Bump the Swift version to 4.0 and min OS to 9.0.

Podfile

@@ -1,6 +1,6 @@
 workspace 'MotionTransitioning.xcworkspace'
 use_frameworks!
-platform :ios, '8.0'
+platform :ios, '9.0'
 
 target "TransitionsCatalog" do
   pod 'CatalogByConvention'

Podfile.lock

@@ -18,6 +18,6 @@ SPEC CHECKSUMS:
   CatalogByConvention: c3a5319de04250a7cd4649127fcfca5fe3322a43
   MotionTransitioning: afdc2fb08fc6e8744dab4f160b3764c9bde59338
 
-PODFILE CHECKSUM: 25d5942fb7698339a03667bb46c3fbb77529b92d
+PODFILE CHECKSUM: c1fb58e87919bf8979e1ee2b4db99797e975d789
 
 COCOAPODS: 1.6.0

examples/ContextualExample.swift

@@ -21,7 +21,7 @@ import MotionTransitioning
 
 class ContextualExampleViewController: ExampleViewController {
 
-  func didTap(_ tapGesture: UITapGestureRecognizer) {
+  @objc func didTap(_ tapGesture: UITapGestureRecognizer) {
     let controller = DestinationViewController()
 
     // A contextual transition is provided with information relevant to the transition, such as the
@@ -142,7 +142,7 @@ private class DestinationViewController: ExampleViewController {
     view.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(didTap)))
   }
 
-  func didTap() {
+  @objc func didTap() {
     dismiss(animated: true)
   }
 }

examples/FadeExample.m

@@ -43,7 +43,7 @@ - (void)didTap {
 - (void)viewDidLoad {
   [super viewDidLoad];
 
-  self.view.backgroundColor = [UIColor backgroundColor];
+  self.view.backgroundColor = [UIColor whiteColor];
 
   UILabel *label = [[UILabel alloc] initWithFrame:self.view.bounds];
   label.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;

examples/FadeExample.swift

@@ -22,7 +22,7 @@ import MotionTransitioning
 
 class FadeExampleViewController: ExampleViewController {
 
-  func didTap() {
+  @objc func didTap() {
     let modalViewController = ModalViewController()
 
     // The transition controller is an associated object on all UIViewController instances that

examples/MenuExample.swift

@@ -19,7 +19,7 @@ import MotionTransitioning
 
 class MenuExampleViewController: ExampleViewController {
 
-  func didTap() {
+  @objc func didTap() {
     let modalViewController = ModalViewController()
     modalViewController.mdm_transitionController.transition = MenuTransition()
     present(modalViewController, animated: true)

examples/NavControllerFadeExample.swift

@@ -22,7 +22,7 @@ import MotionTransitioning
 
 class NavControllerFadeExampleViewController: ExampleViewController {
 
-  func didTap() {
+  @objc func didTap() {
     let modalViewController = ModalViewController()
     modalViewController.title = "Example view controller"
 

examples/apps/Catalog/TableOfContents.swift

@@ -14,28 +14,30 @@
  limitations under the License.
  */
 
+import Foundation
+
 // MARK: Catalog by convention
 
 extension ContextualExampleViewController {
-  class func catalogBreadcrumbs() -> [String] { return ["Contextual transition"] }
+  @objc class func catalogBreadcrumbs() -> [String] { return ["Contextual transition"] }
 }
 
 extension FadeExampleViewController {
-  class func catalogBreadcrumbs() -> [String] { return ["Fade transition"] }
+  @objc class func catalogBreadcrumbs() -> [String] { return ["Fade transition"] }
 }
 
 extension NavControllerFadeExampleViewController {
-  class func catalogBreadcrumbs() -> [String] { return ["Fade transition (nav controller)"] }
+  @objc class func catalogBreadcrumbs() -> [String] { return ["Fade transition (nav controller)"] }
 }
 
 extension MenuExampleViewController {
-  class func catalogBreadcrumbs() -> [String] { return ["Menu transition"] }
+  @objc class func catalogBreadcrumbs() -> [String] { return ["Menu transition"] }
 }
 
 extension PhotoAlbumExampleViewController {
-  class func catalogBreadcrumbs() -> [String] { return ["Photo album transition"] }
+  @objc class func catalogBreadcrumbs() -> [String] { return ["Photo album transition"] }
 }
 
 extension CustomPresentationExampleViewController {
-  class func catalogBreadcrumbs() -> [String] { return ["Custom presentation transitions"] }
+  @objc class func catalogBreadcrumbs() -> [String] { return ["Custom presentation transitions"] }
 }

examples/apps/Catalog/TransitionsCatalog.xcodeproj/project.pbxproj

@@ -447,6 +447,7 @@
 			developmentRegion = English;
 			hasScannedForEncodings = 0;
 			knownRegions = (
+				English,
 				en,
 				Base,
 			);
@@ -709,6 +710,7 @@
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = iphoneos;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
 			name = Debug;
@@ -755,6 +757,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
+				SWIFT_VERSION = 4.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VALIDATE_PRODUCT = YES;
 			};
@@ -771,7 +774,6 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.Catalog;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
 			};
 			name = Debug;
 		};
@@ -786,7 +788,6 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.Catalog;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
 			};
 			name = Release;
 		};
@@ -802,7 +803,6 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.CatalogTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/TestHarness.app/TestHarness";
 			};
 			name = Debug;
@@ -819,7 +819,6 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.CatalogTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/TestHarness.app/TestHarness";
 			};
 			name = Release;
@@ -836,7 +835,6 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.TestHarness;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
-				SWIFT_VERSION = 3.0;
 			};
 			name = Debug;
 		};
@@ -852,7 +850,6 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.TestHarness;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_VERSION = 3.0;
 			};
 			name = Release;
 		};

examples/supplemental/ModalViewController.swift

@@ -38,7 +38,7 @@ class ModalViewController: ExampleViewController {
     return .lightContent
   }
 
-  func didTap() {
+  @objc func didTap() {
     dismiss(animated: true)
   }
 }