Sending Cell data to destinationViewController with prepareForSegue - ios

Question

I have added a UILongPressGestureRecognizer to my UICollectionViewCell and created a segue, so by long pressing a cell the user segues to a ViewController.
I already have an ordinary segue using the didSelect method to display cell details, but the secondary long press gesture segue takes the user to a action screen to delete the cell.
Unfortunately when using the prepareForSegue to send the cell data to the destinationViewController I cannot use the standard let indexPaths = self.collectionView.indexPathForSelectedRow() method because I am creating my own selection when using a gesture recogniser.
So how can I send the cell data to the destinationViewController with prepareForSegue using the gestureRecognizer ?
if segue.identifier == "cellAction" {
let vc = segue.destinationViewController as! CellActionViewController
//This will cause an 'array index out of range error
let indexPaths = self.collectionView.indexPathsForSelectedItems()
let indexPath = indexPaths[0] as! NSIndexPath
//Here is how I would send the cell data
let selectedCell = Items[indexPath.row]
vc.selectedItem = selectedCell
}

Answer 1

So you need to access the particular cell that was pressed, and use this information to obtain its index path from within prepareForSegue(_:sender:).
The first thing to note is that sender parameter on the prepareForSegue method. I presume you are calling performSegueWithIdentifier(_:sender:) from your gesture handling function. Notice this also has a sender parameter, which is the same object that is passed to prepareForSegue. You can use this to pass your cell instance.
The second thing to note is that UIGestureRecognizer has a view property, which should most likely be the cell itself. Armed with this knowledge, you can pass the pressed cell instance to prepareForSegue:
func handleLongPress(longPress: UILongPressGestureRecognizer) {
if longPress.state == .Ended {
performSegueWithIdentifier("cellAction", sender: longPress.view)
}
}
Now, within prepareForSegue you can cast sender to your cell class, and get its index path using UICollectionViews indexPathForCell(_:) method:
override prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "cellAction" {
let vc = segue.destinationViewController as! CellActionViewController
if let cell = sender as? MyCell {
let indexPath = collectionView.indexPathForCell(cell)
let selectedItem = items[indexPath.row]
vc.selectedItem = selectedItem
} else {
fatalError("Invalid sender, was expecting instance of MyCell.)
}
}
}