Laggy UITableViewController

Question

我有UITableViewController 1000行。每个单元格都包含用属性字符串填充的标签。单元格是自我调整单元格并且在estimatedHeightForRowAtIndexPath中估计不正确所以我没有使用它（我不知道为什么我的估计导致滞后，我使用NSSting.boundingRectWithSize进行估计）。我在我的视图底部有UISlider作为SeekBar，当我寻找太多中间页面主线程变得忙于cellForRowAtIndexPath时，甚至我无法显示等待进度条，如HUD进度。

这是我的cellForRowAtIndexPath：

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCellWithIdentifier("Aya Cell") as! AyaCell
    let detail = API.readingDetail[indexPath.row % API.readingDetail.count]


    cell.backgroundColor = backgroundColor

    switch detail {
    case .Persian:

        let text = translations.suras[self.sura.index-1].ayas[indexPath.row / API.readingDetail.count].text
        var textBackground = UIColor.clearColor()
        if translations.suras[self.sura.index-1].ayas[indexPath.row / API.readingDetail.count].shouldSelected == true {
            textBackground = UIColor.yellowColor()
        }

        let attributedText = NSMutableAttributedString(string: text, attributes: [NSForegroundColorAttributeName: persianTextColor, NSFontAttributeName: AyaPersianFont!, NSBackgroundColorAttributeName: backgroundColor])
        attributedText.appendAttributedString(NSAttributedString(string: " (\((indexPath.row / API.readingDetail.count+1).toArabicDigit()))", attributes: [NSForegroundColorAttributeName: MojezeRedColor, NSFontAttributeName:UIFont(name: "XNazanin", size: AyaFont!.pointSize*0.65)!, NSParagraphStyleAttributeName: AyaParagraphStyle]))
        cell.ayaTextLabel.attributedText = attributedText

    case .Arabic:
        let text = self.sura.ayas[indexPath.row / API.readingDetail.count].text

        var textBackground = UIColor.clearColor()
        if self.sura.ayas[indexPath.row / API.readingDetail.count].shouldSelected == true {
            textBackground = UIColor.yellowColor()
        }

        let attributedText = NSMutableAttributedString(string: text, attributes: [NSForegroundColorAttributeName: arabicTextColor, NSFontAttributeName: AyaFont!, NSBackgroundColorAttributeName: textBackground])
        attributedText.appendAttributedString(NSAttributedString(string: " ﴿\((indexPath.row / API.readingDetail.count+1).toArabicDigit())﴾", attributes: [NSForegroundColorAttributeName: MojezeRedColor, NSFontAttributeName:UIFont(name: "XNazanin", size: AyaFont!.pointSize*0.65)!, NSParagraphStyleAttributeName: AyaParagraphStyle]))
        cell.ayaTextLabel.attributedText = attributedText

    }

    return cell
}

有没有解决方案？