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我遇到顯示鍵盤時更改約束的問題。 我目前正在建立一個登錄屏幕，我已經設置了約束，以在框架中水平和垂直居中一個具有2個文本框和一個按鈕的堆棧視圖。徽標（imageview）位於堆棧視圖之上，並具有獨立的約束。更改鍵盤動畫反彈的故事板約束
當鍵盤出現時，我想動畫的約束來移動stackview和標誌了一下，所以鍵盤不包括任何東西。
鍵盤在字段上還有一個「下一個」按鈕和一個「開始」按鈕。
問題我現在有的是，每次按下「下一步」或清除文本框，約束再次改變，從而stackview和徽標「反彈」，這有點煩人。另外，我知道很多人可能會使用scrollview進行提示，但這不是真正的選擇。 我也有底部的按鈕來創建一個帳戶，所以我也不能真正改變整個框架高度。
我猜測，因爲它調用「textField.resignFirstResponder（）」，「keyboardWillHide」通知被調用，因此它開始動畫。
我在網上到處搜索並嘗試了很多東西來解決它，但我現在真的沒有想法和動力，所以我希望有人對我在這裏可能做錯的想法有所瞭解。 在此先感謝！
class LoginVC: UIViewController, UITextFieldDelegate {
@IBOutlet weak var emailField: SkyFloatingLabelTextFieldWithIcon!
@IBOutlet weak var passwordField: SkyFloatingLabelTextFieldWithIcon!
@IBOutlet weak var signInBtn: TransitionSubmitButton!
@IBOutlet weak var contentCenterConstraint: NSLayoutConstraint!
@IBOutlet weak var logoTopConstraint: NSLayoutConstraint!
@IBOutlet weak var equalWidthConstraint: NSLayoutConstraint!
override func viewDidLoad() {
super.viewDidLoad()
setupKeyboardButtons()
addObservers()
// using extension to hide keyboard when tapped around
self.hideKeyboardWhenTappedAround()
}
func addObservers(){
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.UIKeyboardWillChangeFrame, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(goToDifferentView), name: NSNotification.Name(rawValue: "LoginPressed"), object: nil)
}
func keyboardWillShow(_ notification: NSNotification){
// calling layoutIfNeeded because otherwise text in textfield bounces when animating for some reason
view.layoutIfNeeded()
self.contentCenterConstraint.constant = -50
self.equalWidthConstraint.constant = -30
self.logoTopConstraint.constant = -10
UIView.animate(withDuration: 0.5) {
self.view.layoutIfNeeded()
}
}
func keyboardWillHide(_ notification: NSNotification){
view.layoutIfNeeded()
self.contentCenterConstraint.constant = 0
self.equalWidthConstraint.constant = 0
self.logoTopConstraint.constant = 10
UIView.animate(withDuration: 0.5) {
self.view.layoutIfNeeded()
}
}
private func setupKeyboardButtons(){
// textfield delegates instellen, dit dient om keyboard actions te kunnen doen
self.emailField.delegate = self
self.emailField.enablesReturnKeyAutomatically = true
self.passwordField.delegate = self
self.passwordField.enablesReturnKeyAutomatically = true
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
switch(textField) {
case self.emailField:
self.passwordField.becomeFirstResponder()
break
case self.passwordField:
signInBtn.sendActions(for: .touchUpInside)
break
default:
textField.resignFirstResponder()
break
}
return true
}
// remove observers
override func viewWillDisappear(_ animated: Bool) {
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
}