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

这可以通过以下代码行使用约束简单地实现

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(keyboardWillShow:)
                                                     name:UIKeyboardWillShowNotification
                                                   object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(keyboardWillHide:)
                                                     name:UIKeyboardWillHideNotification
                                                   object:nil];
}

- (void)keyboardWillShow:(NSNotification *)notification {
    [self adjustTextViewByKeyboardState:YES keyboardInfo:[notification userInfo]];
}

- (void)keyboardWillHide:(NSNotification *)notification {
    [self adjustTextViewByKeyboardState:NO keyboardInfo:[notification userInfo]];
}

- (void)viewDidDisappear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    [super viewDidDisappear:animated];
}

- (void)adjustTextViewByKeyboardState:(BOOL)showKeyboard keyboardInfo:(NSDictionary *)info {
    CGRect keyboardFrame = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGFloat height = keyboardFrame.size.height;
    self.constraintToAdjust.constant = height;        UIViewAnimationCurve animationCurve = [info[UIKeyboardAnimationCurveUserInfoKey] unsignedIntegerValue];
    UIViewAnimationOptions animationOptions = UIViewAnimationOptionBeginFromCurrentState;
    if (animationCurve == UIViewAnimationCurveEaseIn) {
        animationOptions |= UIViewAnimationOptionCurveEaseIn;
    }
    else if (animationCurve == UIViewAnimationCurveEaseInOut) {
        animationOptions |= UIViewAnimationOptionCurveEaseInOut;
    }
    else if (animationCurve == UIViewAnimationCurveEaseOut) {
        animationOptions |= UIViewAnimationOptionCurveEaseOut;
    }
    else if (animationCurve == UIViewAnimationCurveLinear) {
        animationOptions |= UIViewAnimationOptionCurveLinear;
    }
    [UIView animateWithDuration:[[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue] delay:0 options:animationOptions animations:^{
        [self.view layoutIfNeeded];
    }                completion:nil];
}

其他回答

扩展UIViewController的简单解决方案

https://github.com/damienromito/VisibleFormViewController

我发现@DK_是我开始使用的解决方案。然而,假设scrollView覆盖了整个视图。我不是这样的。我只想要一个滚动视图,以防键盘覆盖了登录屏幕上的下文本字段。因此,我的内容视图与滚动视图大小相同,比主视图小。

它也没有考虑到景观,这是我开始遇到麻烦的地方。玩了几天后,这是我的键盘显示:方法。

- (void)keyboardWasShown:(NSNotification*)aNotification
{
    // A lot of the inspiration for this code came from http://stackoverflow.com/a/4837510/594602
    CGFloat height = 0;
    NSDictionary* info = [aNotification userInfo];

    CGRect kbFrameRect = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGRect kbBoundsRect = [self.view convertRect:kbFrameRect fromView:nil]; // Convert frame from window to view coordinates.

    CGRect scrollRect = scrollView.frame;
    CGRect intersect = CGRectIntersection(kbBoundsRect, scrollRect);

    if (!CGRectIsNull(intersect))
    {
        height = intersect.size.height;
        UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, height, 0.0);
        scrollView.contentInset = contentInsets;
        scrollView.scrollIndicatorInsets = contentInsets;
    }

    // Figure out what the view rectangle is for the scrollView
    CGPoint contentOffset = scrollView.contentOffset;
    CGRect visibleRect = CGRectOffset(scrollRect, contentOffset.x, contentOffset.y);    // I'm not 100% sure if this is needed/right. My scrollView was always at the top in testing.
    visibleRect.size.height -= height;
    CGRect activeRect = activeField.frame;

    if (!CGRectContainsRect(visibleRect, activeRect))
    {
        [self.scrollView scrollRectToVisible:activeField.frame animated:YES];
    }
}

我在使用自动布局时也遇到了一些困难。如果我没有正确完成布局,我就没有得到预期的滚动效果。有一件事让生活变得更加简单,那就是将所有要滚动的项目放在一个视图中,并将其作为滚动视图中的唯一项目。我把这个单一视图称为“内容视图”。

我认为关键部分是内容视图有一个设定的宽度和高度。这使得滚动视图能够准确地知道需要处理多少内容。这与通常的布局有点不同。通常情况下,视图会尽量占据更多空间。对于滚动视图的内容,您试图使视图尽可能地限制自己。内容视图允许您停止此操作。所以我给了我248的高度,并使用320的标准屏幕宽度作为我的宽度。

最终对我有用的布局如下:

滚动视图到超级视图:基本上我给了顶部、左侧和右侧的约束。水平空间-视图-滚动视图(0)垂直空间-视图-滚动视图(0)水平空间-滚动视图-视图(0)滚动视图高度:我将滚动视图设置为恒定高度。我不知道这是否真的有必要,但它有滚动视图本身的界限。高度-(248)-滚动视图滚动视图的内容视图:我给了所有方面的常量,顶部、左侧、底部和右侧。垂直空间-视图-滚动视图(0)垂直空间-滚动视图-视图(0)水平空间-视图-滚动视图(0)水平空间-滚动视图-视图(0)内容视图的维度。高度-(248)-视图宽度-(320)-视图

我对UIScrollView由多个UITextField组成也有很多问题,其中一个或多个在编辑时会被键盘遮挡。

如果UIScrollView滚动不正确,请考虑以下几点。

1) 确保contentSize大于UIScrollView框架大小。理解UIScrollViews的方法是UIScrollView就像一个查看contentSize中定义的内容的窗口。因此,如果要让UIScrollview滚动到任何位置,contentSize必须大于UIScrollview。否则,不需要滚动,因为contentSize中定义的所有内容都已可见。BTW,默认contentSize=CGSizeZero。

2) 既然您已经了解到UIScrollView实际上是一个“内容”窗口,那么确保键盘不会遮挡UIScroll View的查看“窗口”的方法就是调整UIScrollView的大小,这样当键盘出现时,UIScrollView窗口的大小就等于UIScrollviewframe.size.height减去键盘的高度。这将确保您的窗口仅是那个小的可视区域。

3) 这里有一个陷阱:当我第一次实现这一点时,我想我必须获得编辑文本字段的CGRect,并调用UIScrollView的scrollRecToVisible方法。我通过调用scrollRecToVisible方法实现了UITextFieldDelegate方法textFieldDidBeginEditing。这实际上产生了一个奇怪的副作用,即滚动会将UITextField捕捉到位。在很长一段时间里,我都搞不清那是什么。然后我注释了textFieldDidBegginEditingDelegate方法,这一切都奏效了!!(???). 事实证明,我相信UIScrollView实际上隐式地将当前编辑的UITextField带入可视窗口。我对UITextFieldDelegate方法的实现以及随后对scrollRecToVisible的调用是多余的,这是产生奇怪副作用的原因。

因此,当键盘出现时,以下是在UIScrollView中正确滚动UITextField的步骤。

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.

- (void)viewDidLoad 
{
    [super viewDidLoad];

    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self 
                                             selector:@selector(keyboardWillShow:) 
                                                 name:UIKeyboardWillShowNotification 
                                               object:self.view.window];
    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self 
                                             selector:@selector(keyboardWillHide:) 
                                                 name:UIKeyboardWillHideNotification 
                                               object:self.view.window];
    keyboardIsShown = NO;
    //make contentSize bigger than your scrollSize (you will need to figure out for your own use case)
    CGSize scrollContentSize = CGSizeMake(320, 345);
    self.scrollView.contentSize = scrollContentSize;
}

- (void)keyboardWillHide:(NSNotification *)n
{
    NSDictionary* userInfo = [n userInfo];

    // get the size of the keyboard
    CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;


    // resize the scrollview
    CGRect viewFrame = self.scrollView.frame;
    // I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
    viewFrame.size.height += (keyboardSize.height - kTabBarHeight);

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [self.scrollView setFrame:viewFrame];
    [UIView commitAnimations];

    keyboardIsShown = NO;
}

- (void)keyboardWillShow:(NSNotification *)n
{
    // This is an ivar I'm using to ensure that we do not do the frame size adjustment on the `UIScrollView` if the keyboard is already shown.  This can happen if the user, after fixing editing a `UITextField`, scrolls the resized `UIScrollView` to another `UITextField` and attempts to edit the next `UITextField`.  If we were to resize the `UIScrollView` again, it would be disastrous.  NOTE: The keyboard notification will fire even when the keyboard is already shown.
    if (keyboardIsShown) {
        return;
    }

    NSDictionary* userInfo = [n userInfo];

    // get the size of the keyboard
    CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;

    // resize the noteView
    CGRect viewFrame = self.scrollView.frame;
    // I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
    viewFrame.size.height -= (keyboardSize.height - kTabBarHeight);

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [self.scrollView setFrame:viewFrame];
    [UIView commitAnimations];
    keyboardIsShown = YES;
}

在viewDidLoad上注册键盘通知在viewDidUnload中注销键盘nofitions确保contentSize设置为大于UIScrollView at viewDidLoad当有键盘时,缩小UIScrollView当键盘离开时,恢复UIScrollView。使用ivar来检测键盘是否已经显示在屏幕上,因为每次UITextField选项卡时都会发送键盘通知,即使键盘已经存在,以避免在UIScrollView已经缩小时缩小它

需要注意的一点是,当您单击另一个UITextField时,即使键盘已经在屏幕上,UIKeyboardWillShowNotification也会启动。当键盘已经在屏幕上时,我使用ivar来避免调整UIScrollView的大小。当键盘已经存在时,不小心调整UIScrollView的大小将是灾难性的!

希望这段代码能让你们中的一些人省去很多麻烦。

斯威夫特4。

您可以使用带有动画的UIKeyBoard轻松上下移动UITextField或UIView

import UIKit

class ViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet var textField: UITextField!
    @IBOutlet var chatView: UIView!

    override func viewDidLoad() {
        super.viewDidLoad()
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChange), name: .UIKeyboardWillChangeFrame, object: nil)
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        textField.resignFirstResponder()
    }

    @objc func keyboardWillChange(notification: NSNotification) {

        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        let curve = notification.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! UInt
        let curFrame = (notification.userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
        let targetFrame = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
        let deltaY = targetFrame.origin.y - curFrame.origin.y
        print("deltaY",deltaY)

        UIView.animateKeyframes(withDuration: duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
            self.chatView.frame.origin.y+=deltaY // Here You Can Change UIView To UITextField
        },completion: nil)
    }

    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
        textField.resignFirstResponder()
        return true
    }

}

这对我有用:

func setupKeyboardNotifications() {
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWasShown:"), name: UIKeyboardDidShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillBeHidden:"), name: UIKeyboardWillHideNotification, object: nil)
}

func keyboardWasShown(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
    let kbSize = infoNSValue.CGRectValue().size
    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDuration(0.3)
    var rect : CGRect = self.view.frame
    rect.size.height -= kbSize.height

    self.view.frame = rect
    UIView.commitAnimations()
}

func keyboardWillBeHidden(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
    let kbSize = infoNSValue.CGRectValue().size
    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDuration(0.3)
    var rect : CGRect = self.view.frame
    rect.size.height += kbSize.height
    self.view.frame = rect
    UIView.commitAnimations()
}