diff --git a/android/app/src/main/AndroidManifest.xml b/android/app/src/main/AndroidManifest.xml
index 3f54978f..a8f1f8ce 100644
--- a/android/app/src/main/AndroidManifest.xml
+++ b/android/app/src/main/AndroidManifest.xml
@@ -6,7 +6,7 @@
          additional functionality it is fine to subclass or reimplement
          FlutterApplication and put your custom class here. -->
     <application
-        android:name="io.flutter.app.FlutterApplication"
+        android:name="${applicationName}"
         android:label="persistent_bottom_nav_bar"
         android:icon="@mipmap/ic_launcher">
         <activity
diff --git a/example/android/app/src/main/AndroidManifest.xml b/example/android/app/src/main/AndroidManifest.xml
index 8bc6007d..934a0c0d 100644
--- a/example/android/app/src/main/AndroidManifest.xml
+++ b/example/android/app/src/main/AndroidManifest.xml
@@ -6,7 +6,7 @@
          additional functionality it is fine to subclass or reimplement
          FlutterApplication and put your custom class here. -->
     <application
-        android:name="io.flutter.app.FlutterApplication"
+        android:name="${applicationName}"
         android:label="example"
         android:icon="@mipmap/ic_launcher">
         <activity
diff --git a/example/pubspec.lock b/example/pubspec.lock
index 9e9ce622..e073cc1e 100644
--- a/example/pubspec.lock
+++ b/example/pubspec.lock
@@ -7,7 +7,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0"
+    version: "2.8.2"
   boolean_selector:
     dependency: transitive
     description:
@@ -21,14 +21,14 @@ packages:
       name: characters
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0"
+    version: "1.2.0"
   charcode:
     dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0"
+    version: "1.3.1"
   clock:
     dependency: transitive
     description:
@@ -42,14 +42,14 @@ packages:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0"
+    version: "1.16.0"
   fake_async:
     dependency: transitive
     description:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0"
+    version: "1.3.0"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -66,28 +66,35 @@ packages:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.10"
+    version: "0.12.11"
+  material_color_utilities:
+    dependency: transitive
+    description:
+      name: material_color_utilities
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.1.4"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0"
+    version: "1.7.0"
   path:
     dependency: transitive
     description:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   persistent_bottom_nav_bar:
     dependency: "direct dev"
     description:
       path: ".."
       relative: true
     source: path
-    version: "4.0.2"
+    version: "4.0.3"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -99,7 +106,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.2"
   stack_trace:
     dependency: transitive
     description:
@@ -134,20 +141,13 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19"
-  typed_data:
-    dependency: transitive
-    description:
-      name: typed_data
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.3.0"
+    version: "0.4.9"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0"
+    version: "2.1.2"
 sdks:
-  dart: ">=2.12.0 <3.0.0"
+  dart: ">=2.17.0 <3.0.0"
diff --git a/lib/animations/animations.dart b/lib/animations/animations.dart
index 36cc6f4f..7243f985 100644
--- a/lib/animations/animations.dart
+++ b/lib/animations/animations.dart
@@ -52,7 +52,7 @@ class _OffsetAnimationState extends State<OffsetAnimation>
   }
 
   _hideAnimation() {
-    WidgetsBinding.instance!.addPostFrameCallback((_) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
       if (_hideNavigationBar!) {
         _navBarHideAnimationController.forward();
       } else {
diff --git a/lib/nav-bar-styles/style-11-bottom-nav-bar.widget.dart b/lib/nav-bar-styles/style-11-bottom-nav-bar.widget.dart
index 14379350..c42c6857 100644
--- a/lib/nav-bar-styles/style-11-bottom-nav-bar.widget.dart
+++ b/lib/nav-bar-styles/style-11-bottom-nav-bar.widget.dart
@@ -43,7 +43,7 @@ class _BottomNavStyle11State extends State<BottomNavStyle11>
           .animate(_animationControllerList[i]));
     }
 
-    WidgetsBinding.instance!.addPostFrameCallback((_) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
       _animationControllerList[_selectedIndex!].forward();
     });
   }
diff --git a/lib/nav-bar-styles/style-12-bottom-nav-bar.widget.dart b/lib/nav-bar-styles/style-12-bottom-nav-bar.widget.dart
index f748cf99..2a2b5841 100644
--- a/lib/nav-bar-styles/style-12-bottom-nav-bar.widget.dart
+++ b/lib/nav-bar-styles/style-12-bottom-nav-bar.widget.dart
@@ -43,7 +43,7 @@ class _BottomNavStyle12State extends State<BottomNavStyle12>
           .animate(_animationControllerList[i]));
     }
 
-    WidgetsBinding.instance!.addPostFrameCallback((_) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
       _animationControllerList[_selectedIndex!].forward();
     });
   }
diff --git a/lib/nav-bar-styles/style-13-bottom-nav-bar.widget.dart b/lib/nav-bar-styles/style-13-bottom-nav-bar.widget.dart
index 344226cc..450932e7 100644
--- a/lib/nav-bar-styles/style-13-bottom-nav-bar.widget.dart
+++ b/lib/nav-bar-styles/style-13-bottom-nav-bar.widget.dart
@@ -43,7 +43,7 @@ class _BottomNavStyle13State extends State<BottomNavStyle13>
           .animate(_animationControllerList[i]));
     }
 
-    WidgetsBinding.instance!.addPostFrameCallback((_) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
       _animationControllerList[_selectedIndex!].forward();
     });
   }
diff --git a/lib/nav-bar-styles/style-14-bottom-nav-bar.widget.dart b/lib/nav-bar-styles/style-14-bottom-nav-bar.widget.dart
index 2d608b1d..d12005f7 100644
--- a/lib/nav-bar-styles/style-14-bottom-nav-bar.widget.dart
+++ b/lib/nav-bar-styles/style-14-bottom-nav-bar.widget.dart
@@ -43,7 +43,7 @@ class _BottomNavStyle14State extends State<BottomNavStyle14>
           .animate(_animationControllerList[i]));
     }
 
-    WidgetsBinding.instance!.addPostFrameCallback((_) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
       _animationControllerList[_selectedIndex!].forward();
     });
   }
diff --git a/lib/nav-bar-styles/style-6-bottom-nav-bar.widget.dart b/lib/nav-bar-styles/style-6-bottom-nav-bar.widget.dart
index 1fc1e0a3..1886392f 100644
--- a/lib/nav-bar-styles/style-6-bottom-nav-bar.widget.dart
+++ b/lib/nav-bar-styles/style-6-bottom-nav-bar.widget.dart
@@ -41,7 +41,7 @@ class _BottomNavStyle6State extends State<BottomNavStyle6>
           .animate(_animationControllerList[i]));
     }
 
-    WidgetsBinding.instance!.addPostFrameCallback((_) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
       _animationControllerList[_selectedIndex!].forward();
     });
   }
diff --git a/lib/nav-bar-styles/style-8-bottom-nav-bar.widget.dart b/lib/nav-bar-styles/style-8-bottom-nav-bar.widget.dart
index bae36f56..ed6b56de 100644
--- a/lib/nav-bar-styles/style-8-bottom-nav-bar.widget.dart
+++ b/lib/nav-bar-styles/style-8-bottom-nav-bar.widget.dart
@@ -41,7 +41,7 @@ class _BottomNavStyle8State extends State<BottomNavStyle8>
           .animate(_animationControllerList[i]));
     }
 
-    WidgetsBinding.instance!.addPostFrameCallback((_) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
       _animationControllerList[_selectedIndex!].forward();
     });
   }
diff --git a/lib/persistent-tab-view.widget.dart b/lib/persistent-tab-view.widget.dart
index 9b359c62..f458d3c0 100644
--- a/lib/persistent-tab-view.widget.dart
+++ b/lib/persistent-tab-view.widget.dart
@@ -365,7 +365,7 @@ class _PersistentTabViewState extends State<PersistentTabView> {
       }
     });
     if (widget.selectedTabScreenContext != null) {
-      WidgetsBinding.instance!.addPostFrameCallback((_) {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
         widget.selectedTabScreenContext!(_contextList[_controller!.index]);
       });
     }
diff --git a/pubspec.lock b/pubspec.lock
index 49a0ce66..8a19e739 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -7,7 +7,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0"
+    version: "2.8.2"
   boolean_selector:
     dependency: transitive
     description:
@@ -21,14 +21,14 @@ packages:
       name: characters
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0"
+    version: "1.2.0"
   charcode:
     dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0"
+    version: "1.3.1"
   clock:
     dependency: transitive
     description:
@@ -42,14 +42,14 @@ packages:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0"
+    version: "1.16.0"
   fake_async:
     dependency: transitive
     description:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0"
+    version: "1.3.0"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -66,21 +66,28 @@ packages:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.10"
+    version: "0.12.11"
+  material_color_utilities:
+    dependency: transitive
+    description:
+      name: material_color_utilities
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.1.4"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0"
+    version: "1.7.0"
   path:
     dependency: transitive
     description:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -92,7 +99,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.2"
   stack_trace:
     dependency: transitive
     description:
@@ -127,20 +134,13 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19"
-  typed_data:
-    dependency: transitive
-    description:
-      name: typed_data
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.3.0"
+    version: "0.4.9"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0"
+    version: "2.1.2"
 sdks:
-  dart: ">=2.12.0 <3.0.0"
+  dart: ">=2.17.0 <3.0.0"
diff --git a/pubspec.yaml b/pubspec.yaml
index 9f7edf66..385fa3d6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -3,10 +3,10 @@ description: A do all, highly customizable persistent/static bottom navigation b
 
 homepage: https://github.com/BilalShahid13/PersistentBottomNavBar
 repository: https://github.com/BilalShahid13/PersistentBottomNavBar
-version: 4.0.2
+version: 4.0.3
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: '>=2.17.0 <3.0.0'
 
 dependencies:
   flutter: