Swift and Parse - Message app, cannot display username within Xcode 6.3 - ios

Question

I have some issue to display the 'author's username of each posts in my TableViewController.
It actually display the current user's username for all display posts, how to display each poster's username ?
I'm using Xcode 6.3 and Parse.com API.
The timeLabel is displayed correctly, but the userLabel display the current user who is logged in instead of the author of the post.
If I logged out and login with a different username all the userLabel change to the new user. The debug console display Optional("theNameOfTheCurrentUser") as many times as there are posts displayed.
Parse host 2 DB one for users (User) and one for posts (Poemes), there is a pointer in Poemes table to the specific user.
I update to Xcode 6.3 lately and had an error on var findLover:PFQuery = PFUser.query()
Value of optional type 'PFQuery?' not unwrapped
I add the exclamation mark (!) at the end of this line, which remove the error, is this causing the issue ?
I read Parse documentation and follow some exemples but looks like I'm a bit lost here, any help and suggestions will be highly appreciated, thanks.
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell:DisplayTableViewCell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! DisplayTableViewCell
let poeme:PFObject = self.timelineData.objectAtIndex(indexPath.row) as! PFObject
cell.poemeLabel.text = poeme.objectForKey("content") as? String
var dateFormatter:NSDateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "MM-dd HH:mm"
cell.timeLabel.text = dateFormatter.stringFromDate(poeme.createdAt!)
var findUser:PFQuery = PFUser.query()!
findUser.findObjectsInBackgroundWithBlock {
(objects, error)->Void in
if var objects = objects {
let author:PFUser = (objects as NSArray).lastObject as! PFUser
cell.userLabel.text = author.username
println(author.username)
})
}
return cell
}

Answer 1

The function findUser.findObjectsInBackgroundWithBlock happens in the background, while the main thread still running, so by the time you get the response from parse with the values you need the cell you are trying to return in the function is long gone.
The easiest way to fix it is to fetch all the data you need before hand and safe it in a array and use this array to populate the cell.

Answer 2

Finally get it work for Xcode 6.3.2 changes, here is the result :
unwrap and optional seams to be my main problem :
override func tableView(tableView: UITableView?, cellForRowAtIndexPath indexPath: NSIndexPath?) -> UITableViewCell {
let cell:DisplayTableViewCell = tableView!.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath!) as! DisplayTableViewCell
let poeme:PFObject = self.timelineData.objectAtIndex(indexPath!.row) as! PFObject
cell.poemeLabel.text = poeme.objectForKey("content") as! String
var dateFormatter:NSDateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "MM-dd HH:mm"
cell.timeLabel.text = dateFormatter.stringFromDate(poeme.createdAt!)
var findUser:PFQuery = PFUser.query()!
findUser.whereKey("objectId", equalTo: poeme.objectForKey("user")!.objectId!!)
findLover.findObjectsInBackgroundWithBlock {
(objects, error)->Void in
if var objects = objects {
let author:PFUser = (objects as NSArray).lastObject as! PFUser
cell.userLabel.text = author.username
println(author.username)
})
}
}
return cell
}