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

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:

其他回答

在这里,我找到了处理键盘的最简单的解决方案。

您只需复制粘贴到示例代码下面,然后更改文本字段或任何要向上移动的视图。

步骤-1

只需在控制器中复制粘贴以下两种方法

- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:)
                                                 name:UIKeyboardDidShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
}

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

步骤-2

在视图中注册和注销键盘通知WillAppear和viewWillDisappear方法。

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

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

步骤-3

灵魂部分来了,只要替换你的文本字段,然后改变高度你想向上移动多少。

- (void)keyboardWasShown:(NSNotification *)notification
{
    NSDictionary* info = [notification userInfo];
    CGSize currentKeyboardSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    //you need replace your textfield instance here
    CGPoint textFieldOrigin = self.tokenForPlaceField.frame.origin;
    CGFloat textFieldHeight = self.tokenForPlaceField.frame.size.height;

    CGRect visibleRect = self.view.frame;
    visibleRect.size.height -= currentKeyboardSize.height;

    if (!CGRectContainsPoint(visibleRect, textFieldOrigin))
    {
        //you can add yor desired height how much you want move keypad up, by replacing "textFieldHeight" below

        CGPoint scrollPoint = CGPointMake(0.0, textFieldOrigin.y - visibleRect.size.height  + textFieldHeight); //replace textFieldHeight to currentKeyboardSize.height, if you want to move up with more height
        [self.scrollView setContentOffset:scrollPoint animated:YES];
    }
}

- (void)keyboardWillBeHidden:(NSNotification *)notification
{
    [self.scrollView setContentOffset:CGPointZero animated:YES];
}

参考:好吧,请感谢这位分享了这个漂亮的代码片段、干净的解决方案的人。

希望这对外面的人会很有帮助。

请遵循以下步骤。

1) 在.h文件中声明以下变量。

  {      
         CGFloat animatedDistance;
  }

2) 在.m文件中声明以下常量。

  static const CGFloat KEYBOARD_ANIMATION_DURATION = 0.3;
  static const CGFloat MINIMUM_SCROLL_FRACTION = 0.2;
  static const CGFloat MAXIMUM_SCROLL_FRACTION = 0.8;
  static const CGFloat PORTRAIT_KEYBOARD_HEIGHT = 216;
  static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 162;

3) 使用UITextField代理向上/向下移动键盘。

  -(void) textFieldDidBeginEditing:(UITextField *)textField
  { 
         if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
         {
               CGRect textFieldRect = [self.view.window convertRect:textField.bounds fromView:textField];
               CGRect viewRect = [self.view.window convertRect:self.view.bounds fromView:self.view];

               CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
               CGFloat numerator =
    midline - viewRect.origin.y
    - MINIMUM_SCROLL_FRACTION * viewRect.size.height;
               CGFloat denominator =
    (MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)
    * viewRect.size.height;
               CGFloat heightFraction = numerator / denominator;

               if (heightFraction < 0.0)
               {
                     heightFraction = 0.0;
               }
               else if (heightFraction > 1.0)
               {
                     heightFraction = 1.0;
               }

               UIInterfaceOrientation orientation =
    [[UIApplication sharedApplication] statusBarOrientation];
               if (orientation == UIInterfaceOrientationPortrait)
               {
                     animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT * heightFraction);
               }
               else
               {
                     animatedDistance = floor(LANDSCAPE_KEYBOARD_HEIGHT * heightFraction);
               }

               CGRect viewFrame = self.view.frame;
               viewFrame.origin.y -= animatedDistance;

               [UIView beginAnimations:nil context:NULL];
               [UIView setAnimationBeginsFromCurrentState:YES];
               [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

               [self.view setFrame:viewFrame];

               [UIView commitAnimations];
       }
  }

  -(void) textFieldDidEndEditing:(UITextField *)textField
  {
       if(UI_USER_INTERFACE_IDIOM()==UIUserInterfaceIdiomPhone)
       {
             CGRect viewFrame = self.view.frame;
             viewFrame.origin.y += animatedDistance;

             [UIView beginAnimations:nil context:NULL];
             [UIView setAnimationBeginsFromCurrentState:YES];
             [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

             [self.view setFrame:viewFrame];

             [UIView commitAnimations];
       }
 }

https://github.com/michaeltyson/TPKeyboardAvoiding下载此文件并添加自定义类,因为它将在您的表视图中管理所有内容,您无需执行任何操作。它有很多选项,你也可以为其他人查看,这是你需要避免使用键盘的全部

这是我为特定布局想出的破解方案。此解决方案与Matt Gallagher的解决方案相似,即将一个部分滚动到视图中。我还是iPhone开发的新手,不熟悉布局的工作原理。因此,这个黑客。

我的实现需要支持在字段中单击时滚动,以及用户在键盘上选择下一个时滚动。

我有一个UIView,身高775。控件基本上以3人一组的方式分布在一个大的空间中。我最终得到了以下IB布局。

UIView -> UIScrollView -> [UI Components]

黑客来了

我将UIScrollView的高度设置为比实际布局(1250)大500个单位。然后,我创建了一个数组,其中包含我需要滚动到的绝对位置,以及一个基于IB标记号获取它们的简单函数。

static NSInteger stepRange[] = {
    0, 0, 0, 0, 0, 0, 0, 0, 0, 140, 140, 140, 140, 140, 410
};

NSInteger getScrollPos(NSInteger i) {
    if (i < TXT_FIELD_INDEX_MIN || i > TXT_FIELD_INDEX_MAX) {
        return 0 ;
    return stepRange[i] ;
}

现在,您需要做的就是在textFieldDidBeginEditing和textFieldShouldReturn中使用以下两行代码(如果要创建下一个字段导航,则使用后者)

CGPoint point = CGPointMake(0, getScrollPos(textField.tag)) ;
[self.scrollView setContentOffset:point animated:YES] ;

一个例子。

- (void) textFieldDidBeginEditing:(UITextField *)textField
{
    CGPoint point = CGPointMake(0, getScrollPos(textField.tag)) ;
    [self.scrollView setContentOffset:point animated:YES] ;
}


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

    NSInteger nextTag = textField.tag + 1;
    UIResponder* nextResponder = [textField.superview viewWithTag:nextTag];

    if (nextResponder) {
        [nextResponder becomeFirstResponder];
        CGPoint point = CGPointMake(0, getScrollPos(nextTag)) ;
        [self.scrollView setContentOffset:point animated:YES] ;
    }
    else{
        [textField resignFirstResponder];
    }

    return YES ;
}

此方法不像其他方法那样“向后滚动”。这不是必需的。同样,这是一个相当“高大”的UIView,我没有时间学习内部布局引擎。

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。