Bool) {
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
}
@objc func keyboardWillShow(notification: NSNotification) {
guard let userInfo = notification.userInfo else {return}
guard let keyboardSize = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else {return}
let keyboardFrame = keyboardSize.cgRectValue
if self.view.bounds.origin.y == 0{
self.view.bounds.origin.y += keyboardFrame.height
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if self.view.bounds.origin.y != 0 {
self.view.bounds.origin.y = 0
}
}
