ios - UICollectionView prepareForSegue indexPathForCell 为零 iOS 9

Question

问题是这一行返回零:

if let indexPath = self.collectionView?.indexPathForCell(sender as! UICollectionViewCell) 

因此我无法传递任何信息，标识符已设置且委托(delegate)已设置。

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "DetalleSegueIdentifier" {
        if let indexPath = self.collectionView?.indexPathForCell(sender as! UICollectionViewCell) {
            let detailVC = segue.destinationViewController as! DetalleNoticiaViewController
            detailVC.contact = self.noticia[indexPath.row]
        }
    }
}

func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
    self.performSegueWithIdentifier("DetalleSegueIdentifier", sender: collectionView.cellForItemAtIndexPath(indexPath))
}

有什么帮助吗？

Answer 1

问题是如何尝试取回单元格。您必须在 performSegueWithIdentifier 中传递单元格，然后在 prepareForSegue 中恢复它。这是代码:

func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
    self.performSegueWithIdentifier("DetalleSegueIdentifier", sender: collectionView.cellForItemAtIndexPath(indexPath))
}

然后

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "DetalleSegueIdentifier" {
        if let cell = sender as? UICollectionViewCell{
            let indexPath = self.collectionView!.indexPathForCell(cell)
            let detailVC = segue.destinationViewController as! DetalleNoticiaViewController
            detailVC.contact = self.noticia[indexPath.row]

        }

    }
}

希望对您有所帮助!