Any idea why this func is writing/updating the first cell in table and not the selected one in PFQueryTableViewController?

Question

In my app users can post to Parse backend and their posts are displayed in a timeline (PFQueryTableViewController). Each cell in this tableview has a button which the users can press to 'like' the post. Until yesterday I had the function to like sorted but suddenly today it is no longer working.

Now when a user likes a post it does a number of things: adds the user's objectId to an array in the post PFObject("likedBy"), and adds the post PFObject to a relation in the User class ("likedPosts").

But what seems to now be happening is it works but with the following problems:

it most often will like whatever post/cell is at the top of the tableview instead of the one the user actually clicks like on -- e.g. tap like button on the 4th post in the table and it will like the 1st post instead
it might like the intended post but then the user is unable to like anything else after that
or it may just not like anything at all

Here is the code I am using, where am I going wrong? It was working fine yesterday and I don't think it is a Parse backend problem because I set the app up to work with an entirely new backend an hour ago and the problem persists.

func likePost(sender: UIButton) {

        let hitPoint = sender.convertPoint(CGPointZero, toView:  self.tableView)
        let hitIndex = tableView.indexPathForRowAtPoint(hitPoint)
        let object = objectAtIndexPath(hitIndex)

        let userId = PFUser.currentUser()?.objectId

        let relayedResponses = (PFUser.currentUser()?.relationForKey("likedPosts"))! as PFRelation
        likedPosts.addObject(object!)
        PFUser.currentUser()?.saveInBackground()

        object?.addUniqueObject(userId!, forKey: "likedBy")
        object?.saveInBackground()

        self.tableView.reloadData()

}

And in my cellForRowAtIndexPath I have:

cell.likeButton.tag = indexPath.row
    cell.likeButton.addTarget(self, action: "likePost:", forControlEvents: UIControlEvents.TouchUpInside)

I will appreciate any help as this is DRIVING ME MAD!! I just can't see where the problem is!

score 0 · Accepted Answer · answered Dec 10 '15 at 16:43

0

You converting CGPointZero to tableView. Its is actually CGPoint(0,0) and always returns 0,0 which is first row of the table view.

answered Dec 10 '15 at 16:43

Juri Noga

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Thanks for that! Do you know how I would go about making certain that it only likes the post/row that I click and not the first row? – Chris Wright Dec 10 '15 at 17:02
Use button's `tag` like that `let index = sender.tag` and then `let object = objectAtIndexPath(index)` – Juri Noga Dec 10 '15 at 17:03
Ah this is making more sense now... But now I have an error in the objectAtIndexPath(index) line saying 'cannot convert value of type 'Int' to expected argument type 'NSIndexPath?' – Chris Wright Dec 10 '15 at 17:16
So change to that. `let index = NSIndexPath(forItem: sender.tag, inSection: 0)` – Juri Noga Dec 10 '15 at 17:18
Perfect! Oddly enough I tried the code I had before and it was working again, but I've now opted for your revisions as I know for definite they work and I now understand why they work. Thanks! – Chris Wright Dec 10 '15 at 17:33

Any idea why this func is writing/updating the first cell in table and not the selected one in PFQueryTableViewController?

1 Answers1