插入动态单元格并滚动到底部时,Tableview滞后

时间:2018-09-06 08:20:36

标签: swift performance uitableview smooth-scrolling reloadrows

我正在制作一个聊天机器人应用程序,其中我在表视图中添加了不同类型的单元格(具有动态高度),添加后,我滚动到底部。

当表格视图的内容大小小于屏幕高度时,添加单元格没有问题。但是,当tableview内容的大小必须增加(在屏幕外部)时,添加单元格的时间就很漫长,在我的旧iPad(iOS 10)上,单元格甚至无法正确显示(部分被切除)。有人可以帮我吗?

单击单元格选项后,我进行网络呼叫以获取新消息。通过该调用的结果,我填写了表格视图。

func ask(sessionId: String, question: String, retry : Bool, completion : @escaping CompletionBlock) {
    Alamofire.request(url!, method: .get, parameters: params, encoding: URLEncoding.default, headers: self.defaultHeaders).responseJSON { response in
            switch response.result {
            case .success(let results):
                completion(.success, results as? NSObject)
                break
            case .failure:
                completion(.error, nil)
                break
            }
        }
}

调用成功后,并将数据对象添加到其中包含新消息的数组中,我将在此部分添加新单元格:

func insertRowChatView(chatContent: [ChatMessage]) {
    if chatContent.count > self.chatMessageArray.count {
        self.chatMessageArray = chatContent

        let indexPath: IndexPath = IndexPath(row: self.chatMessageArray.count - 1, section: 0)
        self.tableView.insertRows(at: [indexPath], with: .none)
        self.tableView.reloadRows(at: [indexPath], with: .none)
        self.tableView.scrollToRow(at: indexPath, at: .bottom, animated: true)
    }
}

还有我的cellforrowatindex路径代码:

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    if (chatMessageArray.count) > indexPath.row {
        if chatMessageArray[indexPath.row].dialogOptions != nil && chatMessageArray[indexPath.row].dialogOptions!.count > 0 {
            // Dialogoptions cell
            let cell = tableView.dequeueReusableCell(withIdentifier: "ChatDialogOptionCell", for: indexPath as IndexPath) as! ChatDialogOptionCell
            cell.delegate = self
            cell.setupCell(dialogOptions: chatMessageArray[indexPath.row].dialogOptions!, text: chatMessageArray[indexPath.row].text!, lastItem: chatMessageArray[indexPath.row].lastItem)
            return cell
        } else if chatMessageArray[indexPath.row].links != nil && chatMessageArray[indexPath.row].links!.count > 0 {
            // Links cell
            let cell = tableView.dequeueReusableCell(withIdentifier: "ChatLinkCell", for: indexPath as IndexPath) as! ChatLinkCell
            cell.delegate = self
            cell.setupCell(links: chatMessageArray[indexPath.row].links!, text: chatMessageArray[indexPath.row].text!, lastItem: chatMessageArray[indexPath.row].lastItem)
            return cell
        } else if chatMessageArray[indexPath.row].text != nil && chatMessageArray[indexPath.row].text != "" {
            // Text only
            let cell = tableView.dequeueReusableCell(withIdentifier: "ChatTextOnlyCell", for: indexPath as IndexPath) as! ChatTextOnlyCell
            cell.setupCell(text: chatMessageArray[indexPath.row].text!, askedByUser: chatMessageArray[indexPath.row].askedByUser, lastItem: chatMessageArray[indexPath.row].lastItem)
            return cell
        } else {
            // Typing indicator
            let cell = tableView.dequeueReusableCell(withIdentifier: "ChatTypingIndicatorCell", for: indexPath as IndexPath) as! ChatTypingIndicatorCell
            cell.setupCell()
            return cell
        }
    }

    let cell = UITableViewCell()
    cell.selectionStyle = UITableViewCellSelectionStyle.none
    return cell
}

我的代码是否存在问题,导致此性能问题?

感谢您的帮助!

0 个答案:

没有答案