拉动后滚动到屏幕顶部以在表格视图中刷新

Question

我有一个聊天应用程序，正在其中以表格视图显示消息。当我拉动刷新并在顶部显示更多消息时，我希望保留在触发拉动刷新的同一屏幕上，即不跳转。以下代码无效，并且向下滚动。

func refresh() {
    currentPage = currentPage + 1

    if currentPage <= totalPages {
        fetchMessaes(page: self.currentPage, completed: {

            self.messageArray.append(contentsOf: self.fetchedMessages!.messages!)

            // Sort message by ID so that latest message appear at the bottom.
            let sortedArray = self.messageArray.sorted(by: {$0.id! < $1.id!})
            self.fetchedMessages = sortedArray

            self.messagesTable.reloadData()

            // Scroll to the last row of recently loaded messages
            DispatchQueue.main.async {
                let index = IndexPath(row: 0, section: 0)
                self.messagesTable.scrollToRow(at: index, at: .top, animated: false)
            }
        })
    }
    refreshControl.endRefreshing()
}

Answer 1

能否请您将表视图reloadData()放在main queue内并尝试？

DispatchQueue.main.async {
    self.messagesTable.reloadData()
    let index = IndexPath(row: 0, section: 0)
    self.messagesTable.scrollToRow(at: index, at: .top, animated: false)
}