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

我在做一些非常相似的事情它是通用的,不需要为你的代码计算特定的东西。 只需检查代码上的注释:

在MyUIViewController.h

@interface MyUIViewController: UIViewController <UITableViewDelegate, UITableViewDataSource>
{
     UITableView *myTableView;
     UITextField *actifText;
}

@property (nonatomic, retain) IBOutlet UITableView *myTableView;
@property (nonatomic, retain) IBOutlet UITextField *actifText;

- (IBAction)textFieldDidBeginEditing:(UITextField *)textField;
- (IBAction)textFieldDidEndEditing:(UITextField *)textField;

-(void) keyboardWillHide:(NSNotification *)note;
-(void) keyboardWillShow:(NSNotification *)note;

@end

在MyUIViewController.m

@implementation MyUIViewController

@synthesize myTableView;
@synthesize actifText;

- (void)viewDidLoad 
{
    // Register notification when the keyboard will be show
    [[NSNotificationCenter defaultCenter] addObserver:self
                                          selector:@selector(keyboardWillShow:)
                                          name:UIKeyboardWillShowNotification
                                          object:nil];

    // Register notification when the keyboard will be hide
    [[NSNotificationCenter defaultCenter] addObserver:self
                                          selector:@selector(keyboardWillHide:)
                                          name:UIKeyboardWillHideNotification
                                          object:nil];
}

// To be link with your TextField event "Editing Did Begin"
//  memoryze the current TextField
- (IBAction)textFieldDidBeginEditing:(UITextField *)textField
{
    self.actifText = textField;
}

// To be link with your TextField event "Editing Did End"
//  release current TextField
- (IBAction)textFieldDidEndEditing:(UITextField *)textField
{
    self.actifText = nil;
}

-(void) keyboardWillShow:(NSNotification *)note
{
    // Get the keyboard size
    CGRect keyboardBounds;
    [[note.userInfo valueForKey:UIKeyboardFrameBeginUserInfoKey] getValue: &keyboardBounds];

    // Detect orientation
    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];
    CGRect frame = self.myTableView.frame;

    // Start animation
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:0.3f];

    // Reduce size of the Table view 
    if (orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown)
        frame.size.height -= keyboardBounds.size.height;
    else 
        frame.size.height -= keyboardBounds.size.width;

    // Apply new size of table view
    self.myTableView.frame = frame;

    // Scroll the table view to see the TextField just above the keyboard
    if (self.actifText)
      {
        CGRect textFieldRect = [self.myTableView convertRect:self.actifText.bounds fromView:self.actifText];
        [self.myTableView scrollRectToVisible:textFieldRect animated:NO];
      }

    [UIView commitAnimations];
}

-(void) keyboardWillHide:(NSNotification *)note
{
    // Get the keyboard size
    CGRect keyboardBounds;
    [[note.userInfo valueForKey:UIKeyboardFrameBeginUserInfoKey] getValue: &keyboardBounds];

    // Detect orientation
    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];
    CGRect frame = self.myTableView.frame;

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:0.3f];

    // Increase size of the Table view 
    if (orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown)
        frame.size.height += keyboardBounds.size.height;
    else 
        frame.size.height += keyboardBounds.size.width;

    // Apply new size of table view
    self.myTableView.frame = frame;

    [UIView commitAnimations];
}

@end

Swift 1.2+版本:

class ViewController: UIViewController, UITextFieldDelegate {
    @IBOutlet weak var activeText: UITextField!
    @IBOutlet weak var tableView: UITableView!

    override func viewDidLoad() {
        NSNotificationCenter.defaultCenter().addObserver(self,
            selector: Selector("keyboardWillShow:"),
            name: UIKeyboardWillShowNotification,
            object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self,
            selector: Selector("keyboardWillHide:"),
            name: UIKeyboardWillHideNotification,
            object: nil)
    }

    func textFieldDidBeginEditing(textField: UITextField) {
        activeText = textField
    }

    func textFieldDidEndEditing(textField: UITextField) {
        activeText = nil
    }

    func keyboardWillShow(note: NSNotification) {
        if let keyboardSize = (note.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
            var frame = tableView.frame
            UIView.beginAnimations(nil, context: nil)
            UIView.setAnimationBeginsFromCurrentState(true)
            UIView.setAnimationDuration(0.3)
            frame.size.height -= keyboardSize.height
            tableView.frame = frame
            if activeText != nil {
                let rect = tableView.convertRect(activeText.bounds, fromView: activeText)
                tableView.scrollRectToVisible(rect, animated: false)
            }
            UIView.commitAnimations()
        }
    }

    func keyboardWillHide(note: NSNotification) {
        if let keyboardSize = (note.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
            var frame = tableView.frame
            UIView.beginAnimations(nil, context: nil)
            UIView.setAnimationBeginsFromCurrentState(true)
            UIView.setAnimationDuration(0.3)
            frame.size.height += keyboardSize.height
            tableView.frame = frame
            UIView.commitAnimations()
        }
    }
}

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

我尝试了几乎相同的方法,并提出了一个更简单、更小的代码。 我创建了一个IBOutlet iTextView,并与IB中的UITextView相关联。

 -(void)keyboardWillShow:(NSNotification *)notification
    {
        NSLog(@"Keyboard");
        CGRect keyFrame = [[[notification userInfo]objectForKey:UIKeyboardFrameEndUserInfoKey]CGRectValue];

        [UIView beginAnimations:@"resize view" context:nil];
        [UIView setAnimationCurve:1];
        [UIView setAnimationDuration:1.0];
        CGRect frame = iTableView.frame;
        frame.size.height = frame.size.height -  keyFrame.size.height;
        iTableView.frame = frame;
        [iTableView scrollRectToVisible:frame animated:YES];
        [UIView commitAnimations];

    }

我刚刚发现另一个bug时使用UITableViewController。当键盘出现时,它不会自动滚动。我注意到这是因为contentInsetAdjustmentBehavior = .never在UITableView上。

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)
}}

我的方法:

我首先子类化UITextField并添加一个indexPath属性。在牢房里因为…方法我交出indexPath属性。

然后我添加以下代码:

UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:textField.indexPath];

CGPoint cellPoint = [cell convertPoint:textField.center toView:self.tableView];
[UIView animateWithDuration:0.3 animations:^(void){self.tableView.contentOffset = CGPointMake(0, cellPoint.y-50);}];

textFieldShould/WillBegin…等等。

当键盘消失时,你必须反转它:

[UIView animateWithDuration:0.3 animations:^(void){self.tableView.contentOffset = CGPointMake(0, 0);}];