diff --git a/.swift-version b/.swift-version
index 9f55b2c..5186d07 100644
--- a/.swift-version
+++ b/.swift-version
@@ -1 +1 @@
-3.0
+4.0
diff --git a/KYNavigationProgress.podspec b/KYNavigationProgress.podspec
index 68b98a2..b9200bf 100644
--- a/KYNavigationProgress.podspec
+++ b/KYNavigationProgress.podspec
@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "KYNavigationProgress"
-  s.version      = "2.0.1"
+  s.version      = "2.0.2"
   s.summary      = "KYNavigationProgress is simple extension of UINavigationController to display progress on the UINavigationBar."
   s.homepage     = "https://github.com/ykyouhei/KYNavigationProgress"
   s.license      = "MIT"
diff --git a/KYNavigationProgress.xcodeproj/project.pbxproj b/KYNavigationProgress.xcodeproj/project.pbxproj
index dd00aff..8594244 100644
--- a/KYNavigationProgress.xcodeproj/project.pbxproj
+++ b/KYNavigationProgress.xcodeproj/project.pbxproj
@@ -182,11 +182,12 @@
 				TargetAttributes = {
 					C2A91C121C32782F006D1CAE = {
 						CreatedOnToolsVersion = 7.2;
-						LastSwiftMigration = 0800;
+						LastSwiftMigration = 0900;
 						ProvisioningStyle = Automatic;
 					};
 					C2A91C301C327872006D1CAE = {
 						CreatedOnToolsVersion = 7.2;
+						LastSwiftMigration = 0900;
 					};
 				};
 			};
@@ -392,7 +393,8 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -413,7 +415,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.kyo--hei.KYNavigationProgress";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 3.0;
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
@@ -428,6 +431,8 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.kyo--hei.Sample";
 				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Debug;
 		};
@@ -442,6 +447,8 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.kyo--hei.Sample";
 				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_SWIFT3_OBJC_INFERENCE = On;
+				SWIFT_VERSION = 4.0;
 			};
 			name = Release;
 		};
diff --git a/KYNavigationProgress/Info.plist b/KYNavigationProgress/Info.plist
index 783e22e..a16c895 100644
--- a/KYNavigationProgress/Info.plist
+++ b/KYNavigationProgress/Info.plist
@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.0.1</string>
+	<string>2.0.2</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
diff --git a/KYNavigationProgress/ProgressView.swift b/KYNavigationProgress/ProgressView.swift
index 4a745ff..23d0c99 100644
--- a/KYNavigationProgress/ProgressView.swift
+++ b/KYNavigationProgress/ProgressView.swift
@@ -23,13 +23,13 @@ public final class ProgressView: UIView {
 	
 	internal let bar = UIView()
 	
-	public dynamic var progressTintColor: UIColor? = UIColor(red: 0, green: 122/255, blue: 1, alpha: 1) {
+	@objc public dynamic var progressTintColor: UIColor? = UIColor(red: 0, green: 122/255, blue: 1, alpha: 1) {
 		didSet {
 			bar.backgroundColor = progressTintColor
 		}
 	}
 	
-	public dynamic var trackTintColor: UIColor? = .clear {
+	@objc public dynamic var trackTintColor: UIColor? = .clear {
 		didSet {
 			backgroundColor = trackTintColor
 		}