diff --git a/Example/AppDelegate.swift b/Example/AppDelegate.swift
index 201e483..061c40a 100644
--- a/Example/AppDelegate.swift
+++ b/Example/AppDelegate.swift
@@ -14,7 +14,7 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
     var window: UIWindow?
 
 
-    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
+    internal func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
         // Override point for customization after application launch.
         return true
     }
diff --git a/Example/ViewController.swift b/Example/ViewController.swift
index fbf9df2..8978bf9 100644
--- a/Example/ViewController.swift
+++ b/Example/ViewController.swift
@@ -19,20 +19,20 @@ class ViewController: UIViewController {
     
     override func viewWillAppear(_ animated: Bool) {
         super.viewWillAppear(animated)
-        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(notification:)), name: NSNotification.Name.UIKeyboardDidShow, object: nil)
-        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
+        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(notification:)), name: UIResponder.keyboardDidShowNotification, object: nil)
+        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(notification:)), name: UIResponder.keyboardWillHideNotification, object: nil)
     }
     
     override func viewWillDisappear(_ animated: Bool) {
         super.viewWillDisappear(animated)
-        NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardDidShow, object: nil)
-        NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
+        NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardDidShowNotification, object: nil)
+        NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
     }
     
-    func keyboardWasShown(notification: NSNotification)
+    @objc func keyboardWasShown(notification: NSNotification)
     {
         let info = notification.userInfo!
-        var kbRect = (info[UIKeyboardFrameEndUserInfoKey]! as! NSValue).cgRectValue
+        var kbRect = (info[UIResponder.keyboardFrameEndUserInfoKey]! as! NSValue).cgRectValue
         kbRect = view.convert(kbRect, from: nil)
         
         var contentInsets = placeholderTextView.contentInset
@@ -41,7 +41,7 @@ class ViewController: UIViewController {
         placeholderTextView.scrollIndicatorInsets = contentInsets
     }
     
-    func keyboardWillBeHidden(notification: NSNotification)
+    @objc func keyboardWillBeHidden(notification: NSNotification)
     {
         var contentInsets = placeholderTextView.contentInset
         contentInsets.bottom = 0.0
diff --git a/KMPlaceholderTextView.xcodeproj/project.pbxproj b/KMPlaceholderTextView.xcodeproj/project.pbxproj
index 43aaab4..942e506 100644
--- a/KMPlaceholderTextView.xcodeproj/project.pbxproj
+++ b/KMPlaceholderTextView.xcodeproj/project.pbxproj
@@ -254,7 +254,7 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0700;
-				LastUpgradeCheck = 0900;
+				LastUpgradeCheck = 1020;
 				ORGANIZATIONNAME = "Zhouqi Mo";
 				TargetAttributes = {
 					CD2064EF1AA18E6900E1F272 = {
@@ -263,7 +263,7 @@
 					};
 					CD2BEB821B809B7B00EC1567 = {
 						CreatedOnToolsVersion = 6.4;
-						LastSwiftMigration = 0900;
+						LastSwiftMigration = 1020;
 					};
 					CD2BEB8C1B809B7B00EC1567 = {
 						CreatedOnToolsVersion = 6.4;
@@ -273,7 +273,7 @@
 			};
 			buildConfigurationList = CD2064EB1AA18E6900E1F272 /* Build configuration list for PBXProject "KMPlaceholderTextView" */;
 			compatibilityVersion = "Xcode 3.2";
-			developmentRegion = English;
+			developmentRegion = en;
 			hasScannedForEncodings = 0;
 			knownRegions = (
 				en,
@@ -387,6 +387,7 @@
 			isa = XCBuildConfiguration;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_LOCALIZABILITY_NONLOCALIZED = YES;
 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
@@ -395,12 +396,14 @@
 				CLANG_WARN_BOOL_CONVERSION = YES;
 				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DEPRECATED_OBJC_IMPLEMENTATIONS = 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_IMPLICIT_RETAIN_SELF = YES;
 				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
 				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
@@ -440,6 +443,7 @@
 			isa = XCBuildConfiguration;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_LOCALIZABILITY_NONLOCALIZED = YES;
 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
 				CLANG_CXX_LIBRARY = "libc++";
 				CLANG_ENABLE_MODULES = YES;
@@ -448,12 +452,14 @@
 				CLANG_WARN_BOOL_CONVERSION = YES;
 				CLANG_WARN_COMMA = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DEPRECATED_OBJC_IMPLEMENTATIONS = 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_IMPLICIT_RETAIN_SELF = YES;
 				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
 				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
@@ -490,7 +496,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.mo.kmplaceholdertextview.example;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
@@ -502,7 +508,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = com.mo.kmplaceholdertextview.example;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 3.0;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Release;
 		};
@@ -528,8 +534,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.mo.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
-				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -555,8 +560,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = "com.mo.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
-				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
diff --git a/KMPlaceholderTextView.xcodeproj/xcshareddata/xcschemes/KMPlaceholderTextView.xcscheme b/KMPlaceholderTextView.xcodeproj/xcshareddata/xcschemes/KMPlaceholderTextView.xcscheme
index 08286d3..a6db8e8 100644
--- a/KMPlaceholderTextView.xcodeproj/xcshareddata/xcschemes/KMPlaceholderTextView.xcscheme
+++ b/KMPlaceholderTextView.xcodeproj/xcshareddata/xcschemes/KMPlaceholderTextView.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0900"
+   LastUpgradeVersion = "1020"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -26,7 +26,6 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
       </Testables>
@@ -37,7 +36,6 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"