iphone - 使用 NSString sizeWithFont :constrainedToSize:lineBreakMode: 调整大小时，表格单元格最后一行被截断

Question

当使用以下代码调整表格行的大小时，无论有多少行，最后一行文本总是被截断。但是添加了空白，看起来足以容纳文本。

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [self tableView:tableView cellForRowAtIndexPath:indexPath];
    CGFloat restOfTheCellHeight = tableView.rowHeight - cell.detailTextLabel.frame.size.height;
    CGSize constrainedSize = CGSizeMake(cell.detailTextLabel.frame.size.width, CGFLOAT_MAX);
    CGSize textHeight = [cell.detailTextLabel.text sizeWithFont:cell.detailTextLabel.font constrainedToSize:constrainedSize lineBreakMode:cell.detailTextLabel.lineBreakMode];
    CGFloat newCellHeight = (textHeight.height + restOfTheCellHeight);
    if (tableView.rowHeight > newCellHeight) {
        newCellHeight = tableView.rowHeight;
    }
    return newCellHeight;
}

这是 cellForRowAtIndexPath 中的代码:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    CustomCellTableRowTypeSingleLineValueSmallLabel *cell = (CustomCellTableRowTypeSingleLineValueSmallLabel *)[tableView dequeueReusableCellWithIdentifier:@"CellTypeMultiLineLabelInCellSmallCell"];

    if (cell == nil) {
        NSArray *xibObjects = [[NSBundle mainBundle] loadNibNamed:@"CustomCellTableRowTypeSingleLine" owner:nil options:nil];
        for(id currentObject in xibObjects) {
            if([currentObject isKindOfClass:[CustomCellTableRowTypeSingleLineValueSmallLabel class]]){
                cell = (CustomCellTableRowTypeSingleLineValueSmallLabel *)currentObject;
            }
        }
        cell.accessoryType = UITableViewCellAccessoryNone;
        cell.editingAccessoryType = UITableViewCellAccessoryDisclosureIndicator;
    }   

    cell.detailTextLabel.lineBreakMode = UILineBreakModeWordWrap;
    cell.detailTextLabel.numberOfLines = 0;

    cell.detailTextLabel.text = self.attributeStringValue;
    cell.textLabel.text = self.rowLabel;

    return cell;
}

有什么想法吗？

Answer 1

您需要调用 [cell.detailTextLabel sizeToFit] 以便标签在 cellForRowAtIndexPath 中实际调整大小。它不会因为您将 numberOfLines 设置为 0 而自行调整大小。参见 this question and read its answers以获得更多说明。