diff --git a/.gitignore b/.gitignore
index 1985397..4655c8a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -29,6 +29,7 @@
 .pub-cache/
 .pub/
 build/
+pubspec.lock
 
 # Android related
 **/android/**/gradle-wrapper.jar
diff --git a/example/android/app/build.gradle b/example/android/app/build.gradle
index 6ca2344..2aebba3 100644
--- a/example/android/app/build.gradle
+++ b/example/android/app/build.gradle
@@ -1,3 +1,9 @@
+plugins {
+    id "com.android.application"
+    id "kotlin-android"
+    id "dev.flutter.flutter-gradle-plugin"
+}
+
 def localProperties = new Properties()
 def localPropertiesFile = rootProject.file('local.properties')
 if (localPropertiesFile.exists()) {
@@ -6,11 +12,6 @@ if (localPropertiesFile.exists()) {
     }
 }
 
-def flutterRoot = localProperties.getProperty('flutter.sdk')
-if (flutterRoot == null) {
-    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
-}
-
 def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
 if (flutterVersionCode == null) {
     flutterVersionCode = '1'
@@ -21,30 +22,46 @@ if (flutterVersionName == null) {
     flutterVersionName = '1.0'
 }
 
-apply plugin: 'com.android.application'
-apply plugin: 'kotlin-android'
-apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
-    compileSdkVersion 30
+    namespace "com.example.example"
+    compileSdk 34
+    ndkVersion "25.1.8937393"
+
+    compileOptions {
+        coreLibraryDesugaringEnabled true
+
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    kotlinOptions {
+        jvmTarget = '1.8'
+    }
 
     sourceSets {
         main.java.srcDirs += 'src/main/kotlin'
     }
 
+    buildFeatures {
+        buildConfig = true
+    }
+
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
         applicationId "com.example.example"
-        minSdkVersion 16
-        targetSdkVersion 30
+        // You can update the following values to match your application needs.
+        // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-gradle-build-configuration.
+        minSdkVersion 23
+        targetSdkVersion flutter.targetSdkVersion
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
     }
 
+
     buildTypes {
         release {
-            // TODO: Add your own signing config for the release build.
-            // Signing with the debug keys for now, so `flutter run --release` works.
+//            signingConfig signingConfigs.release
             signingConfig signingConfigs.debug
         }
     }
@@ -55,5 +72,7 @@ flutter {
 }
 
 dependencies {
-    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+
+    coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:2.0.4'
+
 }
diff --git a/example/android/app/src/debug/AndroidManifest.xml b/example/android/app/src/debug/AndroidManifest.xml
index c208884..892d4b3 100644
--- a/example/android/app/src/debug/AndroidManifest.xml
+++ b/example/android/app/src/debug/AndroidManifest.xml
@@ -1,7 +1,6 @@
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.example">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
     <!-- Flutter needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->
-    <uses-permission android:name="android.permission.INTERNET"/>
+    <uses-permission android:name="android.permission.INTERNET" />
 </manifest>
diff --git a/example/android/app/src/main/AndroidManifest.xml b/example/android/app/src/main/AndroidManifest.xml
index 34dd77e..226cfbb 100644
--- a/example/android/app/src/main/AndroidManifest.xml
+++ b/example/android/app/src/main/AndroidManifest.xml
@@ -1,35 +1,33 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.example">
-   <application
-        android:label="example"
-        android:icon="@mipmap/ic_launcher">
+    xmlns:tools="http://schemas.android.com/tools"
+    android:installLocation="preferExternal">
+
+    <uses-permission android:name="android.permission.INTERNET" />
+
+    <application
+        android:name="${applicationName}"
+        android:icon="@mipmap/ic_launcher"
+        android:label="HappyLand"
+        android:requestLegacyExternalStorage="true">
+
         <activity
             android:name=".MainActivity"
-            android:launchMode="singleTop"
-            android:theme="@style/LaunchTheme"
             android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:exported="true"
             android:hardwareAccelerated="true"
+            android:launchMode="singleTop"
+            android:theme="@style/LaunchTheme"
             android:windowSoftInputMode="adjustResize">
             <!-- Specifies an Android theme to apply to this Activity as soon as
                  the Android process has started. This theme is visible to the user
                  while the Flutter UI initializes. After that, this theme continues
                  to determine the Window background behind the Flutter UI. -->
             <meta-data
-              android:name="io.flutter.embedding.android.NormalTheme"
-              android:resource="@style/NormalTheme"
-              />
-            <!-- Displays an Android View that continues showing the launch screen
-                 Drawable until Flutter paints its first frame, then this splash
-                 screen fades out. A splash screen is useful to avoid any visual
-                 gap between the end of Android's launch screen and the painting of
-                 Flutter's first frame. -->
-            <meta-data
-              android:name="io.flutter.embedding.android.SplashScreenDrawable"
-              android:resource="@drawable/launch_background"
-              />
+                android:name="io.flutter.embedding.android.NormalTheme"
+                android:resource="@style/NormalTheme" />
             <intent-filter>
-                <action android:name="android.intent.action.MAIN"/>
-                <category android:name="android.intent.category.LAUNCHER"/>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
         <!-- Don't delete the meta-data below.
@@ -37,5 +35,8 @@
         <meta-data
             android:name="flutterEmbedding"
             android:value="2" />
+
+
     </application>
+
 </manifest>
diff --git a/example/android/build.gradle b/example/android/build.gradle
index c505a86..bd16e88 100644
--- a/example/android/build.gradle
+++ b/example/android/build.gradle
@@ -1,20 +1,18 @@
-buildscript {
-    ext.kotlin_version = '1.3.50'
-    repositories {
-        google()
-        jcenter()
-    }
-
-    dependencies {
-        classpath 'com.android.tools.build:gradle:4.1.0'
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
-    }
-}
-
 allprojects {
     repositories {
         google()
-        jcenter()
+        mavenCentral()
+    }
+    subprojects {
+        afterEvaluate { project ->
+            if (project.hasProperty('android')) {
+                project.android {
+                    if (namespace == null) {
+                        namespace project.group
+                    }
+                }
+            }
+        }
     }
 }
 
@@ -26,6 +24,6 @@ subprojects {
     project.evaluationDependsOn(':app')
 }
 
-task clean(type: Delete) {
+tasks.register("clean", Delete) {
     delete rootProject.buildDir
 }
diff --git a/example/android/gradle/wrapper/gradle-wrapper.properties b/example/android/gradle/wrapper/gradle-wrapper.properties
index bc6a58a..fb5eb59 100644
--- a/example/android/gradle/wrapper/gradle-wrapper.properties
+++ b/example/android/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-all.zip
diff --git a/example/android/settings.gradle b/example/android/settings.gradle
index 44e62bc..0aedd55 100644
--- a/example/android/settings.gradle
+++ b/example/android/settings.gradle
@@ -1,11 +1,28 @@
-include ':app'
+pluginManagement {
+    def flutterSdkPath = {
+        def properties = new Properties()
+        file("local.properties").withInputStream { properties.load(it) }
+        def flutterSdkPath = properties.getProperty("flutter.sdk")
+        assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
+        return flutterSdkPath
+    }
+    settings.ext.flutterSdkPath = flutterSdkPath()
 
-def localPropertiesFile = new File(rootProject.projectDir, "local.properties")
-def properties = new Properties()
+    includeBuild("${settings.ext.flutterSdkPath}/packages/flutter_tools/gradle")
 
-assert localPropertiesFile.exists()
-localPropertiesFile.withReader("UTF-8") { reader -> properties.load(reader) }
+    repositories {
+        google()
+        mavenCentral()
+        gradlePluginPortal()
+    }
+}
 
-def flutterSdkPath = properties.getProperty("flutter.sdk")
-assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
-apply from: "$flutterSdkPath/packages/flutter_tools/gradle/app_plugin_loader.gradle"
+plugins {
+    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
+    id "com.android.application" version '8.3.0' apply false
+    id "org.jetbrains.kotlin.android" version "1.8.22" apply false
+    id "com.google.gms.google-services" version "4.4.0" apply false
+    id "com.google.firebase.crashlytics" version "2.9.9" apply false
+}
+
+include ":app"
diff --git a/example/lib/main.dart b/example/lib/main.dart
index 0d39e35..44b092d 100644
--- a/example/lib/main.dart
+++ b/example/lib/main.dart
@@ -36,15 +36,13 @@ class MyAppState extends State<MyApp> {
                   TextButton(
                     child: Text("Show Dialog 24 Hours"),
                     onPressed: () {
-                      showTimeRangePicker(
-                          _navigatorKey.currentState.overlay.context);
+                      showTimeRangePicker(_navigatorKey.currentState!.context);
                     },
                   ),
                   TextButton(
                     child: Text("Show Dialog 12 Hours"),
                     onPressed: () {
-                      showTimeRangePicker12Hour(
-                          _navigatorKey.currentState.overlay.context);
+                      showTimeRangePicker12Hour(_navigatorKey.currentState!.context);
                     },
                   ),
                 ],
@@ -70,13 +68,10 @@ class MyAppState extends State<MyApp> {
               editable: true,
               is24Format: true,
               disableTabInteraction: true,
-              iconCancel: Icon(Icons.cancel_presentation, size: 12),
-              iconNext: Icon(Icons.arrow_forward, size: 12),
-              iconBack: Icon(Icons.arrow_back, size: 12),
-              iconSelect: Icon(Icons.check, size: 12),
+
               separatorStyle: TextStyle(color: Colors.grey[900], fontSize: 30),
               onSelect: (from, to) {
-                _messangerKey.currentState.showSnackBar(
+                _messangerKey.currentState?.showSnackBar(
                     SnackBar(content: Text("From : $from, To : $to")));
                 Navigator.pop(context);
               },
@@ -108,13 +103,13 @@ class MyAppState extends State<MyApp> {
               iconNext: Icon(Icons.arrow_forward, size: 12),
               iconBack: Icon(Icons.arrow_back, size: 12),
               iconSelect: Icon(Icons.check, size: 12),
-              inactiveBgColor: Colors.grey[800],
+              inactiveBgColor: Colors.grey[800]!,
               timeContainerStyle: BoxDecoration(
                   color: Colors.grey[800],
                   borderRadius: BorderRadius.circular(7)),
               separatorStyle: TextStyle(color: Colors.grey[900], fontSize: 30),
               onSelect: (from, to) {
-                _messangerKey.currentState.showSnackBar(
+                _messangerKey.currentState?.showSnackBar(
                     SnackBar(content: Text("From : $from, To : $to")));
                 Navigator.pop(context);
               },
diff --git a/example/pubspec.lock b/example/pubspec.lock
index 471220c..66c2bd2 100644
--- a/example/pubspec.lock
+++ b/example/pubspec.lock
@@ -5,58 +5,58 @@ packages:
     dependency: transitive
     description:
       name: async
-      url: "https://pub.dartlang.org"
+      sha256: "947bfcf187f74dbc5e146c9eb9c0f10c9f8b30743e341481c1e2ed3ecc18c20c"
+      url: "https://pub.dev"
     source: hosted
-    version: "2.8.1"
+    version: "2.11.0"
   boolean_selector:
     dependency: transitive
     description:
       name: boolean_selector
-      url: "https://pub.dartlang.org"
+      sha256: "6cfb5af12253eaf2b368f07bacc5a80d1301a071c73360d746b7f2e32d762c66"
+      url: "https://pub.dev"
     source: hosted
-    version: "2.1.0"
+    version: "2.1.1"
   characters:
     dependency: transitive
     description:
       name: characters
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.1.0"
-  charcode:
-    dependency: transitive
-    description:
-      name: charcode
-      url: "https://pub.dartlang.org"
+      sha256: "04a925763edad70e8443c99234dc3328f442e811f1d8fd1a72f1c8ad0f69a605"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.3.1"
+    version: "1.3.0"
   clock:
     dependency: transitive
     description:
       name: clock
-      url: "https://pub.dartlang.org"
+      sha256: cb6d7f03e1de671e34607e909a7213e31d7752be4fb66a86d29fe1eb14bfb5cf
+      url: "https://pub.dev"
     source: hosted
-    version: "1.1.0"
+    version: "1.1.1"
   collection:
     dependency: transitive
     description:
       name: collection
-      url: "https://pub.dartlang.org"
+      sha256: ee67cb0715911d28db6bf4af1026078bd6f0128b07a5f66fb2ed94ec6783c09a
+      url: "https://pub.dev"
     source: hosted
-    version: "1.15.0"
+    version: "1.18.0"
   cupertino_icons:
     dependency: "direct main"
     description:
       name: cupertino_icons
-      url: "https://pub.dartlang.org"
+      sha256: ba631d1c7f7bef6b729a622b7b752645a2d076dba9976925b8f25725a30e1ee6
+      url: "https://pub.dev"
     source: hosted
-    version: "1.0.2"
+    version: "1.0.8"
   fake_async:
     dependency: transitive
     description:
       name: fake_async
-      url: "https://pub.dartlang.org"
+      sha256: "511392330127add0b769b75a987850d136345d9227c6b94c96a04cf4a391bf78"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.2.0"
+    version: "1.3.1"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -78,37 +78,74 @@ packages:
     dependency: transitive
     description:
       name: infinite_listview
-      url: "https://pub.dartlang.org"
+      sha256: f6062c1720eb59be553dfa6b89813d3e8dd2f054538445aaa5edaddfa5195ce6
+      url: "https://pub.dev"
     source: hosted
     version: "1.1.0"
+  leak_tracker:
+    dependency: transitive
+    description:
+      name: leak_tracker
+      sha256: "7f0df31977cb2c0b88585095d168e689669a2cc9b97c309665e3386f3e9d341a"
+      url: "https://pub.dev"
+    source: hosted
+    version: "10.0.4"
+  leak_tracker_flutter_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_flutter_testing
+      sha256: "06e98f569d004c1315b991ded39924b21af84cf14cc94791b8aea337d25b57f8"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.3"
+  leak_tracker_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_testing
+      sha256: "6ba465d5d76e67ddf503e1161d1f4a6bc42306f9d66ca1e8f079a47290fb06d3"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.1"
   matcher:
     dependency: transitive
     description:
       name: matcher
-      url: "https://pub.dartlang.org"
+      sha256: d2323aa2060500f906aa31a895b4030b6da3ebdcc5619d14ce1aada65cd161cb
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.12.16+1"
+  material_color_utilities:
+    dependency: transitive
+    description:
+      name: material_color_utilities
+      sha256: "0e0a020085b65b6083975e499759762399b4475f766c21668c4ecca34ea74e5a"
+      url: "https://pub.dev"
     source: hosted
-    version: "0.12.10"
+    version: "0.8.0"
   meta:
     dependency: transitive
     description:
       name: meta
-      url: "https://pub.dartlang.org"
+      sha256: "7687075e408b093f36e6bbf6c91878cc0d4cd10f409506f7bc996f68220b9136"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.7.0"
+    version: "1.12.0"
   numberpicker:
     dependency: transitive
     description:
       name: numberpicker
-      url: "https://pub.dartlang.org"
+      sha256: "4c129154944b0f6b133e693f8749c3f8bfb67c4d07ef9dcab48b595c22d1f156"
+      url: "https://pub.dev"
     source: hosted
-    version: "2.1.1"
+    version: "2.1.2"
   path:
     dependency: transitive
     description:
       name: path
-      url: "https://pub.dartlang.org"
+      sha256: "087ce49c3f0dc39180befefc60fdb4acd8f8620e5682fe2476afd0b3688bb4af"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.8.0"
+    version: "1.9.0"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -118,65 +155,74 @@ packages:
     dependency: transitive
     description:
       name: source_span
-      url: "https://pub.dartlang.org"
+      sha256: "53e943d4206a5e30df338fd4c6e7a077e02254531b138a15aec3bd143c1a8b3c"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.8.1"
+    version: "1.10.0"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
-      url: "https://pub.dartlang.org"
+      sha256: "73713990125a6d93122541237550ee3352a2d84baad52d375a4cad2eb9b7ce0b"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.10.0"
+    version: "1.11.1"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
-      url: "https://pub.dartlang.org"
+      sha256: ba2aa5d8cc609d96bbb2899c28934f9e1af5cddbd60a827822ea467161eb54e7
+      url: "https://pub.dev"
     source: hosted
-    version: "2.1.0"
+    version: "2.1.2"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
-      url: "https://pub.dartlang.org"
+      sha256: "556692adab6cfa87322a115640c11f13cb77b3f076ddcc5d6ae3c20242bedcde"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.1.0"
+    version: "1.2.0"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
-      url: "https://pub.dartlang.org"
+      sha256: a29248a84fbb7c79282b40b8c72a1209db169a2e0542bce341da992fe1bc7e84
+      url: "https://pub.dev"
     source: hosted
-    version: "1.2.0"
+    version: "1.2.1"
   test_api:
     dependency: transitive
     description:
       name: test_api
-      url: "https://pub.dartlang.org"
+      sha256: "9955ae474176f7ac8ee4e989dadfb411a58c30415bcfb648fa04b2b8a03afa7f"
+      url: "https://pub.dev"
     source: hosted
-    version: "0.4.2"
+    version: "0.7.0"
   toggle_switch:
     dependency: transitive
     description:
       name: toggle_switch
-      url: "https://pub.dartlang.org"
+      sha256: dca04512d7c23ed320d6c5ede1211a404f177d54d353bf785b07d15546a86ce5
+      url: "https://pub.dev"
     source: hosted
-    version: "0.1.9"
-  typed_data:
+    version: "2.3.0"
+  vector_math:
     dependency: transitive
     description:
-      name: typed_data
-      url: "https://pub.dartlang.org"
+      name: vector_math
+      sha256: "80b3257d1492ce4d091729e3a67a60407d227c27241d6927be0130c98e741803"
+      url: "https://pub.dev"
     source: hosted
-    version: "1.3.0"
-  vector_math:
+    version: "2.1.4"
+  vm_service:
     dependency: transitive
     description:
-      name: vector_math
-      url: "https://pub.dartlang.org"
+      name: vm_service
+      sha256: "3923c89304b715fb1eb6423f017651664a03bf5f4b29983627c4da791f74a4ec"
+      url: "https://pub.dev"
     source: hosted
-    version: "2.1.0"
+    version: "14.2.1"
 sdks:
-  dart: ">=2.12.0 <3.0.0"
-  flutter: ">=1.17.0"
+  dart: ">=3.3.0 <4.0.0"
+  flutter: ">=3.22.0"
diff --git a/example/pubspec.yaml b/example/pubspec.yaml
index 835af4a..081acd7 100644
--- a/example/pubspec.yaml
+++ b/example/pubspec.yaml
@@ -18,7 +18,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 version: 1.0.0+1
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: '>=3.1.0 <4.0.0'
 
 dependencies:
   flutter:
@@ -29,7 +29,7 @@ dependencies:
 
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
-  cupertino_icons: ^1.0.2
+  cupertino_icons: ^1.0.8
 
 dev_dependencies:
   flutter_test:
diff --git a/lib/flutter_time_range.dart b/lib/flutter_time_range.dart
index a4ba6df..dc4192c 100644
--- a/lib/flutter_time_range.dart
+++ b/lib/flutter_time_range.dart
@@ -63,6 +63,8 @@ class TimeRangePicker extends StatefulWidget {
   /// If true, user can change value of time manually with textfield
   final bool editable;
 
+  /// If true, user choose invalid time
+
   /// If false, AM-PM toggle will show.
   /// initial time is normal DateTime and will convert into 12 hours format.
   /// output time is normal TimeOfDay
@@ -120,10 +122,10 @@ class TimeRangePicker extends StatefulWidget {
 
   TimeRangePicker(
       {Key? key,
-      @required this.initialFromHour,
-      @required this.initialToHour,
-      @required this.initialFromMinutes,
-      @required this.initialToMinutes,
+      required this.initialFromHour,
+      required this.initialToHour,
+      required this.initialFromMinutes,
+      required this.initialToMinutes,
       this.onSelect,
       this.onCancel,
       this.tabFromText = "From",
@@ -164,6 +166,8 @@ class TimeRangePicker extends StatefulWidget {
 
 class _TimeRangePickerState extends State<TimeRangePicker>
     with SingleTickerProviderStateMixin {
+  bool isInvalidTime = false;
+
   late TabController _tabController;
   int _jamFrom = 0;
   int _menitFrom = 0;
@@ -297,14 +301,14 @@ class _TimeRangePickerState extends State<TimeRangePicker>
                                     minWidth: 90.0,
                                     minHeight: 30,
                                     cornerRadius: 20.0,
-                                    activeBgColor: widget.activeBgColor,
+                                    activeBgColor: [widget.activeBgColor],
                                     activeFgColor: widget.activeFgColor,
                                     inactiveBgColor: widget.inactiveBgColor,
                                     inactiveFgColor: widget.inactiveFgColor,
                                     labels: ['AM', 'PM'],
                                     initialLabelIndex: fromIndex,
                                     onToggle: (index) {
-                                      fromIndex = index;
+                                      fromIndex = index ?? 0;
                                     },
                                   ),
                                 ),
@@ -438,6 +442,12 @@ class _TimeRangePickerState extends State<TimeRangePicker>
                               ),
                             ],
                           ),
+                          SizedBox(height: 12),
+                          if (isInvalidTime)
+                            Text(
+                              'Invalid time values',
+                              style: TextStyle(color: Colors.red),
+                            )
                         ],
                       ),
                     ),
@@ -458,14 +468,14 @@ class _TimeRangePickerState extends State<TimeRangePicker>
                                     minWidth: 90.0,
                                     minHeight: 30,
                                     cornerRadius: 20.0,
-                                    activeBgColor: widget.activeBgColor,
+                                    activeBgColor: [widget.activeBgColor],
                                     activeFgColor: widget.activeFgColor,
                                     inactiveBgColor: widget.inactiveBgColor,
                                     inactiveFgColor: widget.inactiveFgColor,
                                     labels: ['AM', 'PM'],
                                     initialLabelIndex: toIndex,
                                     onToggle: (index) {
-                                      toIndex = index;
+                                      toIndex = index ?? 0;
                                     },
                                   ),
                                 ),
@@ -689,9 +699,18 @@ class _TimeRangePickerState extends State<TimeRangePicker>
                             : toIndex == 1
                                 ? (_jamTo + 12)
                                 : _jamTo;
-                        widget.onSelect?.call(
-                            TimeOfDay(hour: jamFr, minute: _menitFrom),
-                            TimeOfDay(hour: jamTo, minute: _menitTo));
+                        var from = TimeOfDay(hour: jamFr, minute: _menitFrom);
+                        var to = TimeOfDay(hour: jamTo, minute: _menitTo);
+                        if (to.hour < from.hour ||
+                            (to.hour == from.hour && to.minute < from.minute)) {
+                          print(isInvalidTime.toString());
+                          setState(() {
+                            isInvalidTime = true;
+                          });
+                          print(isInvalidTime.toString());
+                        } else {
+                          widget.onSelect?.call(from, to);
+                        }
                       }
                     },
                     child: Row(
diff --git a/pubspec.lock b/pubspec.lock
deleted file mode 100644
index d02b165..0000000
--- a/pubspec.lock
+++ /dev/null
@@ -1,168 +0,0 @@
-# Generated by pub
-# See https://dart.dev/tools/pub/glossary#lockfile
-packages:
-  async:
-    dependency: transitive
-    description:
-      name: async
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.8.1"
-  boolean_selector:
-    dependency: transitive
-    description:
-      name: boolean_selector
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.1.0"
-  characters:
-    dependency: transitive
-    description:
-      name: characters
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.1.0"
-  charcode:
-    dependency: transitive
-    description:
-      name: charcode
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.3.1"
-  clock:
-    dependency: transitive
-    description:
-      name: clock
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.1.0"
-  collection:
-    dependency: transitive
-    description:
-      name: collection
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.15.0"
-  fake_async:
-    dependency: transitive
-    description:
-      name: fake_async
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.2.0"
-  flutter:
-    dependency: "direct main"
-    description: flutter
-    source: sdk
-    version: "0.0.0"
-  flutter_test:
-    dependency: "direct dev"
-    description: flutter
-    source: sdk
-    version: "0.0.0"
-  infinite_listview:
-    dependency: transitive
-    description:
-      name: infinite_listview
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.1.0"
-  matcher:
-    dependency: transitive
-    description:
-      name: matcher
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "0.12.10"
-  meta:
-    dependency: transitive
-    description:
-      name: meta
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.7.0"
-  numberpicker:
-    dependency: "direct main"
-    description:
-      name: numberpicker
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.1.1"
-  path:
-    dependency: transitive
-    description:
-      name: path
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.8.0"
-  sky_engine:
-    dependency: transitive
-    description: flutter
-    source: sdk
-    version: "0.0.99"
-  source_span:
-    dependency: transitive
-    description:
-      name: source_span
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.8.1"
-  stack_trace:
-    dependency: transitive
-    description:
-      name: stack_trace
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.10.0"
-  stream_channel:
-    dependency: transitive
-    description:
-      name: stream_channel
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.1.0"
-  string_scanner:
-    dependency: transitive
-    description:
-      name: string_scanner
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.1.0"
-  term_glyph:
-    dependency: transitive
-    description:
-      name: term_glyph
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.2.0"
-  test_api:
-    dependency: transitive
-    description:
-      name: test_api
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "0.4.2"
-  toggle_switch:
-    dependency: "direct main"
-    description:
-      name: toggle_switch
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "0.1.9"
-  typed_data:
-    dependency: transitive
-    description:
-      name: typed_data
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.3.0"
-  vector_math:
-    dependency: transitive
-    description:
-      name: vector_math
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.1.0"
-sdks:
-  dart: ">=2.12.0 <3.0.0"
-  flutter: ">=1.17.0"
diff --git a/pubspec.yaml b/pubspec.yaml
index b50e9ee..45200a6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -4,14 +4,14 @@ version: 0.0.3
 homepage: https://github.com/alfanthariq/flutter_time_range
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
-  flutter: ">=1.17.0"
+  sdk: '>=3.1.0 <4.0.0'
+  flutter: ">=3.22.0"
 
 dependencies:
   flutter:
     sdk: flutter
-  numberpicker: ^2.1.1
-  toggle_switch: ^0.1.9
+  numberpicker: ^2.1.2
+  toggle_switch: ^2.3.0
 
 dev_dependencies:
   flutter_test: