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

我最近发现自己在开发消息应用程序时也遇到了类似的情况。我创建了一个自定义的UIView,它粘在键盘顶部,并自动完成您所需的大部分操作

消息生成器视图

(来源:thegamengine.org)

这个项目背后的想法是创建类似于iMessage合成视图AKA的功能:

当键盘关闭时,会粘在键盘顶部并移动到屏幕底部处理文本中的更改控制柄旋转

为了调整/重新配置UIScrollView,您需要使用以下可选委托方法:

-(void)messageComposerFrameDidChange:(CGRect)帧,动画持续时间:(float)持续时间;

每当更改帧(调整大小、重新定位、旋转)时都会调用它,并且还会提供动画持续时间。您可以根据需要使用此信息调整UIScrollView的框架和内容插图的大小。

其他回答

扩展UIViewController的简单解决方案

https://github.com/damienromito/VisibleFormViewController

根据文档,从iOS 3.0开始,当有文本字段的在线编辑时,UITableViewController类会自动调整其表视图的大小并重新定位。我认为将文本字段放在UITableViewCell中是不够的,正如一些人所指出的那样。

从文档中:

表视图控制器支持表视图行的内联编辑;例如,如果行在编辑模式下嵌入了文本字段滚动虚拟键盘上方正在编辑的行显示。

-(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];
}

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!

如果你还在为这件事而挣扎,请阅读我的帖子

我今天提出了一个解决方案。我读过很多关于这个问题的帖子和“教程”,没有一篇在任何情况下都有效(大多数都是相互复制粘贴的)。甚至苹果官方提出的“解决方案”也不起作用,更重要的是,它在横向模式下完全不起作用。苹果公司没有给开发者们解决这样一个常见的基本问题的方法,真是可耻。非常不专业。如此惊人的框架(Cocoa)和如此严重的被低估的问题。

现在,我的解决方案是:让UIScrollView成为您的根视图,然后将所有内容放入其中。然后从这个KeyboardAwareController类子类化视图控制器(您可能需要重新定义scrollView和keyboardPadding方法):

////键盘AwareController.h//社会病////管理员于2014年1月13日创建。//版权所有(c)2014 kuchumovn。保留所有权利。//

#import <UIKit/UIKit.h>

@interface KeyboardAwareController : UIViewController <UITextFieldDelegate>

@end

////键盘AwareController.m//社会病////管理员于2014年1月13日创建。//版权所有(c)2014 kuchumovn。保留所有权利。//

#import "KeyboardAwareController.h"

@interface KeyboardAwareController ()

@end

@implementation KeyboardAwareController
{
    CGPoint scrollPositionBeforeKeyboardAdjustments;

    __weak UIScrollView* scrollView;

    UITextField* activeField;
}

- (id) initWithCoder: (NSCoder*) decoder
{
    if (self = [super initWithCoder:decoder])
    {
        scrollPositionBeforeKeyboardAdjustments = CGPointZero;
    }
    return self;
}

- (void) viewDidLoad
{
    [super viewDidLoad];
}

- (UIScrollView*) scrollView
{
    return (UIScrollView*) self.view;
}

- (CGFloat) keyboardPadding
{
    return 5;
}

- (void) registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification object:nil];

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

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

- (void) deregisterFromKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardWillShowNotification
                                                  object:nil];

    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardDidShowNotification
                                                  object:nil];

    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardWillHideNotification
                                                  object:nil];
}

- (void) viewWillAppear: (BOOL) animated
{
    [super viewWillAppear:animated];

    [self registerForKeyboardNotifications];
}

- (void) viewWillDisappear: (BOOL) animated
{
    [self deregisterFromKeyboardNotifications];

    [super viewWillDisappear:animated];
}

- (void) keyboardWillShow: (NSNotification*) notification
{
    //NSLog(@"keyboardWillShow");

    // force the animation from keyboardWillBeHidden: to end
    scrollView.contentOffset = scrollPositionBeforeKeyboardAdjustments;

    scrollPositionBeforeKeyboardAdjustments = CGPointZero;
}

// warning: i have no idea why this thing works and what does every line of this code mean
// (but it works and there is no other solution on the internets whatsoever)
// P.S. Shame on Apple for missing such a basic functionality from SDK (and many other basic features we have to hack and mess around with for days and nights)

- (void) keyboardDidShow: (NSNotification*) notification
{
    //NSLog(@"keyboardDidShow");

    UIWindow* window = [[[UIApplication sharedApplication] windows]objectAtIndex:0];
    UIView* mainSubviewOfWindow = window.rootViewController.view;

    CGRect keyboardFrameIncorrect = [[[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGRect keyboardFrame = [mainSubviewOfWindow convertRect:keyboardFrameIncorrect fromView:window];
    CGSize keyboardSize = keyboardFrame.size;

    CGRect visibleFrame = CGRectMake(0, 0, 0, 0);
    visibleFrame.origin = self.scrollView.contentOffset;
    visibleFrame.size = self.scrollView.bounds.size;

    CGFloat paddedKeyboardHeight = keyboardSize.height + self.keyboardPadding;

    //NSLog(@"visibleFrame %@", NSStringFromCGRect(visibleFrame));

    visibleFrame.size.height -= paddedKeyboardHeight;

    //NSLog(@"visibleFrame after keyboard height %@", NSStringFromCGRect(visibleFrame));

    if (CGRectContainsPoint(visibleFrame, activeField.frame.origin))
        return;

    scrollPositionBeforeKeyboardAdjustments = scrollView.contentOffset;

    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, activeField.frame.origin.y - visibleFrame.size.height + activeField.frame.size.height, 0);

    contentInsets = UIEdgeInsetsMake(0.0, 0.0, paddedKeyboardHeight, 0);

    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;

    CGSize scrollContentSize = self.scrollView.bounds.size;
    scrollContentSize.height += paddedKeyboardHeight;
    self.scrollView.contentSize = scrollContentSize;

    //NSLog(@"scrollView %@", NSStringFromCGRect(scrollView.frame));
    //NSLog(@"activeField %@", NSStringFromCGRect(activeField.frame));

    //[scrollView scrollRectToVisible:activeField.frame animated:YES];

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

    //NSLog(@"scrollPoint %@", NSStringFromCGPoint(scrollPoint));

    [self.scrollView setContentOffset:scrollPoint animated:YES];
}

- (void) keyboardWillBeHidden: (NSNotification*) notification
{
    //NSLog(@"keyboardWillBeHidden");

    UIEdgeInsets contentInsets = UIEdgeInsetsZero;

    // this doesn't work when changing orientation while the keyboard is visible
    // because when keyboardDidShow: will be called right after this method the contentOffset will still be equal to the old value
    //[scrollView setContentOffset:scrollPositionBeforeKeyboardAdjustments animated:YES];

    [UIView animateWithDuration:.25 animations:^
    {
        self.scrollView.contentInset = contentInsets;
        self.scrollView.scrollIndicatorInsets = contentInsets;

        // replacement for setContentOffset:animated:
        self.scrollView.contentOffset = scrollPositionBeforeKeyboardAdjustments;
    }];
}

- (void) textFieldDidBeginEditing: (UITextField*) textField
{
    activeField = textField;
}

- (void) textFieldDidEndEditing: (UITextField*) textField
{
    activeField = nil;
}
@end

如果您有任何问题,我的项目将在github上托管:https://github.com/kuchumovn/sociopathy.ios

为了更好地解释,我还拍了一张截图: