我试图通过访问bottomConstraint来移动我的视图，并将其设置为等于键盘的高度。我不确定在用户输入文本时我应该访问哪个约束来移动视图，下面是我显示和隐藏键盘的两个函数：
// MARK: Scroll View Resize on Keyboard Events
func setupViewResizerOnKeyboardShown() {
NotificationCenter.default.addObserver(self,
selector: #selector(keyboardWillShowForResizing),
name: Notification.Name.UIKeyboardWillShow,
object: nil)
NotificationCenter.default.addObserver(self,
selector: #selector(keyboardWillHideForResizing),
name: Notification.Name.UIKeyboardWillHide,
object: nil)
}
// MARK: Keyboard Scroll
func keyboardWillShowForResizing(notification: Notification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
// We're not just minusing the kb height from the view height because
// the view could already have been resized for the keyboard before
// I need to get the bottom constraint and set it equal to keyboardSize.height
} else {
debugPrint("We're showing the keyboard and either the keyboard size or window is nil: panic widely.")
}
}
func keyboardWillHideForResizing(notification: Notification) {
//commentViewBottomConstraint.constant = 0
}
这是我使用所有textField组件设置视图的代码，包括inputsContainerView：
// MARK: Creation for TextFields
let nameTextField: UITextField = {
let tf = UITextField()
tf.placeholder = "Name"
tf.translatesAutoresizingMaskIntoConstraints = false
return tf
}()
let nameSeparatorView: UIView = {
let view = UIView()
view.backgroundColor = UIColor(r: 220, g: 220, b: 220)
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
let emailTextField: UITextField = {
let tf = UITextField()
tf.placeholder = "Email"
tf.translatesAutoresizingMaskIntoConstraints = false
return tf
}()
let emailSeparatorView: UIView = {
let view = UIView()
view.backgroundColor = UIColor(r: 220, g: 220, b: 220)
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
let passwordTextField: UITextField = {
let tf = UITextField()
tf.placeholder = "Password"
tf.translatesAutoresizingMaskIntoConstraints = false
tf.isSecureTextEntry = true
return tf
}()
let profileImageView: UIImageView = {
let imageView = UIImageView()
imageView.image = UIImage(named: "")
imageView.translatesAutoresizingMaskIntoConstraints = false
imageView.contentMode = .scaleAspectFill
return imageView
}()
lazy var loginRegisterSegmentedControl: UISegmentedControl = {
let sc = UISegmentedControl(items: ["Login", "Register"])
sc.translatesAutoresizingMaskIntoConstraints = false
sc.tintColor = UIColor.white
sc.selectedSegmentIndex = 1
sc.addTarget(self, action: #selector(handleLoginRegisterChange), for: .valueChanged)
return sc
}()
//MARK: Change Button (Login/Register)
func handleLoginRegisterChange() {
let title = loginRegisterSegmentedControl.titleForSegment(at: loginRegisterSegmentedControl.selectedSegmentIndex)
loginRegisterButton.setTitle(title, for: UIControlState())
// change height of inputContainerView, but how???
inputsContainerViewHeightAnchor?.constant = loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 100 : 150
// change height of nameTextField
nameTextFieldHeightAnchor?.isActive = false
nameTextFieldHeightAnchor = nameTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 0 : 1/3)
// Hides name placeholder when selected imdex is selected
if loginRegisterSegmentedControl.selectedSegmentIndex == 0 {
nameTextField.placeholder = ""
}
else {
nameTextField.placeholder = "Username"
}
nameTextFieldHeightAnchor?.isActive = true
emailTextFieldHeightAnchor?.isActive = false
emailTextFieldHeightAnchor = emailTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 1/2 : 1/3)
emailTextFieldHeightAnchor?.isActive = true
passwordTextFieldHeightAnchor?.isActive = false
passwordTextFieldHeightAnchor = passwordTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 1/2 : 1/3)
passwordTextFieldHeightAnchor?.isActive = true
}
func setupLoginRegisterSegmentedControl() {
//need x, y, width, height constraints
loginRegisterSegmentedControl.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
loginRegisterSegmentedControl.bottomAnchor.constraint(equalTo: inputsContainerView.topAnchor, constant: -12).isActive = true
loginRegisterSegmentedControl.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor, multiplier: 1).isActive = true
loginRegisterSegmentedControl.heightAnchor.constraint(equalToConstant: 36).isActive = true
}
func setupProfileImageView() {
//need x, y, width, height constraints
profileImageView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
profileImageView.bottomAnchor.constraint(equalTo: loginRegisterSegmentedControl.topAnchor, constant: -12).isActive = true
profileImageView.widthAnchor.constraint(equalToConstant: 150).isActive = true
profileImageView.heightAnchor.constraint(equalToConstant: 150).isActive = true
}
var inputsContainerViewHeightAnchor: NSLayoutConstraint?
var nameTextFieldHeightAnchor: NSLayoutConstraint?
var emailTextFieldHeightAnchor: NSLayoutConstraint?
var passwordTextFieldHeightAnchor: NSLayoutConstraint?
func setupInputsContainerView() {
//need x, y, width, height constraints
inputsContainerView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
inputsContainerView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
inputsContainerView.widthAnchor.constraint(equalTo: view.widthAnchor, constant: -24).isActive = true
inputsContainerViewHeightAnchor = inputsContainerView.heightAnchor.constraint(equalToConstant: 150)
inputsContainerViewHeightAnchor?.isActive = true
inputsContainerView.addSubview(nameTextField)
inputsContainerView.addSubview(nameSeparatorView)
inputsContainerView.addSubview(emailTextField)
inputsContainerView.addSubview(emailSeparatorView)
inputsContainerView.addSubview(passwordTextField)
//need x, y, width, height constraints
nameTextField.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor, constant: 12).isActive = true
nameTextField.topAnchor.constraint(equalTo: inputsContainerView.topAnchor).isActive = true
nameTextField.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
nameTextFieldHeightAnchor = nameTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: 1/3)
nameTextFieldHeightAnchor?.isActive = true
//need x, y, width, height constraints
nameSeparatorView.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor).isActive = true
nameSeparatorView.topAnchor.constraint(equalTo: nameTextField.bottomAnchor).isActive = true
nameSeparatorView.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
nameSeparatorView.heightAnchor.constraint(equalToConstant: 1).isActive = true
//need x, y, width, height constraints
emailTextField.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor, constant: 12).isActive = true
emailTextField.topAnchor.constraint(equalTo: nameTextField.bottomAnchor).isActive = true
emailTextField.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
emailTextFieldHeightAnchor = emailTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: 1/3)
emailTextFieldHeightAnchor?.isActive = true
//need x, y, width, height constraints
emailSeparatorView.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor).isActive = true
emailSeparatorView.topAnchor.constraint(equalTo: emailTextField.bottomAnchor).isActive = true
emailSeparatorView.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
emailSeparatorView.heightAnchor.constraint(equalToConstant: 1).isActive = true
//need x, y, width, height constraints
passwordTextField.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor, constant: 12).isActive = true
passwordTextField.topAnchor.constraint(equalTo: emailTextField.bottomAnchor).isActive = true
passwordTextField.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
passwordTextFieldHeightAnchor = passwordTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: 1/3)
passwordTextFieldHeightAnchor?.isActive = true
}
func setupLoginRegisterButton() {
//need x, y, width, height constraints
loginRegisterButton.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
loginRegisterButton.topAnchor.constraint(equalTo: inputsContainerView.bottomAnchor, constant: 12).isActive = true
loginRegisterButton.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
loginRegisterButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
}
答案 0 :(得分：0)
您的inputsContainerView使用此约束设置它的Y位置
inputsContainerView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
将其置于视图的中心。
没有设置底部约束。
您需要做的第一件事是将此约束保存在属性中（创建var inputsYConstraint属性）
inputsYConstraint = inputsContainerView.centerYAnchor.constraint(equalTo: view.centerYAnchor)
inputsYConstraint.isActive = true
最简单的做法是在约束上设置负常量以将其向上移动。
或者，您可以降低此约束的优先级，并添加一个底部约束，您可以设置键盘出现时更改的最小值。