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iOS

Posted by jean-marie castellucci
jean-marie castellucci
4,954 Points

Ribbit/swift clone : loading followed user post

Hello

I' m trying to make an instagram clone with swift, based on the Ribbit tuto. People can share photos and follow other users etc etc. I made a PFRelation between users using Parse. What i would like to do now, is to show in my WalltableViewController, only the followed users post.

I made a function to load all the post in a NSMutable array called timeLineData.

I ve even made a function to get the followed users ina NSMutable array called followedFriends..

But i don't succeed in filtering the loading post function with followedFriends. I have this error : Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Cannot do a comparison query for type: __NSArrayM'

Here is my code :

     import UIKit
     import QuartzCore

    class WallTableViewController: UITableViewController, UINavigationControllerDelegate {

   @IBOutlet var posterAvatar: UIImageView!

override func preferredStatusBarStyle() -> UIStatusBarStyle {
    return UIStatusBarStyle.LightContent
}


var timeLineData:NSMutableArray = NSMutableArray ()
var followedFriends:NSMutableArray = NSMutableArray ()

func loadUser () {

    followedFriends.removeAllObjects()
    var friendsRelation: AnyObject! = PFUser.currentUser().objectForKey("KfriendsRelation")


    var findUser : PFQuery = friendsRelation.query()


    findUser.findObjectsInBackgroundWithBlock { (objects:[AnyObject]!, error:NSError!) -> Void in
        if !(error != nil) {
            // The find succeeded.
            println("succesfull load Users")
            // Do something with the found objects
            for object  in objects  {
                self.followedFriends.addObject(object)
                println("users added to userlist")

                for item in self.followedFriends {
                    println(item)                    }
            }
            self.tableView.reloadData()
        } else {
            // Log details of the failure
            println("error loadind user ")

        }

    }
}


func loadPost () {

    timeLineData.removeAllObjects()

    let currentUser = PFUser.currentUser()

        var findPost:PFQuery = PFQuery(className: "UserPost")


    findPost.whereKey("from", equalTo: followedFriends )


        findPost.orderByDescending("createdAt")


        findPost.findObjectsInBackgroundWithBlock {
            (objects: [AnyObject]! , error: NSError!) -> Void in
            if !(error != nil) {
                // The find succeeded.
                println("current user post finded")
                // Do something with the found objects
                for object  in objects  {
                    self.timeLineData.addObject(object)
                }
                self.tableView.reloadData()
            } else {
                // Log details of the failure
                println("error loadind user post")
            }


        }

    }


override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    return 1
}

 override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return timeLineData.count
}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    let cell:WallTableViewCell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as WallTableViewCell

    let userPost:PFObject = self.timeLineData.objectAtIndex(indexPath.row) as PFObject

    //define the username

    var findUser:PFQuery = PFUser.query()
    findUser.whereKey("objectId", equalTo: userPost.objectForKey("from").objectId)

    findUser.findObjectsInBackgroundWithBlock{
        (objects:[AnyObject]!, error:NSError!) -> Void in

        if !(error != nil) {
            if let user:PFUser = (objects as NSArray).lastObject as? PFUser {
                cell.usernameLabel.text = user.username

                // define avatar poster

                if let avatarImage:PFFile = user["profileImage"] as? PFFile {
                    avatarImage.getDataInBackgroundWithBlock{(imageData:NSData!, error:NSError!)-> Void in

                        if !(error != nil) {

                            let image:UIImage = UIImage(data: imageData)


                            cell.posterAvatar.image = image as UIImage
                            cell.posterAvatar.layer.cornerRadius = 24
                            cell.posterAvatar.clipsToBounds = true

                        }

                    }
                }
                else {
                    cell.posterAvatar.image = UIImage(named: "Avatar-1")
                    cell.posterAvatar.layer.cornerRadius = 24
                    cell.posterAvatar.clipsToBounds = true
                }
            }

        }

    }

    //define the imagepost

    let imagesPost:PFFile = userPost["imageFile"] as PFFile


    imagesPost.getDataInBackgroundWithBlock{(imageData:NSData!, error:NSError!)-> Void in

        if !(error != nil) {

            let image:UIImage = UIImage(data: imageData)

            cell.imagePosted.image = image as UIImage


        }
        else {
            println("error")
        }
    }


    return cell
}


override func viewDidAppear(animated: Bool) {
    var currentUser = PFUser.currentUser()
    if (currentUser != nil) {
        println("User allready logued")
    }

    else {
        // Show the signup or login screen

        self.performSegueWithIdentifier("goToLogIn", sender: self)
    }

}


override func viewWillAppear(animated: Bool) {
    self.tableView.separatorColor = UIColor.whiteColor()

    tabBarController?.tabBar.tintColor = UIColor.whiteColor()
    self.loadUser()
    self.loadPost()
    self.tableView.reloadData()

}

}

2 Answers

Stone Preston
Stone Preston
42,016 Points

you cant pass in an array as a key to compare to. you may be able to use another query method though with an array.

one thing you could do is you could use a query to first get the users friends, then use the results of that query to find all of the posts of those users:

//query for the friends of the user
var friendsRelation: AnyObject! = PFUser.currentUser().objectForKey("KfriendsRelation")
var findFriends : PFQuery = friendsRelation.query()

//using the friends from the query above, we find all the posts of the friends of the current user
var findPosts:PFQuery = PFQuery(className: "UserPost")
findPosts.whereKey("from", matchesQuery:findFriends)
findPost.orderByDescending("createdAt")

//run the query
 findPosts.findObjectsInBackgroundWithBlock { (objects:[AnyObject]!, error:NSError!) -> Void in
        if !(error != nil) {
            //found posts

            self.tableView.reloadData()
        } else {
            // Log details of the failure
            println("error loadind posts ")

        }

    }

the above basically combines finding the users friends, and then getting the users post into one simply query.

jean-marie castellucci
jean-marie castellucci
4,954 Points
jean-marie castellucci
jean-marie castellucci
4,954 Points

Thank you Stone it work perfectly ! You saved my life another time...;)