Swift 4.2的小变化…

在我的UITableView上，我有很多部分，但我必须避免浮动标题效果，所以我使用了“dummyViewHeight”方法，就像在Stack Overflow上看到的其他地方一样… 这就是我对这个问题的解决方案(它也适用于键盘+工具栏+建议):

将其声明为类常量:

let dummyViewHeight: CGFloat = 40.0

Then

override func viewDidLoad() {
    super.viewDidLoad()
    //... some stuff here, not needed for this example

    // Create non floating header
    tableView.tableHeaderView = UIView(frame: CGRect(x: 0, y: 0, width: tableView.bounds.size.width, height: dummyViewHeight))
    tableView.contentInset = UIEdgeInsets(top: -dummyViewHeight, left: 0, bottom: 0, right: 0)

    addObservers()
}

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

这里所有的魔法……

@objc func keyboardWillShow(notification: NSNotification) {
    if let userInfo = notification.userInfo {
        let keyboardHeight = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as AnyObject).cgRectValue.size.height
        tableView.tableHeaderView = UIView(frame: CGRect(x: 0, y: 0, width: self.tableView.bounds.size.width, height: dummyViewHeight))
        tableView.contentInset = UIEdgeInsets(top: -dummyViewHeight, left: 0, bottom: keyboardHeight, right: 0)
    }
}

@objc func keyboardWillHide(notification: NSNotification) {
    UIView.animate(withDuration: 0.25) {
        self.tableView.tableHeaderView = UIView(frame: CGRect(x: 0, y: 0, width: self.tableView.bounds.size.width, height: self.dummyViewHeight))
        self.tableView.contentInset = UIEdgeInsets(top: -self.dummyViewHeight, left: 0, bottom: 0, right: 0)
    }
}

我经常在我的项目中使用这个。这个解决方案适用于滚动视图，表视图或集合视图，它很容易设置。 它还自动连接键盘上的“下一步”按钮，在文本字段之间切换。

点击这里查看

我尝试了几乎相同的方法，并提出了一个更简单、更小的代码。 我创建了一个IBOutlet iTextView，并与IB中的UITextView相关联。

 -(void)keyboardWillShow:(NSNotification *)notification
    {
        NSLog(@"Keyboard");
        CGRect keyFrame = [[[notification userInfo]objectForKey:UIKeyboardFrameEndUserInfoKey]CGRectValue];

        [UIView beginAnimations:@"resize view" context:nil];
        [UIView setAnimationCurve:1];
        [UIView setAnimationDuration:1.0];
        CGRect frame = iTableView.frame;
        frame.size.height = frame.size.height -  keyFrame.size.height;
        iTableView.frame = frame;
        [iTableView scrollRectToVisible:frame animated:YES];
        [UIView commitAnimations];

    }

Swift 3-4动画和键盘帧改变的解决方案:

首先，创建Bool类型:

// MARK: - Private Properties
private var isKeyboardShowing = false

其次，在系统键盘通知中添加观察者:

// MARK: - Overriding ViewController Life Cycle Methods
override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: .UIKeyboardWillShow, object: nil)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: .UIKeyboardWillHide, object: nil)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChangeFrame), name: .UIKeyboardWillChangeFrame, object: nil)
}

第三，准备动画功能:

func adjustTableViewInsets(keyboardHeight: CGFloat, duration: NSNumber, curve: NSNumber){
    var extraHeight: CGFloat = 0
    if keyboardHeight > 0 {
        extraHeight = 20
        isKeyboardShowing = true
    } else {
        isKeyboardShowing = false
    }

    let contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardHeight + extraHeight, right: 0)
    func animateFunc() {
        //refresh constraints
        //self.view.layoutSubviews()
        tableView.contentInset = contentInset
    }

    UIView.animate(withDuration: TimeInterval(duration), delay: 0, options: [UIViewAnimationOptions(rawValue: UInt(curve))], animations: animateFunc, completion: nil)
}

然后添加target/action方法(由观察者调用):

// MARK: - Target/Selector Actions
func keyboardWillShow(notification: NSNotification) {
    if !isKeyboardShowing {
        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
            let keyboardHeight = keyboardSize.height

            let duration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
            let curve = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber

            adjustTableViewInsets(keyboardHeight: keyboardHeight, duration: duration, curve: curve)
        }
    }
}

func keyboardWillHide(notification: NSNotification) {
    let duration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
    let curve = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber
    adjustTableViewInsets(keyboardHeight: 0, duration: duration, curve: curve)
}

func keyboardWillChangeFrame(notification: NSNotification) {
    if isKeyboardShowing {
        let duration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
        let curve = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as! NSNumber

        if let newKeyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
            let keyboardHeight = newKeyboardSize.height
            adjustTableViewInsets(keyboardHeight: keyboardHeight, duration: duration, curve: curve)
        }
    }
}

最后，不要忘记在deinit或viewWillDisappear中删除观察者:

deinit {
    NotificationCenter.default.removeObserver(self)
}

Swift 4.2完整解决方案

我用一组协议创建了GIST，它简化了显示、隐藏或更改键盘时添加额外空间的工作。

特点:

正确使用键盘帧变化(例如，键盘高度变化，如emojii→普通键盘)。 标签栏和工具栏支持UITableView的例子(在其他例子你收到不正确的插入)。 动态动画持续时间(非硬编码)。 面向协议的方法，可以很容易地为您的目的进行修改。

使用

包含一些滚动视图(当然也支持表格视图)的视图控制器的基本用法示例。

class SomeViewController: UIViewController {
  @IBOutlet weak var scrollView: UIScrollView!

  override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    addKeyboardFrameChangesObserver()
  }

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

extension SomeViewController: ModifableInsetsOnKeyboardFrameChanges {
  var scrollViewToModify: UIScrollView { return scrollView }
}

核心:帧改变观察者

协议KeyboardChangeFrameObserver将在每次键盘帧被改变时触发事件(包括显示，隐藏，帧改变)。

在viewWillAppear()或类似方法调用addKeyboardFrameChangesObserver()。 在viewWillDisappear()或类似的方法调用removeKeyboardFrameChangesObserver()。

实现:滚动视图

ModifableInsetsOnKeyboardFrameChanges协议将UIScrollView支持添加到核心协议。当键盘帧改变时，它改变滚动视图的嵌入。

你的类需要设置滚动视图，一个人的插入将增加/减少键盘帧的变化。

var scrollViewToModify: UIScrollView { get }

我刚刚解决了这样一个问题，我参考了大量的解决方案通过谷歌和堆栈溢出。

首先，请确保你已经为UIScrollView设置了IBOutlet， 那么请仔细看看Apple Doc: Keyboard Management。 最后，如果你可以滚动背景，但键盘仍然覆盖文本字段，请看看这段代码:

// If active text field is hidden by keyboard, scroll it so it's visible
// Your application might not need or want this behavior.
CGRect aRect = self.view.frame;
aRect.size.height -= kbSize.height;

if (aRect.size.height < activeField.frame.origin.y+activeField.frame.size.height) {

    CGPoint scrollPoint = CGPointMake(0.0, activeField.frame.origin.y+activeField.frame.size.height-aRect.size.height);

    [scrollView setContentOffset:scrollPoint animated:YES];

这款游戏与苹果游戏的主要区别在于if条件。我认为apple计算滚动距离和键盘是否覆盖文本字段的条件不准确，所以我做了如上修改。

如果有用请告诉我