How to have a nest queries in Parse in Swift

Question

I'm facing an issue with Parse.

I have three classes : Users, Posts, Likes

I'm using pointers for the Likes class User pointing to Users Class, and Post pointing to Posts class.

I'm retrieving all the posts and then I would like to see if the current user likes a post or not, and for that I'm nesting a query. the problem I have is that the posts are not updated with the like boolean value. I'm using that code :

func loaddata(limit:Int, skip:Int) {
    MainFunctions.getphones{(phones) -> Void in
        var indxesPath:[NSIndexPath] = [NSIndexPath]()
        let query = PFQuery(className: "Feed")
        query.whereKey("username", containedIn: phones)
        query.limit = limit
        query.skip = skip
        query.includeKey("from")
        query.addDescendingOrder("createdAt")
        query.findObjectsInBackgroundWithBlock {
            (objects: [PFObject]?, error: NSError?) -> Void in

        if error == nil {
            if let objects = objects {
                if objects.isEmpty {

                }
                else {

                    for object in objects {
                        let Date = object.createdAt
                        let post = Post(time: Date!)
                        let Type = object.objectForKey("type") as? String
                        post.Post = object
                        post.Post_message = object.objectForKey("Text") as? String
                        post.comments = object.objectForKey("commentaires") as? Int
                        post.likes = object.objectForKey("likes") as? Int

                        // See if the current user likes a post 

                        let query_like = PFQuery(className:"Likes")
                        query_like.whereKey("Post", equalTo: object)
                        query_like.whereKey("User", equalTo: PFUser.currentUser()!)
                        query_like.getFirstObjectInBackgroundWithBlock{
                            (like: PFObject?, error: NSError?) -> Void in
                            if error == nil && like != nil {
                                post.DoILike = true
                            } else {
                                post.DoILike = false
                            }
                        }

                        self.posts.append(post)
                        indxesPath.append(NSIndexPath(forRow: self.posts.count - 1, inSection: 0))


                    }

                    self.tableView.beginUpdates()
                    self.tableView.insertRowsAtIndexPaths(indxesPath, withRowAnimation:  UITableViewRowAnimation.Bottom)
                    self.tableView.endUpdates()
                    self.tableView.finishInfiniteScroll()
                    self.refreshControl.endRefreshing()
                }

            }

        } else {
            self.tableView.finishInfiniteScroll()
            self.refreshControl.endRefreshing()

        }
    }

}



}

Answer 1

query_like.getFirstObjectInBackgroundWithBlock is asynchrone so when you are adding the post to the posts array self.posts.append(post) post.DoILike will get it's default value. So make sure when appending post to posts you have already get if the user liked the post or not.