A block-based asset picker for videos, photos and files

AssetPicker.swift

import Photos
import MobileCoreServices

class AssetPicker: NSObject, UIImagePickerControllerDelegate, UINavigationControllerDelegate, UIDocumentPickerDelegate, UIDocumentMenuDelegate {

  static let sharedInstance = AssetPicker()

  private lazy var cameraPicker: UIImagePickerController = {
    let cameraPicker = UIImagePickerController()
    cameraPicker.delegate = self
    cameraPicker.sourceType = .Camera
    cameraPicker.allowsEditing = true
    return cameraPicker
  }()

  private lazy var videoCameraPicker: UIImagePickerController = {
    let cameraPicker = UIImagePickerController()
    cameraPicker.delegate = self
    cameraPicker.sourceType = .Camera
    cameraPicker.allowsEditing = true
    cameraPicker.mediaTypes = [String(kUTTypeMovie)]
    return cameraPicker
  }()

  private lazy var singlePhotoPicker: UIImagePickerController = {
    let imagePicker = UIImagePickerController()
    imagePicker.sourceType = .PhotoLibrary
    imagePicker.delegate = self
    imagePicker.allowsEditing = true
    return imagePicker
  }()

  private lazy var singleVideoPicker: UIImagePickerController = {
    let videoPicker = UIImagePickerController()
    videoPicker.sourceType = .PhotoLibrary
    videoPicker.delegate = self
    videoPicker.allowsEditing = true
    videoPicker.mediaTypes = [String(kUTTypeMovie)]
    return videoPicker
  }()

  private func takePhotoAction(vc: UIViewController) -> UIAlertAction {
    return UIAlertAction(title: "Take a photo", style: .Default) { _ in
      vc.presentViewController(self.cameraPicker, animated: true, completion: nil)
    }
  }

  private func chooseSinglePhotoFromLibraryAction(vc: UIViewController) -> UIAlertAction {
    return UIAlertAction(title: "Choose from library", style: .Default) { _ in
      vc.presentViewController(self.singlePhotoPicker, animated: true, completion: nil)
    }
  }

  private func takeVideoAction(vc: UIViewController) -> UIAlertAction {
    return UIAlertAction(title: "Take a video", style: .Default) { _ in
      vc.presentViewController(self.videoCameraPicker, animated: true, completion: nil)
    }
  }

  private func chooseSingleVideoFromLibraryAction(vc: UIViewController) -> UIAlertAction {
    return UIAlertAction(title: "Choose from library", style: .Default) { _ in
      vc.presentViewController(self.singleVideoPicker, animated: true, completion: nil)
    }
  }

  private let cancelAction = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil)

  private var pickSinglePhotoCompletionHandler: (UIImage? -> Void)?
  private var pickSingleVideoCompletionHandler: (NSURL? -> Void)?
  private var pickFileCompletionHandler: (NSURL? -> Void)?

  private var viewController: UIViewController?

  func pickPhoto(inViewController vc: UIViewController, sourceView: UIView? = nil, buttonItem: UIBarButtonItem? = nil, completionHandler: UIImage? -> Void) {
    self.pickSinglePhotoCompletionHandler = completionHandler
    let alert = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
    if UIImagePickerController.isSourceTypeAvailable(.Camera) {
      alert.addAction(takePhotoAction(vc))
    }
    alert.addAction(chooseSinglePhotoFromLibraryAction(vc))
    alert.addAction(cancelAction)
    
    if UIDevice.currentDevice().userInterfaceIdiom == .Pad {
      assert(sourceView != nil || buttonItem != nil,
        "You must provide either sourceView or buttonItem to \(__FUNCTION__) when on an iPad")
      alert.popoverPresentationController?.sourceView = sourceView
      alert.popoverPresentationController?.barButtonItem = buttonItem
      if let sourceView = sourceView {
        alert.popoverPresentationController?.sourceRect = sourceView.bounds
      }
    }
    
    vc.presentViewController(alert, animated: true, completion: nil)
  }

  func pickVideo(inViewController vc: UIViewController, sourceView: UIView? = nil, buttonItem: UIBarButtonItem? = nil, completionHandler: NSURL? -> Void) {
    self.pickSingleVideoCompletionHandler = completionHandler
    let alert = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
    if UIImagePickerController.isSourceTypeAvailable(.Camera) {
      alert.addAction(takeVideoAction(vc))
    }
    alert.addAction(chooseSingleVideoFromLibraryAction(vc))
    alert.addAction(cancelAction)
    
    if UIDevice.currentDevice().userInterfaceIdiom == .Pad {
      assert(sourceView != nil || buttonItem != nil,
        "You must provide either sourceView or buttonItem to \(__FUNCTION__) when on an iPad")
      alert.popoverPresentationController?.sourceView = sourceView
      alert.popoverPresentationController?.barButtonItem = buttonItem
      if let sourceView = sourceView {
        alert.popoverPresentationController?.sourceRect = sourceView.bounds
      }
    }
    
    vc.presentViewController(alert, animated: true, completion: nil)
  }

  func pickFile(inViewController vc: UIViewController, completionHandler: NSURL? -> Void) {
    self.viewController = vc
    self.pickFileCompletionHandler = completionHandler
    let documentMenuVC = UIDocumentMenuViewController(documentTypes: [String(kUTTypeContent)], inMode: .Import)
    documentMenuVC.delegate = self
    vc.presentViewController(documentMenuVC, animated: true, completion: nil)
  }

  //MARK: UIImagePickerControllerDelegate

  func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
    let mediaType = info[UIImagePickerControllerMediaType] as! NSString
    if mediaType == kUTTypeMovie {
      let videoURL = info[UIImagePickerControllerMediaURL] as! NSURL
      pickSingleVideoCompletionHandler?(videoURL)
    } else {
      let editedImage: UIImage? = info[UIImagePickerControllerEditedImage] as? UIImage
      let originalImage: UIImage = info[UIImagePickerControllerOriginalImage] as! UIImage
      let image = editedImage ?? originalImage
      pickSinglePhotoCompletionHandler?(image)
    }
    picker.presentingViewController?.dismissViewControllerAnimated(true, completion: nil)
  }

  func imagePickerControllerDidCancel(picker: UIImagePickerController) {
    pickSinglePhotoCompletionHandler?(nil)
    picker.presentingViewController?.dismissViewControllerAnimated(true, completion: nil)
  }


  // MARK: UIDocumentPickerMenu

  func documentMenu(documentMenu: UIDocumentMenuViewController, didPickDocumentPicker documentPicker: UIDocumentPickerViewController) {
    documentPicker.delegate = self
    viewController?.presentViewController(documentPicker, animated: true, completion: nil)
  }

  func documentMenuWasCancelled(documentMenu: UIDocumentMenuViewController) {
    pickFileCompletionHandler?(nil)
  }

  // MARK: UIDocumentPickerDelegate

  func documentPicker(controller: UIDocumentPickerViewController, didPickDocumentAtURL url: NSURL) {
    pickFileCompletionHandler?(url)
  }

  func documentPickerWasCancelled(controller: UIDocumentPickerViewController) {
    pickFileCompletionHandler?(nil)
  }

}

Basic usage

AssetPicker.sharedInstance.pickPhoto(inViewController: self) { image in
  if let image = image {
    // user did pick an image
  } else {
    // user did cancel
  }
}