下面是Simons对Swift 3的简短回答。还允许切换单元格的选择

var cellIsSelected: IndexPath?


  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    cellIsSelected = cellIsSelected == indexPath ? nil : indexPath
    tableView.beginUpdates()
    tableView.endUpdates()
  }


  func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    if cellIsSelected == indexPath {
      return 250
    }
    return 65
  }

是的，这是可能的。

UITableView有一个委托方法didSelectRowAtIndexPath

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [UIView animateWithDuration:.6
                          delay:0
         usingSpringWithDamping:UIViewAnimationOptionBeginFromCurrentState
          initialSpringVelocity:0
                        options:UIViewAnimationOptionBeginFromCurrentState animations:^{

                            cellindex = [NSIndexPath indexPathForRow:indexPath.row inSection:indexPath.section];
                            NSArray* indexArray = [NSArray arrayWithObjects:indexPath, nil];
                            [violatedTableView beginUpdates];
                            [violatedTableView reloadRowsAtIndexPaths:indexArray withRowAnimation:UITableViewRowAnimationAutomatic];
                            [violatedTableView endUpdates];
                        }
                     completion:^(BOOL finished) {
    }];
}

但在你的情况下，如果用户滚动并选择不同的单元格，那么你需要有最后一个选定的单元格来收缩和扩展当前选定的单元格reloadRowsAtIndexPaths:调用highightforrowatindexpath:因此相应地处理。

下面是我的自定义UITableView子类的代码，它在表格单元展开UITextView，而无需重新加载(和丢失键盘焦点):

- (void)textViewDidChange:(UITextView *)textView {
    CGFloat textHeight = [textView sizeThatFits:CGSizeMake(self.width, MAXFLOAT)].height;
    // Check, if text height changed
    if (self.previousTextHeight != textHeight && self.previousTextHeight > 0) {
        [self beginUpdates];

        // Calculate difference in height
        CGFloat difference = textHeight - self.previousTextHeight;

        // Update currently editing cell's height
        CGRect editingCellFrame = self.editingCell.frame;
        editingCellFrame.size.height += difference;
        self.editingCell.frame = editingCellFrame;

        // Update UITableView contentSize
        self.contentSize = CGSizeMake(self.contentSize.width, self.contentSize.height + difference);

        // Scroll to bottom if cell is at the end of the table
        if (self.editingNoteInEndOfTable) {
            self.contentOffset = CGPointMake(self.contentOffset.x, self.contentOffset.y + difference);
        } else {
            // Update all next to editing cells
            NSInteger editingCellIndex = [self.visibleCells indexOfObject:self.editingCell];
            for (NSInteger i = editingCellIndex; i < self.visibleCells.count; i++) {
                UITableViewCell *cell = self.visibleCells[i];
                CGRect cellFrame = cell.frame;
                cellFrame.origin.y += difference;
                cell.frame = cellFrame;
            }
        }
        [self endUpdates];
    }
    self.previousTextHeight = textHeight;
}

而不是beginUpdates()/ endpdates()，建议调用现在是:

tableView.performBatchUpdates(nil, completion: nil)

关于beginUpdates/ endpdates，苹果说:“尽可能使用performBatchUpdates(_:completion:)方法而不是这个方法。”

参见:https://developer.apple.com/documentation/uikit/uitableview/1614908-beginupdates

这是为了按索引展开行:

@property (nonatomic) NSIndexPath *expandIndexPath;
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath*)indexPath
{
if ([indexPath isEqual:self.expandedIndexPath])
    return 100;

return 44;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
NSMutableArray *modifiedRows = [NSMutableArray array];
if ([indexPath isEqual:self.expandIndexPath]) {
    [modifiedRows addObject:self.expandIndexPath];
    self.expandIndexPath = nil;
} else {
    if (self.expandedIndexPath)
        [modifiedRows addObject:self.expandIndexPath];

    self.expandIndexPath = indexPath;
    [modifiedRows addObject:indexPath];
}

// This will animate updating the row sizes
[tableView reloadRowsAtIndexPaths:modifiedRows withRowAnimation:UITableViewRowAnimationAutomatic];

// Preserve the deselection animation (if desired)
[tableView selectRowAtIndexPath:indexPath animated:NO scrollPosition:UITableViewScrollPositionNone];
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:ViewControllerCellReuseIdentifier];
    cell.textLabel.text = [NSString stringWithFormat:@"I'm cell %ld:%ld", (long)indexPath.section, (long)indexPath.row];

return cell;
}

BOOL flag;

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    flag = !flag;
    [tableView beginUpdates];
    [tableView reloadRowsAtIndexPaths:@[indexPath] 
                     withRowAnimation:UITableViewRowAnimationAutomatic];
    [tableView endUpdates];
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return YES == flag ? 20 : 40;
}