Merge pull request #14 from superpeteblaze/psmith/Swift4

Psmith/swift4

.swift-version

@@ -0,0 +1 @@
+4.0

.travis.yml

@@ -3,12 +3,12 @@
 # * https://github.com/supermarin/xcpretty#usage
 
 language: objective-c
-osx_image: xcode8
+osx_image: xcode9
 # cache: cocoapods
 # podfile: Example/Podfile
 before_install:
 - gem install cocoapods # Since Travis is not always on latest version
 # - pod install --project-directory=Example
 script:
-- set -o pipefail && xcodebuild -workspace Example/ScalingCarousel.xcworkspace -scheme ScalingCarousel-Example -sdk iphonesimulator -destination 'platform=iOS Simulator,OS=10.0,name=iPhone 7' ONLY_ACTIVE_ARCH=NO | xcpretty
+- set -o pipefail && xcodebuild -workspace Example/ScalingCarousel.xcworkspace -scheme ScalingCarousel-Example -sdk iphonesimulator -destination 'platform=iOS Simulator,OS=11.0,name=iPhone 7' ONLY_ACTIVE_ARCH=NO | xcpretty
 - pod lib lint

Example/Pods/Pods.xcodeproj/project.pbxproj

@@ -317,7 +317,15 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0730;
-				LastUpgradeCheck = 0700;
+				LastUpgradeCheck = 0900;
+				TargetAttributes = {
+					479882F85D2E213BDCC80F17AAAA8A63 = {
+						LastSwiftMigration = "";
+					};
+					E9582E7E712D7CD7A32DF86E8120CBC5 = {
+						LastSwiftMigration = 0900;
+					};
+				};
 			};
 			buildConfigurationList = 2D8E8EC45A3A1A1D94AE762CB5028504 /* Build configuration list for PBXProject "Pods" */;
 			compatibilityVersion = "Xcode 3.2";
@@ -382,6 +390,7 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 2CAFE40C0C16F348A480291448686E57 /* Pods-ScalingCarousel_Example.release.xcconfig */;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "";
 				"CODE_SIGN_IDENTITY[sdk=watchos*]" = "";
@@ -407,6 +416,8 @@
 				PRODUCT_NAME = Pods_ScalingCarousel_Example;
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -473,7 +484,8 @@
 				PRODUCT_NAME = ScalingCarousel;
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -489,19 +501,29 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				CODE_SIGNING_REQUIRED = NO;
 				COPY_PHASE_STRIP = YES;
 				ENABLE_NS_ASSERTIONS = NO;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
+				GCC_NO_COMMON_BLOCKS = YES;
 				GCC_PREPROCESSOR_DEFINITIONS = (
 					"POD_CONFIGURATION_RELEASE=1",
 					"$(inherited)",
@@ -515,6 +537,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				PROVISIONING_PROFILE_SPECIFIER = NO_SIGNING/;
 				STRIP_INSTALLED_PRODUCT = NO;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				SYMROOT = "${SRCROOT}/../build";
 				VALIDATE_PRODUCT = YES;
 			};
@@ -529,20 +552,30 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				CODE_SIGNING_REQUIRED = NO;
 				COPY_PHASE_STRIP = NO;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				ENABLE_TESTABILITY = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_DYNAMIC_NO_PIC = NO;
+				GCC_NO_COMMON_BLOCKS = YES;
 				GCC_OPTIMIZATION_LEVEL = 0;
 				GCC_PREPROCESSOR_DEFINITIONS = (
 					"POD_CONFIGURATION_DEBUG=1",
@@ -568,6 +601,7 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 6820F178C5F5E9638CACA2814BABA73E /* Pods-ScalingCarousel_Example.debug.xcconfig */;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				"CODE_SIGN_IDENTITY[sdk=appletvos*]" = "";
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "";
 				"CODE_SIGN_IDENTITY[sdk=watchos*]" = "";
@@ -594,6 +628,8 @@
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -626,7 +662,8 @@
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";

Example/Pods/Target Support Files/ScalingCarousel/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.0.2</string>
+	<string>2.0</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>

Example/ScalingCarousel.xcodeproj/project.pbxproj

@@ -245,16 +245,16 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0720;
-				LastUpgradeCheck = 0720;
+				LastUpgradeCheck = 0900;
 				ORGANIZATIONNAME = CocoaPods;
 				TargetAttributes = {
 					607FACCF1AFB9204008FA782 = {
 						CreatedOnToolsVersion = 6.3.1;
-						LastSwiftMigration = 0820;
+						LastSwiftMigration = 0900;
 					};
 					607FACE41AFB9204008FA782 = {
 						CreatedOnToolsVersion = 6.3.1;
-						LastSwiftMigration = 0820;
+						LastSwiftMigration = 0900;
 						TestTargetID = 607FACCF1AFB9204008FA782;
 					};
 				};
@@ -448,13 +448,21 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
@@ -493,13 +501,21 @@
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
 				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
@@ -518,6 +534,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				VALIDATE_PRODUCT = YES;
 			};
 			name = Release;
@@ -526,6 +543,7 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 54ACDAF6D64CCC3389CF9744 /* Pods-ScalingCarousel_Example.debug.xcconfig */;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				INFOPLIST_FILE = ScalingCarousel/Info.plist;
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
@@ -533,7 +551,8 @@
 				MODULE_NAME = ExampleApp;
 				PRODUCT_BUNDLE_IDENTIFIER = "org.cocoapods.demo.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -541,6 +560,7 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = C076B0D8341FA770E7E1424B /* Pods-ScalingCarousel_Example.release.xcconfig */;
 			buildSettings = {
+				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				INFOPLIST_FILE = ScalingCarousel/Info.plist;
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
@@ -548,7 +568,8 @@
 				MODULE_NAME = ExampleApp;
 				PRODUCT_BUNDLE_IDENTIFIER = "org.cocoapods.demo.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
@@ -568,7 +589,8 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "org.cocoapods.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -584,7 +606,8 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "org.cocoapods.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};

Example/ScalingCarousel.xcodeproj/xcshareddata/xcschemes/ScalingCarousel-Example.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0720"
+   LastUpgradeVersion = "0900"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -40,6 +40,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
          <TestableReference
@@ -69,6 +70,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"

Example/ScalingCarousel/Base.lproj/Main.storyboard

@@ -1,10 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="11762" systemVersion="16E144f" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES" initialViewController="jed-5q-J52">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="13122.19" systemVersion="16F73" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES" initialViewController="jed-5q-J52">
     <device id="retina4_7" orientation="portrait">
         <adaptation id="fullscreen"/>
     </device>
     <dependencies>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="11757"/>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="13104.16"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <scenes>
@@ -74,20 +75,29 @@
                                     <action selector="showHideButtonPressed:" destination="vXZ-lx-hvc" eventType="touchUpInside" id="Jsy-vc-cWp"/>
                                 </connections>
                             </button>
+                            <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="UYO-rO-XuZ">
+                                <rect key="frame" x="187" y="143" width="0.0" height="0.0"/>
+                                <fontDescription key="fontDescription" type="system" pointSize="17"/>
+                                <nil key="textColor"/>
+                                <nil key="highlightedColor"/>
+                            </label>
                         </subviews>
                         <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                         <constraints>
                             <constraint firstItem="Mq8-SH-Mx8" firstAttribute="width" secondItem="kh9-bI-dsS" secondAttribute="width" id="4Ux-ib-2uZ"/>
+                            <constraint firstItem="UYO-rO-XuZ" firstAttribute="centerX" secondItem="KAz-De-GJ8" secondAttribute="centerX" id="8U2-jX-Aw6"/>
                             <constraint firstItem="KAz-De-GJ8" firstAttribute="top" secondItem="jyV-Pf-zRb" secondAttribute="bottom" constant="85" id="Ffh-uk-Qnl"/>
                             <constraint firstItem="2fi-mo-0CV" firstAttribute="top" secondItem="Mq8-SH-Mx8" secondAttribute="bottom" constant="15" id="Kee-s5-jSC"/>
                             <constraint firstItem="KAz-De-GJ8" firstAttribute="centerX" secondItem="kh9-bI-dsS" secondAttribute="centerX" id="M5E-lE-5Pp"/>
                             <constraint firstItem="Mq8-SH-Mx8" firstAttribute="leading" secondItem="kh9-bI-dsS" secondAttribute="leading" id="NPp-qY-rgM"/>
+                            <constraint firstItem="UYO-rO-XuZ" firstAttribute="top" secondItem="KAz-De-GJ8" secondAttribute="bottom" constant="8" id="nfn-SZ-h6K"/>
                         </constraints>
                     </view>
                     <tabBarItem key="tabBarItem" title="Storyboard" id="7Ol-Hv-b1V"/>
                     <connections>
                         <outlet property="carousel" destination="Mq8-SH-Mx8" id="PYK-cv-2wb"/>
                         <outlet property="carouselBottomConstraint" destination="Kee-s5-jSC" id="HnZ-jP-gpN"/>
+                        <outlet property="output" destination="UYO-rO-XuZ" id="v8Z-xt-lyT"/>
                     </connections>
                 </viewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="x5A-6p-PRh" sceneMemberID="firstResponder"/>

Example/ScalingCarousel/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.0.2</string>
+	<string>2.0</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>

Example/ScalingCarousel/StoryboardViewController.swift

@@ -18,6 +18,7 @@ class StoryboardViewController: UIViewController {
     // MARK: - IBOutlets
     @IBOutlet weak var carousel: ScalingCarouselView!
     @IBOutlet weak var carouselBottomConstraint: NSLayoutConstraint!
+    @IBOutlet weak var output: UILabel!
     
     private struct Constants {
         static let carouselHideConstant: CGFloat = -250
@@ -65,5 +66,9 @@ extension StoryboardViewController: UICollectionViewDelegate {
     
     func scrollViewDidScroll(_ scrollView: UIScrollView) {
         carousel.didScroll()
+        
+        guard let currentCenterIndex = carousel.currentCenterCellIndex?.row else { return }
+        
+        output.text = String(describing: currentCenterIndex)
     }
 }

ScalingCarousel.podspec

@@ -8,7 +8,7 @@
 
 Pod::Spec.new do |s|
   s.name             = 'ScalingCarousel'
-  s.version          = '1.0.2'
+  s.version          = '2.0'
   s.summary          = 'A super simple carousel view with scaling transitions written in Swift'
 
   s.description      = <<-DESC

ScalingCarousel/Classes/ScalingCarouselView.swift

@@ -22,10 +22,40 @@ open class ScalingCarouselView: UICollectionView {
     /// Inset of the main, center cell
     @IBInspectable public var inset: CGFloat = 0.0 {
         didSet {
+            /*
+             Configure our layout, and add more
+             constraints to our invisible UIScrollView
+            */
             configureLayout()
         }
     }
     
+    /// Returns the current center cell of the carousel if it can be calculated
+    public var currentCenterCell: UICollectionViewCell? {
+        
+        let lowerBound = inset - 20
+        let upperBound = inset + 20
+        
+        for cell in visibleCells {
+            
+            let cellRect = convert(cell.frame, to: nil)
+            
+            if cellRect.origin.x > lowerBound && cellRect.origin.x < upperBound {
+                return cell
+            }
+            
+        }
+        
+        return nil
+    }
+    
+    /// Returns the IndexPath of the current center cell if it can be calculated
+    public var currentCenterCellIndex: IndexPath? {
+        guard let currentCenterCell = self.currentCenterCell else { return nil }
+        
+        return indexPath(for: currentCenterCell)
+    }
+    
     /// Override of the collection view content size to add an observer
     override open var contentSize: CGSize {
         didSet {
@@ -130,34 +160,62 @@ fileprivate extension PrivateAPI {
          This means touch events will fall through to the underlying UICollectionView
          */
         invisibleScrollView.isUserInteractionEnabled = false
-        /// Set the scroll delegate to be our UICollectionView
+        
+        /// Set the scroll delegate to be the ScalingCarouselView
         invisibleScrollView.delegate = self
+        
         /*
-         Now add the disabled scrollviews pan gesture recognizer to our collection view
+         Now add the invisible scrollview's pan 
+         gesture recognizer to the ScalingCarouselView
          */
         addGestureRecognizer(invisibleScrollView.panGestureRecognizer)
-        /// Finally, add the 'invisible' scrollview as a subview
+        
+        /*
+         Finally, add the 'invisible' scrollview as a subview 
+         of the ScalingCarousel's superview
+        */
         superview.addSubview(invisibleScrollView)
         
-        // Add constraints
+        /*
+         Add constraints for height and top, relative to the
+         ScalingCarouselView
+        */
         invisibleScrollView.heightAnchor.constraint(equalTo: heightAnchor).isActive = true
         invisibleScrollView.topAnchor.constraint(equalTo: topAnchor).isActive = true
         
+        /*
+         Further configure our layout and add more constraints
+         for width and left position
+        */
         configureLayout()
     }
     
     fileprivate func configureLayout() {
-        collectionViewLayout = ScalingCarouselLayout(withCarouselInset: inset)
         
+        // Create a ScalingCarouselLayout using our inset
+        collectionViewLayout = ScalingCarouselLayout(
+            withCarouselInset: inset)
+        
+        /*
+         Only continue if we have a reference to
+         our 'invisible' UIScrollView
+        */
         guard let invisibleScrollView = invisibleScrollView else { return }
     
         // Remove constraints if they already exist
         invisibleWidthConstraint?.isActive = false
         invisibleLeftConstraint?.isActive = false
         
-        invisibleWidthConstraint = invisibleScrollView.widthAnchor.constraint(equalTo: widthAnchor, constant: -(2 * inset))
-        invisibleLeftConstraint =  invisibleScrollView.leftAnchor.constraint(equalTo: leftAnchor, constant: inset)
+        /* 
+         Add constrants for width and left postion 
+         to our 'invisible' UIScrollView
+        */
+        invisibleWidthConstraint = invisibleScrollView.widthAnchor.constraint(
+            equalTo: widthAnchor, constant: -(2 * inset))
+        invisibleLeftConstraint =  invisibleScrollView.leftAnchor.constraint(
+            equalTo: leftAnchor, constant: inset)
         
+        // Activate the constraints
         invisibleWidthConstraint?.isActive = true
         invisibleLeftConstraint?.isActive = true
     }
@@ -177,7 +235,7 @@ extension InvisibleScrollDelegate: UIScrollViewDelegate {
         */
         updateOffSet()
         
-        // Scale Visible cells
+        // Also, this is where we scale our cells
         for cell in visibleCells {
             if let infoCardCell = cell as? ScalingCarouselCell {
                 infoCardCell.scale(withCarouselInset: inset)