ios - UICollectionview 从库中加载照片。如何将图像传递到另一个 View Controller

Question

我有一个collectionview，它使用照片框架从照片库加载图像。我添加了一个名为saveSelected的segue，以便将所选图像传递给另一个 >viewController NoteDetailViewController.我怎样才能传递相同的

下面给出了我的 AddPhotoViewController

import UIKit
import Photos
private let reuseIdentifier = "PhotoCell"
class AddPhotoViewController: UIViewController , UIImagePickerControllerDelegate ,UINavigationControllerDelegate ,UICollectionViewDataSource ,UICollectionViewDelegate
{

@IBOutlet weak var photoAlbum: UICollectionView!

var TakenImage : UIImageView!

var assetCollection: PHAssetCollection!
var photosAsset: PHFetchResult!
var assetThumbnailSize: CGSize!
let imagePicker: UIImagePickerController! = UIImagePickerController()
var cameraon : Bool = false

override func viewDidLoad()
{
    super.viewDidLoad()

    let collection:PHFetchResult = PHAssetCollection.fetchAssetCollectionsWithType(.SmartAlbum, subtype: .SmartAlbumUserLibrary, options: nil)

    var i = 0
    repeat
    {
        if let first_Obj:AnyObject = collection.objectAtIndex(i)
        {
            self.assetCollection = first_Obj as! PHAssetCollection
        }
        i++
    }while( i < collection.count)



    // Do any additional setup after loading the view.
}

@IBAction func takePhoto(sender: AnyObject) {
    if (UIImagePickerController.isSourceTypeAvailable(.Camera)) {
        if UIImagePickerController.availableCaptureModesForCameraDevice(.Rear) != nil {
            imagePicker.allowsEditing = false
            imagePicker.sourceType = .Camera
            imagePicker.cameraCaptureMode = .Photo
            presentViewController(imagePicker, animated: true, completion: {})
            cameraon = true
        } else {
            print("Rear camera doesn't exist")
        }
    } else {
        print("Camera inaccessable")
    }

}
func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage!, editingInfo: [NSObject : AnyObject]!) {
    TakenImage.image  = image
    if (cameraon)
    {
        let imageData = UIImageJPEGRepresentation(TakenImage.image!, 0.6)
        let compressedJPGImage = UIImage(data: imageData!)
        UIImageWriteToSavedPhotosAlbum(compressedJPGImage!, nil, nil, nil)

    }
    self.dismissViewControllerAnimated(true, completion: nil)
}


func imagePickerControllerDidCancel(picker: UIImagePickerController) {
    print("User canceled image")
    dismissViewControllerAnimated(true, completion: {
        // Anything you want to happen when the user selects cancel
    })
}


override func viewWillAppear(animated: Bool)
{
    if let layout = self.photoAlbum!.collectionViewLayout as? UICollectionViewFlowLayout{
        let cellSize = layout.itemSize

        self.assetThumbnailSize = CGSizeMake(cellSize.width, cellSize.height)
    }

    //fetch the photos from collection
    self.photosAsset = PHAsset.fetchAssetsInAssetCollection(self.assetCollection, options: nil)

    self.photoAlbum!.reloadData()


}

// MARK: UICollectionViewDelegate

/*
// Uncomment this method to specify if the specified item should be selected
override func collectionView(collectionView: UICollectionView, shouldSelectItemAtIndexPath indexPath: NSIndexPath) -> Bool {
return true
}
*/


override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)
{
    if (segue.identifier == "savePhoto")
    {
        if let controller : NoteDetailViewController = segue.destinationViewController as? NoteDetailViewController
        {
            controller.imageView.image = TakenImage.image
        }
    }
/*    if (segue.identifier == "saveSelected")
    {
        if let controller2 : NoteDetailViewController = segue.destinationViewController as? NoteDetailViewController
        {
             if let cell = photoAlbum.cel as? PhotoAlbumCollectionViewCell
             {


            }
        }

    }*/
}


func numberOfSectionsInCollectionView(collectionView: UICollectionView) -> Int
{
    // #warning Incomplete implementation, return the number of sections
    return 1
}

func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
{
    // #warning Incomplete implementation, return the number of items
    var count: Int = 0

    if(self.photosAsset != nil){
        count = self.photosAsset.count
    }
    print("\(self.photosAsset.count)")
    return count
}
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell
{
    let cell: PhotoAlbumCollectionViewCell = photoAlbum.dequeueReusableCellWithReuseIdentifier("PhotoCell", forIndexPath: indexPath) as! PhotoAlbumCollectionViewCell

    //Modify the cell
    let asset: PHAsset = self.photosAsset[indexPath.item] as! PHAsset

    PHImageManager.defaultManager().requestImageForAsset(asset, targetSize: self.assetThumbnailSize, contentMode: .AspectFill, options: nil, resultHandler: {(result, info)in
        if let image = result {
            cell.setThumbnailImage(image)
        }
    })

    return cell
}


func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {



}
func collectionView(collectinView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAtIndex section: Int) -> CGFloat {
    return 4
}

func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAtIndex section: Int) -> CGFloat {
    return 1
}

func collectionView(collectionView: UICollectionView, shouldShowMenuForItemAtIndexPath indexPath: NSIndexPath) -> Bool {
    return false
}

func collectionView(collectionView: UICollectionView, canPerformAction action: Selector, forItemAtIndexPath indexPath: NSIndexPath, withSender sender: AnyObject?) -> Bool {
    return false
}

func collectionView(collectionView: UICollectionView, performAction action: Selector, forItemAtIndexPath indexPath: NSIndexPath, withSender sender: AnyObject?) {

    self.dismissViewControllerAnimated(false, completion: nil)

}

}

我应该如何修改didSelectItemAtIndexPath和prepareForSegue来实现这一点？

Answer 1

您已使用 CollectionViewCell 设置了 segue，因此无需在 didSelectItemAtIndexPath 方法中编写任何内容，请像这样更改代码prepareForSegue 方法

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if (segue.identifier == "saveSelected")
    {
        let cell = sender as! PhotoAlbumCollectionViewCell
        let indexPath = tableView.indexPathForCell(cell)
        let destVC = segue.destinationViewController as! NoteDetailViewController
        destVC.asset = self.photosAsset[indexPath.item] as! PHAsset
    }
}

现在在 NoteDetailViewController 中创建一个名为 asset 的全局对象，如下所示

var asset: PHAsset!

现在在 NoteDetailViewController 的 viewDidLoad 中添加如下代码

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.
    PHImageManager.defaultManager().requestImageForAsset(asset, targetSize: self.assetThumbnailSize, contentMode: .AspectFill, options: nil, resultHandler: {(result, info)in
        if let image = result {
            self.imageView.image = image
        }
    })
}

希望这对您有帮助。