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iOS

Posted by Tom Coomer
Tom Coomer
1,331 Points

Scroll UICollectionView to bottom

I would like to scroll the UICollectionView to the bottom so the last item is in the view. I have tried to use scrollToItemAtIndexPath but it does not seem to be working. I want this to happen after I have completed a query with Parse.com

Thanks

        var query = PFQuery(className:"Chat")
        //        query.whereKey("user", equalTo:currentUser)
        query.whereKey("rideId", equalTo:currentObjectId)
        query.orderByDescending("createdAt")
        query.includeKey("user")

        query.findObjectsInBackgroundWithBlock {
            (objects: [AnyObject]!, error: NSError!) -> Void in
            if error == nil {
                // The find succeeded.
                NSLog("Successfully retrieved \(objects.count) scores.")
                // Do something with the found objects
                for object in objects {
                    NSLog("%@", object.objectId)

                    var testId = object.objectId

                    println(testId)

                    self.orderedIdArray.append(testId)

                    var message = object.objectForKey("message") as String
                    self.messageString = message
                    self.messageArray.append(self.messageString)
                    println(message)

                    var nameId = object.objectForKey("user") as PFUser
                    var username = nameId.username as String
                    self.nameString = username
                    self.namesArray.append(self.nameString)

                    println("username: \(username)")

                    self.collectionView?.reloadData()
                }

            } else {
                // Log details of the failure
                NSLog("Error: %@ %@", error, error.userInfo!)
            }
                        NSLog("Ordered: %@", self.orderedIdArray)    
        }

1 Answer

Tom Coomer
Tom Coomer
1,331 Points

I have added this to run once the query has completed.

var item = self.collectionView(self.collectionView!, numberOfItemsInSection: 0) - 1
            var lastItemIndex = NSIndexPath(forItem: item, inSection: 0)
            self.collectionView?.scrollToItemAtIndexPath(lastItemIndex, atScrollPosition: UICollectionViewScrollPosition.Top, animated: false)
Stephen Whitfield
Stephen Whitfield
16,771 Points

So have you found a solution to your problem?

Tom Coomer
Tom Coomer
1,331 Points

Yes thank you.

Tom Coomer
Tom Coomer
1,331 Points

Yes thank you.