diff --git a/Spring/DesignableTabBarController.swift b/Spring/DesignableTabBarController.swift
index f75fbcc..6c81095 100644
--- a/Spring/DesignableTabBarController.swift
+++ b/Spring/DesignableTabBarController.swift
@@ -47,7 +47,7 @@ import UIKit
     @IBInspectable var firstSelectedImage: UIImage? {
         didSet {
             if let image = firstSelectedImage {
-                var tabBarItems = self.tabBar.items as [UITabBarItem]!
+                var tabBarItems = self.tabBar.items as [UITabBarItem]?
                 tabBarItems?[0].selectedImage = image.withRenderingMode(UIImage.RenderingMode.alwaysTemplate)
             }
         }
@@ -56,7 +56,7 @@ import UIKit
     @IBInspectable var secondSelectedImage: UIImage? {
         didSet {
             if let image = secondSelectedImage {
-                var tabBarItems = self.tabBar.items as [UITabBarItem]!
+                var tabBarItems = self.tabBar.items as [UITabBarItem]?
                 tabBarItems?[1].selectedImage = image.withRenderingMode(UIImage.RenderingMode.alwaysTemplate)
             }
         }
@@ -65,7 +65,7 @@ import UIKit
     @IBInspectable var thirdSelectedImage: UIImage? {
         didSet {
             if let image = thirdSelectedImage {
-                var tabBarItems = self.tabBar.items as [UITabBarItem]!
+                var tabBarItems = self.tabBar.items as [UITabBarItem]?
                 tabBarItems?[2].selectedImage = image.withRenderingMode(UIImage.RenderingMode.alwaysTemplate)
             }
         }
@@ -74,7 +74,7 @@ import UIKit
     @IBInspectable var fourthSelectedImage: UIImage? {
         didSet {
             if let image = fourthSelectedImage {
-                var tabBarItems = self.tabBar.items as [UITabBarItem]!
+                var tabBarItems = self.tabBar.items as [UITabBarItem]?
                 tabBarItems?[3].selectedImage = image.withRenderingMode(UIImage.RenderingMode.alwaysTemplate)
             }
         }
@@ -83,7 +83,7 @@ import UIKit
     @IBInspectable var fifthSelectedImage: UIImage? {
         didSet {
             if let image = fifthSelectedImage {
-                var tabBarItems = self.tabBar.items as [UITabBarItem]!
+                var tabBarItems = self.tabBar.items as [UITabBarItem]?
                 tabBarItems?[4].selectedImage = image.withRenderingMode(UIImage.RenderingMode.alwaysTemplate)
             }
         }
@@ -91,10 +91,11 @@ import UIKit
     
     override func viewDidLoad() {
         super.viewDidLoad()
-        
-        for item in self.tabBar.items as [UITabBarItem]! {
-            if let image = item.image {
-                item.image = image.imageWithColor(tintColor: self.normalTint).withRenderingMode(UIImage.RenderingMode.alwaysOriginal)
+        if let items = self.tabBar.items {
+            for item in items {
+                if let image = item.image {
+                    item.image = image.imageWithColor(tintColor: self.normalTint).withRenderingMode(UIImage.RenderingMode.alwaysOriginal)
+                }
             }
         }
     }
diff --git a/Spring/Misc.swift b/Spring/Misc.swift
index c0a9add..96024b8 100644
--- a/Spring/Misc.swift
+++ b/Spring/Misc.swift
@@ -23,9 +23,9 @@
 import UIKit
 
 public extension String {
-    public var length: Int { return self.characters.count }
+    var length: Int { return self.count }
     
-    public func toURL() -> NSURL? {
+    func toURL() -> NSURL? {
         return NSURL(string: self)
     }
 }
@@ -73,7 +73,7 @@ public extension UIColor {
         let scanner = Scanner(string: hex)
         var hexValue: CUnsignedLongLong = 0
         if scanner.scanHexInt64(&hexValue) {
-            switch (hex.characters.count) {
+            switch (hex.count) {
             case 3:
                 red   = CGFloat((hexValue & 0xF00) >> 8)       / 15.0
                 green = CGFloat((hexValue & 0x0F0) >> 4)       / 15.0
diff --git a/SpringApp.xcodeproj/project.pbxproj b/SpringApp.xcodeproj/project.pbxproj
index 8e701c1..a0e8956 100644
--- a/SpringApp.xcodeproj/project.pbxproj
+++ b/SpringApp.xcodeproj/project.pbxproj
@@ -413,20 +413,20 @@
 				TargetAttributes = {
 					1A4FDA321A6E44780099D309 = {
 						CreatedOnToolsVersion = 6.1.1;
-						LastSwiftMigration = 0900;
+						LastSwiftMigration = 1020;
 					};
 					1A4FDA3C1A6E44780099D309 = {
 						CreatedOnToolsVersion = 6.1.1;
-						LastSwiftMigration = 0900;
+						LastSwiftMigration = 1020;
 						TestTargetID = 9641173A1A5BE90A000E3A5A;
 					};
 					9641173A1A5BE90A000E3A5A = {
 						CreatedOnToolsVersion = 6.2;
-						LastSwiftMigration = 0900;
+						LastSwiftMigration = 1020;
 					};
 					9641174F1A5BE90A000E3A5A = {
 						CreatedOnToolsVersion = 6.2;
-						LastSwiftMigration = 0900;
+						LastSwiftMigration = 1020;
 						TestTargetID = 9641173A1A5BE90A000E3A5A;
 					};
 				};
@@ -436,6 +436,7 @@
 			developmentRegion = English;
 			hasScannedForEncodings = 0;
 			knownRegions = (
+				English,
 				en,
 				Base,
 			);
@@ -615,8 +616,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "designcode.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -640,8 +640,7 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -660,8 +659,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.jamztang.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.0;
+				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/SpringApp.app/SpringApp";
 			};
 			name = Debug;
@@ -675,8 +673,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.jamztang.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.0;
+				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/SpringApp.app/SpringApp";
 			};
 			name = Release;
@@ -788,8 +785,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "designcode.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
 			name = Debug;
@@ -804,8 +800,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "designcode.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
 			name = Release;
@@ -822,8 +817,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "designcode.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.0;
+				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/SpringApp.app/SpringApp";
 			};
 			name = Debug;
@@ -837,8 +831,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "designcode.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
-				SWIFT_SWIFT3_OBJC_INFERENCE = Off;
-				SWIFT_VERSION = 4.0;
+				SWIFT_VERSION = 5.0;
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/SpringApp.app/SpringApp";
 			};
 			name = Release;