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

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。

其他回答

如果你使用uitableview来放置你的文本字段(来自Jeff Lamarche),你可以像这样使用委托方法滚动tableview。

(注意:我的文本字段存储在一个数组中,索引与表视图中的行相同)

- (void) textFieldDidBeginEditing:(UITextField *)textField
    {

        int index;
        for(UITextField *aField in textFields){

            if (textField == aField){
                index = [textFields indexOfObject:aField]-1;
            }
        }

         if(index >= 0) 
            [self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:index inSection:0] atScrollPosition:UITableViewScrollPositionTop animated:YES];

        [super textFieldDidBeginEditing:textField];
    }

执行滚动的函数可以简单得多:

- (void) textFieldDidBeginEditing:(UITextField *)textField {
    UITableViewCell *cell;

    if (floor(NSFoundationVersionNumber) <= NSFoundationVersionNumber_iOS_6_1) {
    // Load resources for iOS 6.1 or earlier
        cell = (UITableViewCell *) textField.superview.superview;

    } else {
        // Load resources for iOS 7 or later
        cell = (UITableViewCell *) textField.superview.superview.superview; 
       // TextField -> UITableVieCellContentView -> (in iOS 7!)ScrollView -> Cell!
    }
    [tView scrollToRowAtIndexPath:[tView indexPathForCell:cell] atScrollPosition:UITableViewScrollPositionTop animated:YES];
}

就是这样。根本不需要计算。

在Swift中的一个例子,使用从UITableViewCell中获取UITextField的indexPath的文本字段的确切点:

func textFieldDidBeginEditing(textField: UITextField) {
    let pointInTable = textField.convertPoint(textField.bounds.origin, toView: self.accountsTableView)
    let textFieldIndexPath = self.accountsTableView.indexPathForRowAtPoint(pointInTable)
    accountsTableView.scrollToRowAtIndexPath(textFieldIndexPath!, atScrollPosition: .Top, animated: true)
}

键盘通知可以工作,但苹果的示例代码假设滚动视图是窗口的根视图。通常情况并非如此。您必须补偿标签栏等,以获得正确的偏移量。

这比听起来容易。下面是我在UITableViewController中使用的代码。它有两个实例变量,hiddenRect和keyboardshow。

// Called when the UIKeyboardDidShowNotification is sent.
- (void)keyboardWasShown:(NSNotification*)aNotification {
    if (keyboardShown)
        return;

    NSDictionary* info = [aNotification userInfo];

    // Get the frame of the keyboard.
    NSValue *centerValue = [info objectForKey:UIKeyboardCenterEndUserInfoKey];
    NSValue *boundsValue = [info objectForKey:UIKeyboardBoundsUserInfoKey];
    CGPoint keyboardCenter = [centerValue CGPointValue];
    CGRect keyboardBounds = [boundsValue CGRectValue];
    CGPoint keyboardOrigin = CGPointMake(keyboardCenter.x - keyboardBounds.size.width / 2.0,
                                         keyboardCenter.y - keyboardBounds.size.height / 2.0);
    CGRect keyboardScreenFrame = { keyboardOrigin, keyboardBounds.size };


    // Resize the scroll view.
    UIScrollView *scrollView = (UIScrollView *) self.tableView;
    CGRect viewFrame = scrollView.frame;
    CGRect keyboardFrame = [scrollView.superview convertRect:keyboardScreenFrame fromView:nil];
    hiddenRect = CGRectIntersection(viewFrame, keyboardFrame);

    CGRect remainder, slice;
    CGRectDivide(viewFrame, &slice, &remainder, CGRectGetHeight(hiddenRect), CGRectMaxYEdge);
    scrollView.frame = remainder;

    // Scroll the active text field into view.
    CGRect textFieldRect = [/* selected cell */ frame];
    [scrollView scrollRectToVisible:textFieldRect animated:YES];

    keyboardShown = YES;
}


// Called when the UIKeyboardDidHideNotification is sent
- (void)keyboardWasHidden:(NSNotification*)aNotification
{
    // Reset the height of the scroll view to its original value
    UIScrollView *scrollView = (UIScrollView *) self.tableView;
    CGRect viewFrame = [scrollView frame];
    scrollView.frame = CGRectUnion(viewFrame, hiddenRect);

    keyboardShown = NO;
}

这个解决方案为我工作,请注意这一行

[tableView setContentOffset:CGPointMake(0.0, activeField.frame.origin.y-kbSize.height+160) animated:YES];

您可以更改160值以使其与您的工作相匹配

- (void)keyboardWasShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
    CGRect bkgndRect = activeField.superview.frame;
                        bkgndRect.size.height += kbSize.height;
     [activeField.superview setFrame:bkgndRect];
     [tableView setContentOffset:CGPointMake(0.0, activeField.frame.origin.y-kbSize.height+160) animated:YES];
}

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
   activeField = textField;
}
-(void)textFieldDidEndEditing:(UITextField *)textField
 {
     activeField = nil;
 }
// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    tableView.contentInset = contentInsets;
    tableView.scrollIndicatorInsets = contentInsets;
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
    CGRect bkgndRect = activeField.superview.frame;
    //bkgndRect.size.height += kbSize.height;
    [activeField.superview setFrame:bkgndRect];
    [tableView setContentOffset:CGPointMake(0.0, activeField.frame.origin.y-kbSize.height) animated:YES];
}