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

不需要任何计算,使用下面的代码,它将工作: 这段代码我用在我的自定义UITableviewcell,它是工作的:

override func viewDidLoad() {
super.viewDidLoad()

NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)

NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)}


func keyboardWillShow(_ notification:Notification) {

if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
    tableView.contentInset = UIEdgeInsetsMake(0, 0, keyboardSize.height, 0)
}}


func keyboardWillHide(_ notification:Notification) {

if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
    tableView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0)
}}

其他回答

因为你在一个表格中有文本字段,最好的方法是调整表格的大小——你需要设置tableView.frame的高度比键盘的大小小(我认为大约165像素),然后当键盘被关闭时再次展开它。

如果你不想让用户滚动,你也可以选择在那个时候禁用tableView的用户交互。

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。

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

在viewdidload

-(void)viewdidload{

[super viewdidload];

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

    -(void)keyboardWillChange:(NSNotification*)sender{

        NSLog(@"keyboardwillchange sender %@",sender);

float margin=0  // set your own topmargin


        CGFloat originY = [[sender.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].origin.y;


        if (originY >= self.view.frame.size.height){

            NSLog(@"keyboardclose");



            [tb_ setFrame:CGRectMake(0, margin, self.view.frame.size.width, self.view.frame.size.height-margin)];

        }else{

            NSLog(@"keyobard on");

            float adjustedHeight = self.view.frame.size.height - margin - (self.view.frame.size.height-originY);

            [tb_ setFrame:CGRectMake(0, margin, self.view.frame.size.width, adjustedHeight)];
        }







    }

我认为最好的方法是通过UITableViewController。

如果你想在UIViewController中创建一个UITableView,只需要用一个嵌入的UITableViewController创建一个ContentView,并在UIViewController的viedDidLoad中放入以下代码行:

self.tableView = ((UITableViewController*)self.childViewControllers[0]).tableView;
self.tableView.delegate = self;
self.tableView.dataSource = self;

容易,)