Long-Running Operation is being executed on main thread

Question

I've seen this question posted a few times but still haven't found a solution. I'm using a parse hosted sdk @ back4app.com

Receiving this error :

Warning: A long-running operation is being executed on the main thread. Break on warnBlockingOperationOnMainThread() to debug.

In my home.swift file the code is :

func queryPosts(text:String) {
    showHUD()

    let query = PFQuery(className: POSTS_CLASS_NAME)

    if text != "" {
        let keywords = text.componentsSeparatedByString(" ") as [String]
        query.whereKey(POSTS_QUOTE, containsString: "\(keywords[0])")
    }

    query.orderByDescending("createdAt")
    query.findObjectsInBackgroundWithBlock { (objects: [PFObject]?, error:NSError?)-> Void in
        if error == nil {
            self.postsArray = objects!
            self.postsTableView.reloadData()
            self.hideHUD()

        } else {
            self.simpleAlert("\(error!.localizedDescription)")
            self.hideHUD()
    }}
}

-

The data loads, and the app doesn't crash but the error is driving me nuts. I also realised there is a slight lag when I'm scrolling sometimes even for a second or two. If anyone can help that'll be great, thanks.

Answer 1

As per our discussion you can change your method with the given methods :

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCellWithIdentifier("PostCell", forIndexPath: indexPath) as! PostCell

    // Resize quote label
    cell.quoteView.frame = CGRectMake(30, 30, view.frame.size.width - 30*2, view.frame.size.width - 30*2)


    let postRecord = postsArray[indexPath.row]

    // Get User Pointer
    let userPointer = postRecord[POSTS_USER_POINTER] as! PFUser

    userPointer.fetchIfNeededInBackgroundWithBlock { (result, error) -> Void in
        cell.avatarImage.image = UIImage(named: "logo")
        let imageFile = userPointer[USER_AVATAR] as? PFFile
        imageFile?.getDataInBackgroundWithBlock({ (imageData, error) -> Void in
            if error == nil {
                if let imageData = imageData {
                    cell.avatarImage.image = UIImage(data:imageData)
                }}})
        cell.avatarImage.layer.cornerRadius = cell.avatarImage.bounds.size.width/2


        cell.usernameLabel.text = "\(userPointer[USER_FULLNAME]!)"


        cell.quoteLabel.text = "\(postRecord[POSTS_QUOTE]!)"
        let quoteColor = postRecord[POSTS_COLOR] as! Int
        cell.backgroundColor = colors[quoteColor]
        cell.quoteView.backgroundColor = colors[quoteColor]
    }


    // Assign tags to buttons in the cell
    cell.likeOutlet.tag = indexPath.row
    cell.reportOutlet.tag = indexPath.row
    cell.shareOutlet.tag = indexPath.row
    cell.avatarOutlet.tag = indexPath.row
    cell.commentOutlet.tag = indexPath.row

    return cell
    }