如何使用 UIcollectionView 制作 prepareForSegue

Question

我对这段代码有疑问：

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

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "showDetailsSegue" {
        let detailsVC: DetailsViewController = segue.destinationViewController as! DetailsViewController
        let indexPaths = self.collectionView.indexPathsForSelectedItems()
        let indexPath = indexPaths[0] as! NSIndexPath
         var thisCoupon = self.userCoupons[indexPath.row] as UserCoupons
         detailsVC.userCoupon = self.userCoupons[indexPath.row]
        detailsVC.pinArray = self.pinArray
        detailsVC.userStamp = self.userStamps[indexPath.row]

    }

}

当我在集合视图中只有一项时，我无法转到 DetailsViewController。当我的项目很少时，我的 segue 会处理没有最后一项的项目。

    func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return self.userCoupons.count
}

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
    var cell = collectionView.dequeueReusableCellWithReuseIdentifier("Cell", forIndexPath: indexPath) as! StampsCollectionViewCell

    let thisStamp = self.userCoupons[indexPath.row]

    if thisStamp.couponImage != nil {
        var image = thisStamp.couponImage
        cell.stampImage.image = image
    }

    var day: NSString = (thisStamp.couponDate as NSString).stringByReplacingCharactersInRange(NSRange(location: 0, length: 6), withString: "")
    var monthS: NSString = (thisStamp.couponDate as NSString).stringByReplacingCharactersInRange(NSRange(location: 0, length: 4), withString: "")
    var month:  NSString = monthS.stringByReplacingCharactersInRange(NSRange(location: 2, length: 2), withString: "")
    var year: NSString = (thisStamp.couponDate as NSString).stringByReplacingCharactersInRange(NSRange(location: 4, length: 4), withString: "")

    cell.stampDate.text = "\(day).\(month).\(year)"
    return cell
}

Answer 1

下面的代码应该很适合你：

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

    if segue.identifier == "showDetailsSegue" {

          let detailsVC = segue.destinationViewController as! DetailsViewController
          let cell = sender as! StampsCollectionViewCell
          let indexPaths = self.couponsCollectionView.indexPathForCell(cell)
          var thisCoupon = self.userCoupons[indexPaths!.row] as UserCoupons
          detailsVC.userCoupon = thisCoupon
          detailsVC.pinArray = self.pinArray
          detailsVC.userStamp = self.userStamps[indexPaths!.row]

    }

}

更新：请检查从服务器传入的数据是否正确，它可能会起作用！

Answer 2

你可以试试这个：

override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
    let cell = collectionView.cellForItemAtIndexPath(indexPath)
    self.performSegueWithIdentifier("showDetailsSegue", sender: cell)
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "showDetailsSegue" {
        let detailsVC: DetailsViewController = segue.destinationViewController as! DetailsViewController
        let cell = sender as! StampsCollectionViewCell
        let indexPath = self.collectionView!.indexPathForCell(cell)
        var thisCoupon = self.userCoupons[indexPath.row] as UserCoupons
        detailsVC.userCoupon = thisCoupon
        detailsVC.pinArray = self.pinArray
        detailsVC.userStamp = self.userStamps[indexPath.row]

    }

}

Answer 3

试试这个：

let cell = sender as StampsCollectionViewCell
let indexPath = self.collectionView!.indexPathForCell(cell)

您的代码将是：

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

{
    if segue.identifier == "showDetailsSegue" {
        let detailsVC: DetailsViewController = segue.destinationViewController as! DetailsViewController
        let cell = sender as StampsCollectionViewCell
        let indexPath = self.collectionView!.indexPathForCell(cell)
        var thisCoupon = self.userCoupons[indexPath.row] as UserCoupons
        detailsVC.userCoupon = thisCoupon
        detailsVC.pinArray = self.pinArray
        detailsVC.userStamp = self.userStamps[indexPath.row]

    }

}

希望它会起作用。