ios - 最后两个单元格之间奇怪的 UITableViewCell 间隙

Question

我有一个自定义 UITableViewCell Card 样式的动态高度，它的空间在应用程序中是恒定的。我正在使用 Storyboard ，并且在 UINavigationBar 下方有 UIToolbar。

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    if (!_listOfMessages) {
        return 0;
    }
    else if (_unreadMessages && [self.segmentControl selectedSegmentIndex] == 0)
        return _unreadMessages.count;
    else
        return _listOfMessages.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    WCFeedItem *item;

    if ([self.segmentControl selectedSegmentIndex] == 0) {
        item = _unreadMessages[indexPath.row];
    }
    else {
        item = _listOfMessages[indexPath.row];
    }

    RKCardInboxCell *cell = (RKCardInboxCell *)[tableView dequeueReusableCellWithIdentifier:@"RKCardInboxCell"];

    // Configure the cell...
    if (cell == nil) {
        cell = [[RKCardInboxCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"RKCardInboxCell"];
    }
    else {
        [[[cell.contentView viewWithTag:99] viewWithTag:97] removeFromSuperview];
        cell.cardView.backgroundColor = [UIColor whiteColor];
    }

    [cell layoutSubviews];

    [cell.profileImage setImageWithURLRequest:[[NSURLRequest alloc] initWithURL:[NSURL URLWithString:item.person.avatar_feed]] placeholderImage:[UIImage imageNamed:@"loading"] success:
     ^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
         cell.profileImage.image = image;
     } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
     }];

    [cell setItem:item];


    cell.titleLabel.lineBreakMode = NSLineBreakByWordWrapping;
    cell.titleLabel.numberOfLines = 0;

    CGRect expectedLabelSize = [item.summary boundingRectWithSize:CGSizeMake(268, MAXFLOAT)
                                                          options:NSStringDrawingUsesLineFragmentOrigin
                                                       attributes:@{NSFontAttributeName:cell.titleLabel.font}
                                                          context:nil];

    //        NSLog(@"size %@", NSStringFromCGSize(expectedLabelSize.size));
    CGRect newFrame = cell.titleLabel.frame;
    newFrame.size.height = expectedLabelSize.size.height;
    cell.titleLabel.frame = newFrame;

    cell.titleLabel.text = item.summary;
    cell.nameLabel.text =  item.person.name;
    cell.descriptionLabel.text = item.messageTo;
    [cell.timeButton setTitle:item.date forState:UIControlStateNormal];

    if (item.isUnseen) {
        cell.cardView.backgroundColor = [UIColor colorWithRed:0.94 green:0.97 blue:1 alpha:1];

        UIView *circleView = [[UIView alloc] initWithFrame:CGRectMake(10,20,10,10)];
        circleView.alpha = 0.5;
        circleView.layer.cornerRadius = 5;
        circleView.backgroundColor = [UIColor colorWithRed:0 green:0.2 blue:0.4 alpha:1.0];
        circleView.tag = 97;
        CGRect timeLabel = [[cell.contentView viewWithTag:99] viewWithTag:98].frame;
        circleView.center = CGPointMake((timeLabel.origin.x + timeLabel.size.width) - circleView.frame.size.width, timeLabel.origin.y + timeLabel.size.height + circleView.frame.size.height);
        [[cell.contentView viewWithTag:99] addSubview:circleView];
        //[cell bringSubviewToFront:circleView];
    }


    cell.cardView.frame = CGRectMake(10, 5, 300, 160-8+expectedLabelSize.size.height-5);

    return cell;

}


- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{

    UIFont *font = [UIFont systemFontOfSize:13];

    NSString *aboutText = [_listOfMessages[indexPath.row] summary];


    // ios 7 only
    CGRect boundingRect = [aboutText boundingRectWithSize:CGSizeMake(268, MAXFLOAT)
                                                  options:NSStringDrawingUsesLineFragmentOrigin
                                               attributes:@{NSFontAttributeName:font}
                                                  context:nil];

    CGSize boundingSize = boundingRect.size;
    // end ios7 only

//    [cardSizeArray addObject:[NSNumber numberWithInt:160-8+boundingSize.height]];

    return (160-8+boundingSize.height);
}

Answer 1

是因为cardView宽 300 点，但 heightForRowAtIndexPath使用268点？看起来有问题的行的文本可能会在 268 处换成两行，但在 300 处只有一行。没有看到 RKCardInboxCell 的布局代码很难确定。

顺便说一句，像这样的硬编码宽度将难以支持更宽的设备，如 iPhone 6 和 6 Plus。