当键盘出现时，如何在开始编辑时使UITextField上移？

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

您也可以使用textfield委托方法。检查以下代码。当将文本字段放在滚动视图上时，它对我很有用。

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
     if(textField == answer)
    {   
         CGPoint cPoint = textField.frame.origin;
         [scrollView setContentOffset:CGPointMake(0, cPoint.y - 100) animated:YES];
    }
}

注意：您必须根据视图更改cPoint.y-100值。

2012-12-03 17:35:26

其他回答

这里是我创建的UITextfield（和其他类似的字段）类别，它将使文本字段避开键盘，您应该能够将其按原样放置在视图控制器中，它应该可以工作。它将整个屏幕向上移动，使当前文本字段位于带有动画的键盘上方

#import "UIView+avoidKeyboard.h"
#import "AppDelegate.h"

@implementation UIView (avoidKeyboard)

- (void) becomeFirstResponder {

if(self.isFirstResponder)
    return;

[super becomeFirstResponder];

if ([self isKindOfClass:[UISearchBar class]] ||
    [self isKindOfClass:[UITextField class]] ||
    [self isKindOfClass:[UITextView class]])
{
    AppDelegate *appDelegate    = [UIApplication sharedApplication].delegate;

    CGRect screenBounds         = appDelegate.window.frame;

    CGFloat keyboardHeight;
    CGFloat keyboardY;
    CGFloat viewsLowestY;
    CGPoint origin              = [self.superview convertPoint:self.frame.origin toView:appDelegate.window]; //get this views origin in terms of the main screens bounds

    if(UIInterfaceOrientationIsPortrait([[UIApplication sharedApplication] statusBarOrientation])){ //the window.frame doesnt take its orientation into account so if its sideways we must use the x value of the origin instead of the y
        keyboardHeight          = 216;
        keyboardY               = screenBounds.size.height  - keyboardHeight; //find the keyboards y coord relative to how much the main window has moved up
        viewsLowestY            = origin.y + self.frame.size.height; //find the lowest point of this view
    }
    else {
        keyboardHeight          = 162;
        keyboardY               = screenBounds.size.width  - keyboardHeight;
        viewsLowestY            = origin.x + self.frame.size.height;
    }

    CGFloat difference          = viewsLowestY - keyboardY + 20; //find if this view overlaps with the keyboard with some padding

    if (difference > 0){ //move screen up if there is an overlap

        [UIView animateWithDuration:0.3 delay:0.0 options:UIViewAnimationOptionBeginFromCurrentState animations:^{

            CGRect frame = appDelegate.window.frame;

            if(UIInterfaceOrientationIsPortrait([[UIApplication sharedApplication] statusBarOrientation])){
                frame.origin.y -= difference;
            }
            else {
                frame.origin.x -= difference;
            }
            appDelegate.window.frame = frame;
        }
        completion:nil];
    }
}
}

//look at appDelegate to see when the keyboard is hidden

@end

在appDelegate中添加此函数

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardHides:) name:UIKeyboardWillHideNotification object:nil]; //add in didFinishLaunchingWithOptions

...

- (void)keyboardHides:(NSNotification *)notification
{
    [UIView animateWithDuration:0.3 animations:^{
        [window setFrame: CGRectMake(0, 0, window.frame.size.width, window.frame.size.height)];
    } completion:nil];
}

2014-03-14 09:32:57

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
}
}

2017-02-27 08:24:10

它很简单：-

在TextFieldDidBegginEditing中：-

self.view.frame=CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y-150, self.view.frame.size.width, self.view.frame.size.height);

在TextFieldShouldEndEditing中：-

self.view.frame=CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y+150, self.view.frame.size.width, self.view.frame.size.height);

2016-10-11 10:08:33

如果您希望UIView正确移动，并且活动文本字段应准确定位到用户需要的位置，以便用户可以看到输入的内容。

为此，必须使用Scrollview。这假设是您的UIView层次结构。ContainerView->ScrollView->ContentView->您的视图。

如果您已经按照上面讨论的层次结构进行了UIView设计，那么现在在您的控制器类中，您需要在视图中添加通知观察器，并在视图中删除观察器。

但这种方法需要在UIView需要转换的地方添加每个控制器。我一直在使用“TPKeyboardAvoiding”吊舱。无论您是Scrollview、TableView还是CollectionView，它都能可靠且轻松地处理各种可能情况下的UIView转换。您只需要将类传递到“滚动视图”。

如下图所示

如果您是表视图，则可以将此类更改为“TPKeyboardAvoidingTableView”。您可以找到完整的运行项目project Link

我一直遵循这种稳健的开发方法。希望这有帮助！

2019-12-13 06:52:51

实际上，最好只使用苹果的实现，正如文档中所提供的那样。然而，他们提供的代码是错误的。将keyboardWasShow:注释下方的部分替换为以下内容：

NSDictionary* info = [aNotification userInfo];
CGRect keyPadFrame=[[UIApplication sharedApplication].keyWindow convertRect:[[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue] fromView:self.view];
CGSize kbSize =keyPadFrame.size;
CGRect activeRect=[self.view convertRect:activeField.frame fromView:activeField.superview];
CGRect aRect = self.view.bounds;
aRect.size.height -= (kbSize.height);

CGPoint origin =  activeRect.origin;
origin.y -= backScrollView.contentOffset.y;
if (!CGRectContainsPoint(aRect, origin)) {
    CGPoint scrollPoint = CGPointMake(0.0,CGRectGetMaxY(activeRect)-(aRect.size.height));
    [backScrollView setContentOffset:scrollPoint animated:YES];
}

苹果代码存在以下问题：（1）他们总是计算该点是否在视图的框架内，但它是一个ScrollView，因此它可能已经滚动，您需要考虑该偏移：

origin.y -= scrollView.contentOffset.y

（2）他们按键盘的高度移动contentOffset，但我们希望相反（我们希望按屏幕上可见的高度而不是不可见的高度移动contentOffset）：

activeField.frame.origin.y-(aRect.size.height)

2011-01-29 14:56:02

当键盘出现时，如何在开始编辑时使UITextField上移？

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