有很多答案可以告诉我们这个方法。我采取了相同的方法，但实施效果不佳。

这是基本想法。我修改了keyboardWasShown方法。

{
// Obtain keyboard Info
NSDictionary* info = [notification userInfo];
CGRect keyboardRect = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue];
keyboardRect = [self.view convertRect:keyboardRect fromView:nil];

// Obtain ScrollView Info w.r.t. top View
CGRect scrollViewRect = [self.view convertRect:self.scrollView.frame fromView:nil];

// Depending upon your screen Ui, Scroll View's bottom edge might be at some offset from screen's bottom
// Calculate the exact offset
int scrollViewBottomOffset = self.view.frame.size.height - (scrollViewRect.origin.y + scrollViewRect.size.height);
int heightToBeAdjusted = keyboardRect.size.height - scrollViewBottomOffset;


// We may also need to consider the Insets if already present with ScrollView. Let's keep it simple for now
// But we should store these, so that we can restore the Insets when Keyboard is gone
// origInsets = self.scrollView.contentInset;

// Set the new Insets for ScrollView
UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, heightToBeAdjusted, 0.0);
self.scrollView.contentInset = contentInsets;
self.scrollView.scrollIndicatorInsets = contentInsets;

// Visible frame (not overlapped by Keyboard)
CGRect visibleFrame = self.view.frame;
visibleFrame.size.height -= keyboardRect.size.height;

// Get the Rect for Textfield w.r.t self.view
CGRect activeFieldFrame = self.activeField.frame;
activeFieldFrame = [self.view convertRect:activeFieldFrame fromView:self.scrollView];

// Check if the TextField is Visible or not
if (!CGRectContainsRect(visibleFrame, activeFieldFrame) ) {
    // Scroll to make it visible but for scrolling use the activeField frame w.r.t. to scroll View
    [self.scrollView scrollRectToVisible:self.activeField.frame animated:YES];
}

}

并添加此方法来初始化activeField

- (IBAction)textFieldDidBeginEditing:(UITextField *)sender
{
self.activeField = sender;
}

RPDP的代码成功地将文本字段移出键盘。但是当你在使用和关闭键盘后滚动到顶部时，顶部已经从视图中向上滚动。模拟器和设备都是如此。要读取该视图顶部的内容，必须重新加载该视图。

他下面的代码难道不应该使视图降低吗？

else
{
    // revert back to the normal state.
    rect.origin.y += kOFFSET_FOR_KEYBOARD;
    rect.size.height -= kOFFSET_FOR_KEYBOARD;
}

这是使用Swift的解决方案。

import UIKit

class ExampleViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet var scrollView: UIScrollView!

    @IBOutlet var textField1: UITextField!
    @IBOutlet var textField2: UITextField!
    @IBOutlet var textField3: UITextField!
    @IBOutlet var textField4: UITextField!
    @IBOutlet var textField5: UITextField!

    var activeTextField: UITextField!

    // MARK: - View
    override func viewDidLoad() {
        super.viewDidLoad()
        self.textField1.delegate = self
        self.textField2.delegate = self
        self.textField3.delegate = self
        self.textField4.delegate = self
        self.textField5.delegate = self
    }

    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)
        self.registerForKeyboardNotifications()
    }

    override func viewWillDisappear(animated: Bool) {
        super.viewWillDisappear(animated)
        self.unregisterFromKeyboardNotifications()
    }

    // MARK: - Keyboard

    // Call this method somewhere in your view controller setup code.
    func registerForKeyboardNotifications() {
        let center:  NSNotificationCenter = NSNotificationCenter.defaultCenter()
        center.addObserver(self, selector: "keyboardWasShown:", name: UIKeyboardDidShowNotification, object: nil)
        center.addObserver(self, selector: "keyboardWillBeHidden:", name: UIKeyboardWillHideNotification, object: nil)
    }

    func unregisterFromKeyboardNotifications () {
        let center:  NSNotificationCenter = NSNotificationCenter.defaultCenter()
        center.removeObserver(self, name: UIKeyboardDidShowNotification, object: nil)
        center.removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    }

    // Called when the UIKeyboardDidShowNotification is sent.
    func keyboardWasShown (notification: NSNotification) {
        let info : NSDictionary = notification.userInfo!
        let kbSize = (info.objectForKey(UIKeyboardFrameBeginUserInfoKey)?.CGRectValue() as CGRect!).size

        let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
        scrollView.contentInset = contentInsets;
        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 = self.view.frame
        aRect.size.height -= kbSize.height;
        if (!CGRectContainsPoint(aRect, self.activeTextField.frame.origin) ) {
            self.scrollView.scrollRectToVisible(self.activeTextField.frame, animated: true)
        }
    }

    // Called when the UIKeyboardWillHideNotification is sent
    func keyboardWillBeHidden (notification: NSNotification) {
        let contentInsets = UIEdgeInsetsZero;
        scrollView.contentInset = contentInsets;
        scrollView.scrollIndicatorInsets = contentInsets;
    }

    // MARK: -  Text Field

    func textFieldDidBeginEditing(textField: UITextField) {
        self.activeTextField = textField
    }

    func textFieldDidEndEditing(textField: UITextField) {
        self.activeTextField = nil
    }

}

@用户271753

要恢复原始视图，请添加：

-(BOOL)textFieldShouldReturn:(UITextField *)textField{
   [textField resignFirstResponder];
   [self setViewMovedUp:NO];
   return YES;
}

对于Swift Developer，使用Swift 3，这里是回购https://github.com/jamesrochabrun/KeyboardWillShow

import UIKit

class ViewController: UIViewController {

    //1 Create a view that will hold your TEXTFIELD
    let textField: UITextField = {
        let tf = UITextField()
        tf.translatesAutoresizingMaskIntoConstraints = false
        tf.layer.borderColor = UIColor.darkGray.cgColor
        tf.layer.borderWidth = 3.0
        return tf
    }()
    //2 global variable that will hold the bottom constraint on changes
    var textfieldBottomAnchor: NSLayoutConstraint?

    override func viewDidLoad() {
        super.viewDidLoad()
        //3 add the view to your controller
        view.addSubview(textField)
        textField.heightAnchor.constraint(equalToConstant: 80).isActive = true
        textField.widthAnchor.constraint(equalToConstant: view.frame.width).isActive = true
        textField.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
        textfieldBottomAnchor = textField.bottomAnchor.constraint(equalTo: view.bottomAnchor)
        textfieldBottomAnchor?.isActive = true

        setUpKeyBoardObservers()
    }
    //4 Use NSnotificationCenter to monitor the keyboard updates
    func setUpKeyBoardObservers() {
        NotificationCenter.default.addObserver(self, selector: #selector(handleKeyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(handleKeyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }

    //5 toggle the bottom layout global variable based on the keyboard's height
    func handleKeyboardWillShow(notification: NSNotification) {

        let keyboardFrame = notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? CGRect
        if let keyboardFrame = keyboardFrame {
            textfieldBottomAnchor?.constant = -keyboardFrame.height
        }
        let keyboardDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? Double
        if let keyboardDuration = keyboardDuration {
            UIView.animate(withDuration: keyboardDuration, animations: {
                self.view.layoutIfNeeded()
            })
        }
    }

    func handleKeyboardWillHide(notification: NSNotification) {

        textfieldBottomAnchor?.constant = 0
        let keyboardDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? Double
        if let keyboardDuration = keyboardDuration {
            UIView.animate(withDuration: keyboardDuration, animations: {
                self.view.layoutIfNeeded()
            })
        }
    }
    //6 remove the observers
    override func viewDidDisappear(_ animated: Bool) {
        super.viewDidDisappear(animated)

        NotificationCenter.default.removeObserver(self)
    }
}

当UITextField位于UITableViewCell中时，应自动设置滚动。

如果不是，可能是因为表视图的代码/设置不正确。

例如，当我重新加载长表时，底部有一个UITextField，如下所示：，

-(void) viewWillAppear:(BOOL)animated
{
   [self.tableview reloadData];
}

然后，当我在文本字段内单击时，底部的文本字段被键盘遮挡。

为了解决这个问题，我必须这样做-

-(void) viewWillAppear:(BOOL)animated
{
    //add the following line to fix issue
    [super viewWillAppear:animated];
    [self.tableview reloadData];
}