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iOS

Posted by Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points

IndexPath for collectionView

how do I get the index path for a collectionView?

similar to this var indexPath : NSIndexPath = self.tableView.indexPathForSelectedRow!

4 Answers

Steven Deutsch
Steven Deutsch
21,046 Points

Hey Mohamed Ibrahim,

indexPathForCell(cell: _ ) is a method that takes a cell as its argument. This means to retrieve the indexPath, you need to pass in the cell that you want this indexPath for. A use case for this would be when you are doing a segue from a collection view cell to another view controller.

In prepare for segue, there is a sender argument that is passed in when it is called. This is the object that triggered the segue, or in this case, lets say your collection view cell.

What you can do is typecast the sender as a UICollectionViewCell, so that you can use the indexPathForCell() method on it.

if let sender = sender as? UICollectionViewCell {
    let indexPath = self.collectionView.indexPathForCell(sender)
   // Whatever else you want to do
}

Good Luck

Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points

I figured it out thanks :)

Steven Deutsch
Steven Deutsch
21,046 Points
Steven Deutsch
Steven Deutsch
21,046 Points

Hey Mohamed Ibrahim,

You can use the indexPathForCell() method of UICollectionView. It takes a UICollectionViewCell as its argument.

Good Luck

Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points
Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points

this is what I tried var indexPath : NSIndexPath = self.collectionView.indexPathforCell! But it doesn't work :p I know I'm such a beginner buying you can type it out it would be nice. Thanks anyways

Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points

But if *

Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points
Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) { if let sender = InventionsCollectionViewCell() as? UICollectionViewCell{ let indexPath = inventionCollectionView.indexPathForCell(sender)

        if segue.identifier == "showInvention" {
            let destViewController = segue.destinationViewController as! inventionsDetailViewController

            destViewController.list = inventionsList(index: indexPath!.item)
        }
    }

}

is this correct?

Mohamed Ibrahim
Mohamed Ibrahim
1,086 Points

its says that indexPath is nil, and that it is bad instruction