表视图单元格的样式分隔符

Question

我的willDisplayCell函数中有以下代码

//bottom border
UIView* bottomBorderView = [[UIView alloc] initWithFrame:CGRectMake(0, cell.frame.size.height-1, cell.frame.size.width, 1)];/// change size as you need.
bottomBorderView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"dot.png"]];// you can also put image here
[cell.contentView addSubview:bottomBorderView];

它在iOS7中工作得很好，但自从我更新Xcode并开始在iOS8上测试应用程序以来，边框显示不正确。我无法弄清楚导致这个问题的变化。滚动越多，问题似乎越来越严重。