ios - 如何使用 Collection View 单元格的图像选择器

Question

我目前正在制作一个应用程序，要求用户使用图像选择器将图像加载到CollectionViewCell。我正在使用一个具有 UIImageView 的原型(prototype)单元格，但是每当我发布照片时，它只会转到第一个单元格，而不是我按下的各个单元格。我想知道如何以针对我点击的特定单元格的方式编写代码并相应地使用图像选择器。

func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return self.items.count
}
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {

    // get a reference to our storyboard cell
    let cell = collectionView.dequeueReusableCellWithReuseIdentifier(reuseIdentifier, forIndexPath: indexPath) as! MyCollectionViewCell

    cell.myLabel.text = self.items[indexPath.item]
    cell.tag = self.integer[indexPath.item]

    cell.backgroundColor = UIColor.yellowColor()

    cell.myAdd.addTarget(self, action: "importPicture:", forControlEvents: UIControlEvents.TouchUpInside)


    return cell
}

func importPicture(sender: UIButton) {
    imagePicker.delegate = self
    imagePicker.sourceType = .PhotoLibrary
    imagePicker.allowsEditing = true
    presentViewController(imagePicker, animated: true, completion: nil)
}

func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
    let
    cell = myCollection.cellForItemAtIndexPath(NSIndexPath(forRow: 0, inSection: 0)) as! MyCollectionViewCell
    var newImage: UIImage

    imagePicker.dismissViewControllerAnimated(true, completion: nil)
    let pickedImage1 = info[UIImagePickerControllerEditedImage] as? UIImage
        currentPickerTarget.image = pickedImage1
        currentPickerTarget = cell.myImages


    myCollection.reloadData()

}

// MARK: - UICollectionViewDelegate protocol

func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
    // handle tap events
    let cell = collectionView.dequeueReusableCellWithReuseIdentifier(reuseIdentifier, forIndexPath: indexPath) as! MyCollectionViewCell
    print("You selected cell #\(indexPath.item)!")
    print("\(indexPath.row)")
    cell.backgroundColor = UIColor.blueColor()
}

func numberOfSectionsInCollectionView(collectionView: UICollectionView) -> Int {
    // 1
    // Return the number of sections
    return 1
}

override func viewDidLoad() {
    super.viewDidLoad()

    let longPressGesture = UILongPressGestureRecognizer(target: self, action: "handleLongGesture:")
    self.myCollection.addGestureRecognizer(longPressGesture)
}

Answer 1

发生这种情况是因为您正在重写选取的图像并将其添加到数组的索引 0 中，我将删除行 cell.myAdd.addTarget(self, action: "importPicture:", forControlEvents: UIControlEvents.TouchUpInside)只需修改函数 func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
}保存您之前选择的单元格的indexpath.row，然后执行函数 importPicture ，当用户完成选择他的图片时，您将其与您之前保存的索引一起保存到图像数组中，如果您选择相同的单元格图像只会重写自己，新单元格会将新图像添加到数组中。