使用iOS SDK:

我有一个带UITextFields的UIView,可以启动键盘。我需要它能够:

启动键盘后,允许滚动UIScrollView的内容以查看其他文本字段自动“跳转”(通过向上滚动)或缩短

我知道我需要一个UIScrollView。我已经尝试将UIView的类更改为UIScrollView,但仍然无法上下滚动文本框。

我需要UIView和UIScrollView吗?一个在另一个里面吗?

要自动滚动到活动文本字段,需要执行哪些操作?

理想情况下,尽可能多的组件设置将在Interface Builder中完成。我只想编写需要的代码。

注意:我使用的UIView(或UIScrollView)是由一个选项卡(UITabBar)启动的,它需要正常工作。


我正在添加滚动条,只为键盘出现时使用。尽管不需要它,但我觉得它提供了一个更好的界面,例如,用户可以滚动和更改文本框。

当键盘上下移动时,我可以改变UIScrollView的框架大小。我只是在使用:

-(void)textFieldDidBeginEditing:(UITextField *)textField {
    //Keyboard becomes visible
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
    scrollView.frame.size.width,
    scrollView.frame.size.height - 215 + 50);   // Resize
}

-(void)textFieldDidEndEditing:(UITextField *)textField {
    // Keyboard will hide
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
                                  scrollView.frame.size.width,
                                  scrollView.frame.size.height + 215 - 50); // Resize
}

然而,这不会自动“向上移动”或将可见区域中的下部文本字段居中,这是我真正想要的。


当前回答

我认为如果您使用Swift,最好的方法是使用面向协议的编程。

首先,您必须创建KeyboardCapable协议,使符合该协议的任何UIViewController都能够注册和注销键盘观察员:

import Foundation
import UIKit

protocol KeyboardCapable: KeyboardAnimatable {
    func keyboardWillShow(notification: NSNotification)
    func keyboardWillHide(notification: NSNotification)
}

extension KeyboardCapable where Self: UIViewController {
    func registerKeyboardNotifications() {
        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name:UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name:UIKeyboardWillHideNotification, object: nil)
    }

    func unregisterKeyboardNotifications() {
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    }
}

您已经注意到上述代码中有一个无关的KeyboardAnimatable关键字。这只是我们需要创建的下一个协议的名称:

import Foundation
import UIKit

protocol KeyboardAnimatable {

}

extension KeyboardAnimatable where Self: UIViewController {
    func performKeyboardShowFullViewAnimation(withKeyboardHeight height: CGFloat, andDuration duration: NSTimeInterval) {
        UIView.animateWithDuration(duration, animations: { () -> Void in
            self.view.frame = CGRectMake(view.frame.origin.x, -height, view.bounds.width, view.bounds.height)
            }, completion: nil)
    }

    func performKeyboardHideFullViewAnimation(withDuration duration: NSTimeInterval) {
        UIView.animateWithDuration(duration, animations: { () -> Void in
            self.view.frame = CGRectMake(view.frame.origin.x, 0.0, view.bounds.width, view.bounds.height)
            }, completion: nil)
    }
}

这个KeyboardAnimatable协议为所有符合它的UIViewController提供了两种方法,分别为整个视图上下设置动画。

好的,如果KeyboardCapable符合KeyboardAnimatable,则所有符合Keyboard Capable的UIViewController也符合KeyboaardAnimatable。这很酷。

让我们看看符合KeyboardCapable的UIViewController,并对键盘事件做出反应:

import Foundation
import UIKit

class TransferConfirmViewController: UIViewController, KeyboardCapable {
    //MARK: - LIFE CYCLE       
    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)

        registerKeyboardNotifications()
    }

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

        unregisterKeyboardNotifications()
    }

    //MARK: - NOTIFICATIONS
    //MARK: Keyboard
    func keyboardWillShow(notification: NSNotification) {
        let keyboardHeight = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue().height
        let animationDuration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        performKeyboardShowFullViewAnimation(withKeyboardHeight: keyboardHeight, andDuration: animationDuration)
    }

    func keyboardWillHide(notification: NSNotification) {
        let animationDuration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        performKeyboardHideFullViewAnimation(withDuration: animationDuration)
    }
}

现在,您的UIViewController将响应键盘事件,并将因此产生动画效果。

注意:如果您想要自定义动画而不是推拉视图,则必须在KeyboardAnimatable协议上定义自定义方法或在Keyboard功能上执行这些方法。这取决于你。

其他回答

Swift 3.0版本的苹果键盘管理代码如下:以下代码中使用的FloatingTF是iOS中基于材质设计的文本字段。

import UIKit
class SignupViewController: UIViewController, UITextFieldDelegate {

    //MARK: - IBOutlet:
@IBOutlet weak var emailTF: FloatingTF!
@IBOutlet weak var passwordTF: FloatingTF!
@IBOutlet weak var dobTF: FloatingTF!

@IBOutlet weak var scrollView: UIScrollView!

//MARK: - Variable:
var activeTextField: UITextField!

//MARK: - ViewController Lifecycle:
override func viewDidLoad() {
    super.viewDidLoad()        
    emailTF.delegate = self
    passwordTF.delegate = self
    dobTF.delegate = self 
}
override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

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

   deRegisterKeyboardNotifications()
}

//MARK: - Keyboard notification observer Methods
fileprivate func registerKeyboardNotifications() {
    NotificationCenter.default.addObserver(self, selector: #selector(SignupViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(SignupViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
fileprivate func deRegisterKeyboardNotifications() {
    NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: self.view.window)
    NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidHide, object: self.view.window)
}
func keyboardWillShow(notification: NSNotification) {

    let info: NSDictionary = notification.userInfo! as NSDictionary
    let value: NSValue = info.value(forKey: UIKeyboardFrameBeginUserInfoKey) as! NSValue
    let keyboardSize: CGSize = value.cgRectValue.size
    let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.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: CGRect = self.view.frame
    aRect.size.height -= keyboardSize.height
    let activeTextFieldRect: CGRect? = activeTextField?.frame
    let activeTextFieldOrigin: CGPoint? = activeTextFieldRect?.origin
    if (!aRect.contains(activeTextFieldOrigin!)) {
        scrollView.scrollRectToVisible(activeTextFieldRect!, animated:true)
    }    }

func keyboardWillHide(notification: NSNotification) {
    let contentInsets: UIEdgeInsets = .zero
    scrollView.contentInset = contentInsets
    scrollView.scrollIndicatorInsets = contentInsets
}

//MARK: - UITextField Delegate Methods
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
    if textField == emailTF {
        passwordTF.becomeFirstResponder()
    }
    else if textField == passwordTF {
        dobTF.becomeFirstResponder()
    }
    else {
        self.view.endEditing(true)
    }
    return true
}

func textFieldDidBeginEditing(_ textField: UITextField) {
    activeTextField = textField
    scrollView.isScrollEnabled = true
}

func textFieldDidEndEditing(_ textField: UITextField) {
    activeTextField = nil
    scrollView.isScrollEnabled = false
}
}

我已经组装了一个通用的UIScrollView、UITableView甚至UICollectionView子类,它负责将其中的所有文本字段移到键盘之外。

当键盘即将出现时,子类将找到即将被编辑的子视图,并调整其框架和内容偏移,以确保该视图可见,并使用与键盘弹出窗口匹配的动画。当键盘消失时,它会恢复原来的大小。

它基本上可以与任何设置一起使用,无论是基于UITableView的界面,还是由手动放置的视图组成的界面。

这里是:将文本字段移出键盘的解决方案

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
    }

}
-(BOOL) textFieldShouldBeginEditing:(UITextField *)textField {

  [self slideUp];
   return YES;
}

-(BOOL) textFieldShouldEndEditing:(UITextField *)textField {

    [self slideDown];
   return YES;
}

#pragma mark - Slide Up and Down animation

- (void) slideUp {
    [UIView beginAnimations:nil context:nil];
    layoutView.frame = CGRectMake(0.0, -70.0, layoutView.frame.size.width, layoutView.frame.size.height);

    [UIView commitAnimations];
}


- (void) slideDown {
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDelay: 0.01]; 
    layoutView.frame = CGRectMake(0.0, 0.0, layoutView.frame.size.width, layoutView.frame.size.height);
    [UIView commitAnimations];
}

这是我使用自动布局的版本:

其想法是将包含文本字段/文本视图的视图嵌入UIScrollView中,从底部到其超级视图设置一个约束,创建一个出口,并使用通知根据键盘高度更新其常量。这是基于此处的Apple示例,以及此处使用AutoLayout的UIScrollView上的Apple技术说明。

1) 将视图V嵌入UIScrollView S:如果已经设置了常量和子视图,则可以在ViewController的视图中复制/粘贴视图和子视图;然后使用编辑器->嵌入菜单嵌入视图,最后删除复制的视图。)

2) 设置以下约束:

S到顶部布局指南:0S至底部布局指南:0通向超级视图的S:0S尾随到超级视图:0V顶部空间到超级视图:0V底部空间到超级视图:0超级视图的V尾随空格:0超视图的V前导空格:0V等于S的宽度最新底部V子视图到超级视图:20

3) 从视图控制器的最新约束创建出口

4) 使用以下代码:

@property (weak, nonatomic) IBOutlet NSLayoutConstraint *bottomSpaceToContentView;

// ...

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    // ...

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWasShown:)
                                                 name:UIKeyboardDidShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

#pragma mark - Handle keyboard

// Called when the UIKeyboardDidShowNotification is sent.
- (void)keyboardWasShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    self.bottomSpaceToContentView.constant = kBottomMargin + kbSize.height;
    [self.view layoutIfNeeded];
}

// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    self.bottomSpaceToContentView.constant = kBottomMargin;
    [self.view layoutIfNeeded];
}

哈哈,它起作用了!