如何使用IOS中的“照片”框架在相册中添加图像阵列？

Question

I'm trying to integrate DKImagePicker into my app, because it simply looks better. When the user selects an album I want the app to save the images the user chose, in a new folder that I've created. Here is how I'm attempting to handle the save:

...

@IBAction func openAlbum(sender: AnyObject) {

  // pickerController is  DKImagePickerController 

  pickerController.didSelectAssets = { [unowned self] (asset: [DKAsset]) in
    print("didSelectAssets")
    self.transferSelectedAssetsToAlbum(asset)
  }
  self.presentViewController(pickerController, animated: true, completion: nil)
}

func transferSelectedAssetsToAlbum(assets: [DKAsset]) {
  PHPhotoLibrary.sharedPhotoLibrary().performChanges({

  // Here I want to save all items in assets in the album
  for asset in assets {
    let createAssetRequest = PHAssetChangeRequest.creationRequestForAssetFromImage(asset.fullScreenImage!)
    let assetPlaceholder = createAssetRequest.placeholderForCreatedAsset
    let albumChangeRequest = PHAssetCollectionChangeRequest(forAssetCollection: self.assetCollection)
    albumChangeRequest?.addAssets([assetPlaceholder])
  }

  }, completionHandler: {
    success, error in
    print(success)
    print(error)
  })
} 

...

When running this Xcode, it complains saying 'NSFastEnumeration' cannot be used with array litteral . I understand this is because of albumChangeRequest?.addAssets([assetPlaholder]) should not be under for .. in loop. But, I want to save every image in the assets? How can I make it work without a for loop?

Hopefully, I made that clear enough. If not please let me know so I can clarify my question.

Answer 1

Apparently the error is misleading. All that was missing to make this work is ! for assetPlaceholder . So all I did was replace albumChangeRequest?.addAssets([assetPlaceholder]) with albumChangeRequest?.addAssets([assetPlaceholder!])