当文本字段被选中时，滚动UITableView

经过大量的试验和错误，我放弃了，并提出了这个问题。我见过很多人有类似的问题，但不能得到所有的答案工作正确。

我有一个由自定义单元格组成的UITableView。单元格由相邻的5个文本字段组成(有点像网格)。

当我试图滚动和编辑UITableView底部的单元格时，我不能设法让我的单元格正确地定位在键盘上方。

我看到过很多关于改变视图大小的回答……但到目前为止，没有一种效果很好。

谁能用一个具体的代码示例来阐明这样做的“正确”方式?

当前回答

结合并填写几个答案(特别是Ortwin Gentz，用户98013)和另一篇文章中的空白，这将适用于iPad上的SDK 4.3的纵向或横向模式:

@implementation UIView (FindFirstResponder)
- (UIResponder *)findFirstResponder
{
  if (self.isFirstResponder) {        
    return self;     
  }

  for (UIView *subView in self.subviews) {
    UIResponder *firstResponder = [subView findFirstResponder];
    if (firstResponder != nil) {
      return firstResponder;
    }
  }

  return nil;
}
@end

@implementation MyViewController

- (UIResponder *)currentFirstResponder {
  return [self.view findFirstResponder];
}

- (IBAction)editingEnded:sender {
  [sender resignFirstResponder];
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {
  [textField resignFirstResponder];
  return NO;
}

- (void)textFieldDidBeginEditing:(UITextField *)textField {
  UITableViewCell *cell = (UITableViewCell*) [[textField superview] superview];
  [_tableView scrollToRowAtIndexPath:[_tableView indexPathForCell:cell] atScrollPosition:UITableViewScrollPositionTop animated:YES];
}

- (void)keyboardWillShow:(NSNotification*)notification {
  if ([self currentFirstResponder] != nil) {
    NSDictionary* userInfo = [notification userInfo];

    // we don't use SDK constants here to be universally compatible with all SDKs ≥ 3.0
    NSValue* keyboardFrameValue = [userInfo objectForKey:@"UIKeyboardBoundsUserInfoKey"];
    if (!keyboardFrameValue) {
      keyboardFrameValue = [userInfo objectForKey:@"UIKeyboardFrameEndUserInfoKey"];
    }

    // Reduce the tableView height by the part of the keyboard that actually covers the tableView
    CGRect windowRect = [[UIApplication sharedApplication] keyWindow].bounds;
    CGRect viewRectAbsolute = [_tableView convertRect:_tableView.bounds toView:[[UIApplication sharedApplication] keyWindow]];
    CGRect frame = _tableView.frame;
    if (UIInterfaceOrientationLandscapeLeft == self.interfaceOrientation ||UIInterfaceOrientationLandscapeRight == self.interfaceOrientation ) {
      windowRect = CGRectMake(windowRect.origin.y, windowRect.origin.x, windowRect.size.height, windowRect.size.width);
      viewRectAbsolute = CGRectMake(viewRectAbsolute.origin.y, viewRectAbsolute.origin.x, viewRectAbsolute.size.height, viewRectAbsolute.size.width);
    }
    frame.size.height -= [keyboardFrameValue CGRectValue].size.height - CGRectGetMaxY(windowRect) + CGRectGetMaxY(viewRectAbsolute);

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[[userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue]];
    _tableView.frame = frame;
    [UIView commitAnimations];

    UITableViewCell *textFieldCell = (id)((UITextField *)self.currentFirstResponder).superview.superview;
    NSIndexPath *textFieldIndexPath = [_tableView indexPathForCell:textFieldCell];

    // iOS 3 sends hide and show notifications right after each other
    // when switching between textFields, so cancel -scrollToOldPosition requests
    [NSObject cancelPreviousPerformRequestsWithTarget:self];
    _topmostRowBeforeKeyboardWasShown = [[_tableView indexPathsForVisibleRows] objectAtIndex:0];
    [_tableView scrollToRowAtIndexPath:textFieldIndexPath atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
  }
}

- (void) scrollToOldPosition {
  [_tableView scrollToRowAtIndexPath:_topmostRowBeforeKeyboardWasShown atScrollPosition:UITableViewScrollPositionTop animated:YES];
}

- (void)keyboardWillHide:(NSNotification*)notification {
  if ([self currentFirstResponder] != nil) {

    NSDictionary* userInfo = [notification userInfo];

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[[userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue]];
    _tableView.frame = self.view.bounds;
    [UIView commitAnimations];

    [self performSelector:@selector(scrollToOldPosition) withObject:nil afterDelay:0.1];
  }
}   

@end

2011-08-03 02:35:10

其他回答

结合并填写几个答案(特别是Ortwin Gentz，用户98013)和另一篇文章中的空白，这将适用于iPad上的SDK 4.3的纵向或横向模式:

@implementation UIView (FindFirstResponder)
- (UIResponder *)findFirstResponder
{
  if (self.isFirstResponder) {        
    return self;     
  }

  for (UIView *subView in self.subviews) {
    UIResponder *firstResponder = [subView findFirstResponder];
    if (firstResponder != nil) {
      return firstResponder;
    }
  }

  return nil;
}
@end

@implementation MyViewController

- (UIResponder *)currentFirstResponder {
  return [self.view findFirstResponder];
}

- (IBAction)editingEnded:sender {
  [sender resignFirstResponder];
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {
  [textField resignFirstResponder];
  return NO;
}

- (void)textFieldDidBeginEditing:(UITextField *)textField {
  UITableViewCell *cell = (UITableViewCell*) [[textField superview] superview];
  [_tableView scrollToRowAtIndexPath:[_tableView indexPathForCell:cell] atScrollPosition:UITableViewScrollPositionTop animated:YES];
}

- (void)keyboardWillShow:(NSNotification*)notification {
  if ([self currentFirstResponder] != nil) {
    NSDictionary* userInfo = [notification userInfo];

    // we don't use SDK constants here to be universally compatible with all SDKs ≥ 3.0
    NSValue* keyboardFrameValue = [userInfo objectForKey:@"UIKeyboardBoundsUserInfoKey"];
    if (!keyboardFrameValue) {
      keyboardFrameValue = [userInfo objectForKey:@"UIKeyboardFrameEndUserInfoKey"];
    }

    // Reduce the tableView height by the part of the keyboard that actually covers the tableView
    CGRect windowRect = [[UIApplication sharedApplication] keyWindow].bounds;
    CGRect viewRectAbsolute = [_tableView convertRect:_tableView.bounds toView:[[UIApplication sharedApplication] keyWindow]];
    CGRect frame = _tableView.frame;
    if (UIInterfaceOrientationLandscapeLeft == self.interfaceOrientation ||UIInterfaceOrientationLandscapeRight == self.interfaceOrientation ) {
      windowRect = CGRectMake(windowRect.origin.y, windowRect.origin.x, windowRect.size.height, windowRect.size.width);
      viewRectAbsolute = CGRectMake(viewRectAbsolute.origin.y, viewRectAbsolute.origin.x, viewRectAbsolute.size.height, viewRectAbsolute.size.width);
    }
    frame.size.height -= [keyboardFrameValue CGRectValue].size.height - CGRectGetMaxY(windowRect) + CGRectGetMaxY(viewRectAbsolute);

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[[userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue]];
    _tableView.frame = frame;
    [UIView commitAnimations];

    UITableViewCell *textFieldCell = (id)((UITextField *)self.currentFirstResponder).superview.superview;
    NSIndexPath *textFieldIndexPath = [_tableView indexPathForCell:textFieldCell];

    // iOS 3 sends hide and show notifications right after each other
    // when switching between textFields, so cancel -scrollToOldPosition requests
    [NSObject cancelPreviousPerformRequestsWithTarget:self];
    _topmostRowBeforeKeyboardWasShown = [[_tableView indexPathsForVisibleRows] objectAtIndex:0];
    [_tableView scrollToRowAtIndexPath:textFieldIndexPath atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
  }
}

- (void) scrollToOldPosition {
  [_tableView scrollToRowAtIndexPath:_topmostRowBeforeKeyboardWasShown atScrollPosition:UITableViewScrollPositionTop animated:YES];
}

- (void)keyboardWillHide:(NSNotification*)notification {
  if ([self currentFirstResponder] != nil) {

    NSDictionary* userInfo = [notification userInfo];

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[[userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue]];
    _tableView.frame = self.view.bounds;
    [UIView commitAnimations];

    [self performSelector:@selector(scrollToOldPosition) withObject:nil afterDelay:0.1];
  }
}   

@end

2011-08-03 02:35:10

非常有趣的讨论线程，我也面临着同样的问题，可能更糟糕的一个原因

我正在使用一个自定义单元格和文本字段在里面。我不得不使用UIViewController来满足我的要求，所以不能利用UITableViewController。我有过滤/排序标准在我的表格单元格，即你的单元格不断改变和跟踪indexpath和所有将没有帮助。

所以阅读这里的帖子并实现我的版本，这帮助我在iPad的横屏模式下提升我的内容。这里是代码(这不是傻瓜证明，但它修复了我的问题) 首先，你需要在你的自定义单元格类中有一个委托，在编辑开始时，将文本字段发送到你的视图控制器，并设置activefield = theTextField

//只处理横向模式

- (void)keyboardWasShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbValue = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
    CGRect aRect = myTable.frame;

    CGSize kbSize = CGSizeMake(kbValue.height, kbValue.width);

    aRect.size.height -= kbSize.height+50;
// This will the exact rect in which your textfield is present
        CGRect rect =  [myTable convertRect:activeField.bounds fromView:activeField];
// Scroll up only if required
    if (!CGRectContainsPoint(aRect, rect.origin) ) {


            [myTable setContentOffset:CGPointMake(0.0, rect.origin.y) animated:YES];

    }


}

//当发送UIKeyboardWillHideNotification时调用

- (void)keyboardWillHide:(NSNotification*)aNotification
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    myTable.contentInset = contentInsets;
    myTable.scrollIndicatorInsets = contentInsets;
    NSDictionary* info = [aNotification userInfo];
    CGSize kbValue = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
    CGSize kbSize = CGSizeMake(kbValue.height, kbValue.width);
    CGRect bkgndRect = activeField.superview.frame;
    bkgndRect.size.height += kbSize.height;
    [activeField.superview setFrame:bkgndRect];
    [myTable setContentOffset:CGPointMake(0.0, 10.0) animated:YES];
}

-anoop4real

2012-07-17 17:11:11

以下是我如何做到这一点的，这是Sam Ho和Marcel W的回答，以及我自己对蹩脚代码的一些错误修复。我用的是UITableViewController。当键盘显示时，表格现在可以正确地调整大小。

1)在viewDidLoad我添加:

self.tableView.autoresizingMask = UIViewAutoresizingFlexibleHeight;

2)我忘记在viewWillAppear和awakeFromNib中调用超等价物。我把这些加回来了。

2012-07-26 17:18:59

UITableViewController会自动进行滚动。与使用UIViewController相比的区别是，当使用TableViewController时，你必须通过使用NavigationController以编程方式创建navbar - buttonitem。

2011-03-20 19:59:48

如果你的UITableView是由UITableViewController的子类管理的，而不是UITableView，并且文本字段委托是UITableViewController，它应该自动管理所有的滚动——所有这些其他注释在实践中是很难实现的。

有关一个好例子，请参阅apple示例代码项目:TaggedLocations。

你可以看到它自动滚动，但似乎没有任何代码做到这一点。该项目还具有自定义表视图单元格，因此，如果使用它作为指南构建应用程序，应该会得到预期的结果。