从collectionView到Detail

Question

我将数据从一个CollectionViewController传递到详细信息ViewController。一切似乎都在起作用，但是"prepareForSegue发生在"didSelectItemAtIndexPath"之前，所以它传递的是我最后一次选择的项目的数据而不是我现在正在选择的项目。

这是我对collectionViewController的错误代码

var cellSelected : Int = 0

override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
    cellSelected = indexPath.row
    println("Did select!")
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {

    if segue.identifier == "identifierName" {
        var secondScene = segue.destinationViewController as detailVC

        secondScene.authorDetail = data[cellSelected].userOfImg
        secondScene.likesDetail = data[cellSelected].likesInImg
        secondScene.imageDetail = data[cellSelected].imgPath
        println("Prepare for segue")
    }
}

调试区域的结果是：

1. 准备segue
2. 选择了！

Answer 1

我找到了解决方法。要使用shouldSelectItemAtIndexPath代替didSelectItemAtIndexPath。执行此操作shouldSelectItemAtIndexPath将在prepareForSegue之前执行，并将解决发送您正在选择的项目的数据的问题，而不是上次选择的项目。

Answer 2

正确的解决方案

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "identifierName" {
        var secondScene = segue.destinationViewController as detailVC
        let cell = sender as UICollectionViewCell
        let indexPath = collectionView.indexPathForCell(cell)
        secondScene.authorDetail = data[indexPath.row].userOfImg
        secondScene.likesDetail = data[indexPath.row].likesInImg
        secondScene.imageDetail = data[indexPath.row].imgPath
        println("Prepare for segue")
    }
}