滚动视图和键盘问题Swift

Question

我有一个内部带有scrollview的视图控制器，并在情节提要板上以这种方式（使用自动布局）进行了设置：

例

如您所见，我在滚动视图的最后一个视图（称为“ viewsotto”）中添加了所有对象。 我的问题是：这些对象中的一些是文本字段，我希望当我点击它并在键盘上显示它可以在文本字段下方时，才能看到我在其中写的内容。 因此，我这样做：

NotificationCenter.default.addObserver(self, selector: #selector(userProfiloGiusto.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(userProfiloGiusto.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)

func keyboardWillShow(notification: NSNotification) {

        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
            if self.view.frame.origin.y == 0{
                self.view.frame.origin.y -= keyboardSize.height
            }
        }

    }

    func keyboardWillHide(notification: NSNotification) {
        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
            if self.view.frame.origin.y != 0{
                self.view.frame.origin.y += keyboardSize.height
            }
        }
    }

但这不起作用。 我究竟做错了什么？

Answer 1

尝试下面的代码。 首先添加var activeField: UITextField? 检查文本字段的可用性。 然后在视图中确实调用了此函数：

override func viewDidLoad() {
    super.viewDidLoad()self.registerForKeyboardNotifications()

    let tap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(self.dismissKeyboard))
    view.addGestureRecognizer(tap)
    tap.cancelsTouchesInView = false}


func registerForKeyboardNotifications()
{
    //Adding notifies on keyboard appearing
    NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(ProfileReviewViewController.keyboardWasShown(_:)), name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(ProfileReviewViewController.keyboardWillBeHidden(_:)), name: UIKeyboardWillHideNotification, object: nil)
}


func deregisterFromKeyboardNotifications()
{
    //Removing notifies on keyboard appearing
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}
func keyboardWasShown(notification: NSNotification)
{
    //Need to calculate keyboard exact size due to Apple suggestions
    let info : NSDictionary = notification.userInfo!
    let keyboardSize = (info[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue().size
    let contentInsets : UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardSize!.height, 0.0)


    self.scrollView.contentInset = contentInsets
    self.scrollView.scrollIndicatorInsets = contentInsets
    var aRect : CGRect = self.view.frame
    aRect.size.height -= keyboardSize!.height
    if activeField != nil
    {
        if (CGRectContainsPoint(aRect, activeField!.frame.origin))
        {
            scrollView.scrollRectToVisible(activeField!.frame, animated: true)
        }
    }
}

func keyboardWillBeHidden(notification: NSNotification)
{
    self.scrollView.contentInset = UIEdgeInsetsZero
}
//MARK : Textfield delegate methods
func textFieldDidBeginEditing(textField: UITextField) {
    activeField = textField
}

func textFieldShouldReturn(textField: UITextField) -> Bool {

    self.view.endEditing(true)
    activeField = nil
    return false
}
func textFieldShouldEndEditing(textField: UITextField) -> Bool {  //delegate method

    activeField = nil
    return true
}
func dismissKeyboard() {
    //Causes the view (or one of its embedded text fields) to resign the first responder status.

    activeField = nil
    view.endEditing(true)
}

Answer 2

您用来理解是否有重叠的读数很可能不正确。
这是一个常见的问题，您需要通过主视图来面对它们，而是应该获取文本字段的框架，进行正确的转换以查看键盘是否与之重叠，并相应地调整scrollview的内容插图。
在管理键盘文档中对此进行了很好的说明。
显示键盘时：

func keyboardWasShown(notification: NSNotification)
{
    let info : NSDictionary = notification.userInfo!
    let keyboardSize = (info[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue().size!
    let contentInsets : UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height, 0.0)


    self.scrollView.contentInset = contentInsets
    self.scrollView.scrollIndicatorInsets = contentInsets

    // If active text field is hidden by keyboard, scroll it so it's visible
    // Your app might not need or want this behavior.
    var aRect : CGRect = self.view.frame
    aRect.size.height -= keyboardSize.height
    if let actField = activeField
    {
        if (CGRectContainsPoint(aRect, actField.frame.origin))
        {
            scrollView.scrollRectToVisible(actField.frame, animated: true)
        }
    }
}

重要的是，当他们询问视图高度时，他们减去键盘高度，然后检查文本视图是否在该区域内。
此计算可能会随您的视图层次结构而变化，因为这是因为框架是视图相对于其超级视图的位置，因此，如果您的rect在另一个视图内，则需要转换其框架以获得与之相关的框架主要观点。