ios - 当键盘可见时，ScrollView 不会自动向上移动

Question

当键盘出现在屏幕上时，我在向上移动 ScrollView 时遇到问题。 我的屏幕上有 4 个文本字段，它们都是数字键盘文本字段，没有下一个/完成返回键，因此我在键盘上添加了带有上一个和下一个按钮的自定义工具栏。 因此，当我使用下一个按钮从一个文本字段移动到另一个文本字段时，光标会正确移动到下一个字段，但 ScrollView 不会向上移动，因此我的文本字段隐藏在键盘后面。我已将 ScrollView 添加到我的 Storyboard中，并设置了文本字段的委托(delegate)。

代码:

override open func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        self.registerForKeyboardNotifications()
        keyboardVisible = false
    }


   override open func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)

        self.deregisterFromKeyboardNotifications()

    }



func registerForKeyboardNotifications ()-> Void   {

        NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWasShown(_:)), name: NSNotification.Name.UIKeyboardDidShow, object: nil)

        NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillBeHidden(_:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)

    }

func deregisterFromKeyboardNotifications () -> Void {
        let center:  NotificationCenter = NotificationCenter.default
        center.removeObserver(self, name: NSNotification.Name.UIKeyboardDidShow, object: nil)
        center.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)


    }





func keyboardWasShown (_ notification: Notification) {
        if(keyboardVisible == true){
            return
        }

        print(scrollView)
        if let keyboardSize = ((notification as NSNotification).userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {

            offset = scrollView!.contentOffset
            print(offset)

            var viewFrame = scrollView!.frame
            viewFrame.size.height -= keyboardSize.height
            scrollView!.frame = viewFrame

            var textFieldRect = activeField?.frame
            textFieldRect?.origin.y += 10;
            scrollView!.scrollRectToVisible(textFieldRect!, animated: true)

            keyboardVisible = true;


        }


    }

  func keyboardWillBeHidden (_ notification: Notification) {

        if(keyboardVisible == false){
            return;
        }
        scrollView.frame = CGRect(x: 0, y: 0, width: scrollViewWidth, height: scrollViewHeight)
        scrollView?.contentOffset  = offset

        keyboardVisible = false


    }


// textfield delegate

//in textfieldDidBeginEditing i m setting custom toolbar on textfield input accesory view
open func textFieldDidBeginEditing(_ textField: UITextField) {
        if(textField == myTextField1){
            myTextField1.inputAccessoryView = myCustomToolbar
            myCustomToolbar?.nextButton.isEnabled = true
            myCustomToolbar?.previousButton.isEnabled = false
            myCustomToolbar?.nextButton.title = "Next"
        }else if(textField == myTextField2){
            myTextField2.inputAccessoryView = myCustomToolbar
            myCustomToolbar?.previousButton.isEnabled = true
            myCustomToolbar?.nextButton.isEnabled = true
            myCustomToolbar?.nextButton.title = "Next"
        }else if(textField == myTextField3){
            myTextField3.inputAccessoryView = myCustomToolbar
            myCustomToolbar?.nextButton.isEnabled = true
            myCustomToolbar?.previousButton.isEnabled = true
            myCustomToolbar?.nextButton.title = "Next"
        }else if(textField == myTextField4){
            myTextField4.inputAccessoryView = myCustomToolbar
            myCustomToolbar?.nextButton.isEnabled = true
            myCustomToolbar?.previousButton.isEnabled = true
            myCustomToolbar?.changeNextToActionButton(withTitle: "Some title")
        }
    }


   open func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
        activeField = textField
        return true
    }


//PnPToolbar Delegate

    public func pnPToolbarNextButtonClicked(_ myCustomToolbar: myCustomToolbar!) {
        if(myTextField1.isFirstResponder){
            myTextField2.becomeFirstResponder()
        }else if(myTextField2.isFirstResponder){
            myTextField3.becomeFirstResponder()
        }else if(myTextField3.isFirstResponder){
            myTextField4.becomeFirstResponder()

        }else if(ifscCode.isFirstResponder){
            //Done call your method
            self.myMethod()
        }
        var textFieldRect = activeField?.frame
        textFieldRect?.origin.y += 10;
        scrollView!.scrollRectToVisible(textFieldRect!, animated: true)
    }

    public func myCustomToolbarPreviousButtonClicked(_ myCustomToolbar: myCustomToolbar!) {
        if(myTextField4.isFirstResponder){
            myTextField3.becomeFirstResponder()
        }else if(myTextField3.isFirstResponder){
            myTextField2.becomeFirstResponder()
        }else if(myTextField2.isFirstResponder){
            myTextField1.becomeFirstResponder()
        }
        var textFieldRect = activeField?.frame
        textFieldRect?.origin.y += 10;
        scrollView!.scrollRectToVisible(textFieldRect!, animated: true)

    }

当我从 myTextField1 移动到 myTextField2 时，光标到达第二个文本字段，但 ScrollView 不会向上移动， ScrollView 的内容大小也不会向上移动到键盘之外。

Answer 1

在 TextField 的委托(delegate)中管理您的标志，如下所示:

 func textFieldDidBeginEditing(_ textField: UITextField) {
        keyboardVisible = true
    }

    func textFieldEndEditings(sender:UITextField) -> Void {
        print(sender.text)
        keyboardVisible = false
    }