Refactoring the ImagePicker.

Demo/ImagePickerDemo/ImagePickerDemo/AppDelegate.swift

@@ -4,15 +4,8 @@ import ImagePicker
 @UIApplicationMain
 class AppDelegate: UIResponder, UIApplicationDelegate {
 
-  lazy var imagePickerController: ImagePickerController = {
-    let imagePickerController = ImagePickerController()
-    return imagePickerController
-    }()
-
-  lazy var window: UIWindow? = {
-    let window = UIWindow(frame: UIScreen.mainScreen().bounds)
-    return window
-    }()
+  lazy var imagePickerController: ImagePickerController = ImagePickerController()
+  lazy var window: UIWindow? = UIWindow(frame: UIScreen.mainScreen().bounds)
 
   func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
     window?.rootViewController = imagePickerController

Source/BottomView/ImageStack.swift

@@ -22,8 +22,8 @@ public class ImageStack {
     NSNotificationCenter.defaultCenter().postNotificationName(Notifications.imageDidDrop, object: self, userInfo: ["image" : asset])
   }
 
-  public func resetAssets(assets: [PHAsset]) {
-    self.assets = assets
+  public func resetAssets(assetsArray: [PHAsset]) {
+    assets = assetsArray
     NSNotificationCenter.defaultCenter().postNotificationName(Notifications.stackDidReload, object: self, userInfo: nil)
   }
 

Source/CameraView/CameraView.swift

@@ -143,9 +143,7 @@ class CameraView: UIViewController {
 
     captureDevice = capturedDevices?.firstObject as? AVCaptureDevice
 
-    if captureDevice != nil {
-      beginSession()
-    }
+    if captureDevice != nil { beginSession() }
   }
 
   // MARK: - Actions
@@ -190,7 +188,12 @@ class CameraView: UIViewController {
           ? AVCaptureSessionPreset1280x720
           : AVCaptureSessionPreset640x480
 
-        try! self.captureSession.addInput(AVCaptureDeviceInput(device: self.captureDevice))
+        do { try
+          self.captureSession.addInput(AVCaptureDeviceInput(device: self.captureDevice))
+        } catch {
+          print("There was an error capturing your device.")
+        }
+
         self.captureSession.commitConfiguration()
         UIView.animateWithDuration(0.7, animations: { [unowned self] in
           self.containerView.alpha = 0
@@ -199,21 +202,20 @@ class CameraView: UIViewController {
   }
 
   func flashCamera(title: String) {
+    guard let _ = captureDevice?.hasFlash else { return }
+
+    do {
+      try captureDevice?.lockForConfiguration()
+    } catch _ { }
+
+    switch title {
+    case "ON":
+      captureDevice?.flashMode = .On
+    case "OFF":
+      captureDevice?.flashMode = .Off
+    default:
+      captureDevice?.flashMode = .Auto
 
-    if (captureDevice?.hasFlash != nil) {
-      do {
-        try captureDevice?.lockForConfiguration()
-      } catch _ {
-      }
-      switch title {
-      case "ON":
-        captureDevice?.flashMode = .On
-      case "OFF":
-        captureDevice?.flashMode = .Off
-      default:
-        captureDevice?.flashMode = .Auto
-
-      }
     }
   }
 

Source/ImagePickerController.swift

@@ -60,11 +60,10 @@ public class ImagePickerController: UIViewController {
 
   public weak var delegate: ImagePickerDelegate?
   public var stack = ImageStack()
-  let totalHeight = UIScreen.mainScreen().bounds.size.height
-  let totalWidth = UIScreen.mainScreen().bounds.size.width
-  var initialFrame: CGRect!
-  var initialContentOffset: CGPoint!
-  var numberOfCells: Int!
+  let totalSize = UIScreen.mainScreen().bounds.size
+  var initialFrame: CGRect?
+  var initialContentOffset: CGPoint?
+  var numberOfCells: Int?
   var statusBarHidden = true
 
   public var doneButtonTitle: String? {
@@ -106,8 +105,8 @@ public class ImagePickerController: UIViewController {
     let galleryHeight: CGFloat = UIScreen.mainScreen().nativeBounds.height == 960
       ? ImageGalleryView.Dimensions.galleryBarHeight : GestureConstants.minimumHeight
 
-    galleryView.frame = CGRectMake(0, totalHeight - bottomContainer.frame.height - galleryHeight,
-      totalWidth, galleryHeight)
+    galleryView.frame = CGRectMake(0, totalSize.height - bottomContainer.frame.height - galleryHeight,
+      totalSize.width, galleryHeight)
     galleryView.updateFrames()
     galleryView.checkStatus()
 
@@ -192,7 +191,7 @@ public class ImagePickerController: UIViewController {
   }
 
   func updateGalleryViewFrames(constant: CGFloat) {
-    galleryView.frame.origin.y = totalHeight - bottomContainer.frame.height - constant
+    galleryView.frame.origin.y = totalSize.height - bottomContainer.frame.height - constant
     galleryView.frame.size.height = constant
   }
 
@@ -306,7 +305,7 @@ extension ImagePickerController: ImageGalleryPanGestureDelegate {
 
     initialFrame = galleryView.frame
     initialContentOffset = galleryView.collectionView.contentOffset
-    numberOfCells = Int(initialContentOffset.x / collectionSize.width)
+    if let contentOffset = initialContentOffset { numberOfCells = Int(contentOffset.x / collectionSize.width) }
   }
 
   func panGestureRecognizerHandler(gesture: UIPanGestureRecognizer) {
@@ -323,6 +322,8 @@ extension ImagePickerController: ImageGalleryPanGestureDelegate {
   }
 
   func panGestureDidChange(translation: CGPoint) {
+    guard let initialFrame = initialFrame else { return }
+
     let galleryHeight = initialFrame.height - translation.y
 
     if galleryHeight >= GestureConstants.maximumHeight { return }
@@ -350,6 +351,8 @@ extension ImagePickerController: ImageGalleryPanGestureDelegate {
   }
 
   func panGestureDidEnd(translation: CGPoint, velocity: CGPoint) {
+    guard let initialFrame = initialFrame else { return }
+
     let galleryHeight = initialFrame.height - translation.y
 
     if galleryView.frame.height < GestureConstants.minimumHeight && velocity.y < 0 {