Flip-flopping text in tableview cells - ios

Question

I am having a peculiar problem when I refresh my tableview. (I am using UIRefreshControl.) If I were to slow-mo what is happening:
Suppose there are 3 cells visible, A, B, and C, in that order from top to bottom.
1) I pull down and the tableview shows that it is refreshing.
2) A gets the text that should go in B. B gets the text that should go in C. C is off-screen.
3) Refresh ends and the table snaps back into place.
4) Incorrect text lingers for a second or so.
5) Each cell's text flips to the right thing.
The flip-flopping is pretty annoying to look at visually. Anyway, I feel like this is the kind of issue that can be fixed with a line of code that I just don't know about.
Here are excerpts of my code:
Function called when refresh occurs (gets records from CloudKit):
func refreshTable(sender: UIRefreshControl) {
var postsPredicate = NSPredicate(format: "%K = %#", VISIBILITY_CODE, WORLD) // default
if sender.tag == 0 {
postsPredicate = NSPredicate(format: "%K = %#", VISIBILITY_CODE, WORLD)
}
else if sender.tag == 1 {
postsPredicate = NSPredicate(format: "%K = %#", VISIBILITY_CODE, PRIVATE)
}
else {
// report problem
}
let query = CKQuery(recordType: POST, predicate: postsPredicate)
let sort = NSSortDescriptor(key: "creationDate", ascending: false)
query.sortDescriptors = [sort]
self.db.perform(query, inZoneWith: nil) { records, error in
if error == nil {
self.list = [records!]
DispatchQueue.main.async(execute: {
self.postTableView.reloadData()
self.refreshControl.endRefreshing()
})
}
else {
if let error = error as? CKError {
print(error)
}
}
}
}
Here's my cellForRowAtIndexPath function:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if self.list.count == 1 && self.list[0].count == 0 {
let cell = tableView.dequeueReusableCell(withIdentifier: NO_POSTS, for: indexPath)
return cell
}
let post = self.list[indexPath.section][indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: POST_IN_FEED_CELL, for: indexPath)
if let postCell = cell as? PostInFeedTableViewCell {
// deleted the assignment of values to other UI elements in my custom cell
let predicate = NSPredicate(format: "%K = %#", LIBRARY_CODE, post.object(forKey: LIBRARY_CODE) as! String)
let query = CKQuery(recordType: LIBRARY_ITEM, predicate: predicate)
self.db.perform(query, inZoneWith: nil) { records, error in
if error == nil {
let libraryItem = records?[0]
DispatchQueue.main.async(execute: {
postCell.title.text = libraryItem?.object(forKey: NAME) as! String
})
}
else {
if let error = error as? CKError {
print(error)
}
}
}
}
return cell
}