Made otp field text single digit and override text behaviour added

example/android/app/build.gradle

@@ -26,7 +26,7 @@ apply plugin: 'kotlin-android'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion 31
 
     sourceSets {
         main.java.srcDirs += 'src/main/kotlin'
@@ -40,7 +40,7 @@ android {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
         applicationId "com.example.example"
         minSdkVersion 16
-        targetSdkVersion 28
+        targetSdkVersion 31
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"

example/android/app/src/main/AndroidManifest.xml

@@ -6,12 +6,12 @@
          additional functionality it is fine to subclass or reimplement
          FlutterApplication and put your custom class here. -->
     <application
-        android:name="io.flutter.app.FlutterApplication"
         android:label="example"
         android:icon="@mipmap/ic_launcher">
         <activity
             android:name=".MainActivity"
             android:launchMode="singleTop"
+            android:exported="true"
             android:theme="@style/LaunchTheme"
             android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
             android:hardwareAccelerated="true"

example/android/build.gradle

@@ -1,12 +1,12 @@
 buildscript {
-    ext.kotlin_version = '1.3.50'
+    ext.kotlin_version = '1.6.10'
     repositories {
         google()
         jcenter()
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.5.0'
+        classpath 'com.android.tools.build:gradle:4.2.2'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }

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-5.6.2-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-all.zip

example/lib/main.dart

@@ -38,9 +38,6 @@ class _MyHomePageState extends State<MyHomePage> {
         onPressed: () {
           print("Floating button was pressed.");
           otpController.clear();
-          // otpController.set(['2', '3', '5', '5', '7']);
-          // otpController.setValue('3', 0);
-          // otpController.setFocus(1);
         },
       ),
       body: Center(

example/pubspec.lock

@@ -42,7 +42,7 @@ packages:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0"
+    version: "1.16.0"
   cupertino_icons:
     dependency: "direct main"
     description:
@@ -56,7 +56,7 @@ packages:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0"
+    version: "1.3.0"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -80,7 +80,7 @@ packages:
       name: material_color_utilities
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.1.3"
+    version: "0.1.4"
   meta:
     dependency: transitive
     description:
@@ -94,14 +94,14 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "1.1.2"
+    version: "1.1.3"
   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
@@ -113,7 +113,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.1"
+    version: "1.8.2"
   stack_trace:
     dependency: transitive
     description:
@@ -148,20 +148,13 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.4.8"
-  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: "2.1.1"
+    version: "2.1.2"
 sdks:
-  dart: ">=2.14.0 <3.0.0"
+  dart: ">=2.17.0-0 <3.0.0"

lib/otp_field.dart

@@ -178,15 +178,21 @@ class _OTPTextFieldState extends State<OTPTextField> {
             right: isLast ? 0 : widget.spaceBetween,
           ),
       child: TextField(
+        onTap: () {
+          _textControllers[index]!.selection = TextSelection.fromPosition(
+              TextPosition(offset: _textControllers[index]!.text.length));
+        },
         controller: _textControllers[index],
         keyboardType: widget.keyboardType,
         textCapitalization: widget.textCapitalization,
         textAlign: TextAlign.center,
         style: widget.style,
         inputFormatters: widget.inputFormatter,
-        maxLength: 1,
+        //maxLength: 1,
+        maxLength: 2,
         focusNode: _focusNodes[index],
         obscureText: widget.obscureText,
+        showCursor: false,
         decoration: InputDecoration(
           isDense: widget.isDense,
           filled: true,
@@ -205,8 +211,25 @@ class _OTPTextFieldState extends State<OTPTextField> {
         ),
         onChanged: (String str) {
           if (str.length > 1) {
-            _handlePaste(str);
-            return;
+            if (str.length == widget.length && index == widget.length - 1) {
+              print('Handling Paste');
+              _handlePaste(str);
+              return;
+            } else {
+              // User modified same position
+              if (_pin.length >= index + 1) {
+                // remove previously entered digit
+                str = str.replaceFirst(_pin[index], '');
+              } else {
+                // Take the last entered digit as otp entry
+                int len = str.length;
+                str = str[len - 1];
+              }
+              // Update the current pin
+              setState(() {
+                _textControllers[index]!.text = str;
+              });
+            }
           }
 
           // Check if the current value at this position is empty
@@ -235,7 +258,8 @@ class _OTPTextFieldState extends State<OTPTextField> {
           // Call the `onCompleted` callback function provided
           if (!_pin.contains(null) &&
               !_pin.contains('') &&
-              currentPin.length == widget.length) {
+              currentPin.length == widget.length &&
+              index + 1 == widget.length) { // Only call this when user is on last digit
             widget.onCompleted?.call(currentPin);
           }
 

pubspec.lock

@@ -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
@@ -73,7 +73,7 @@ packages:
       name: material_color_utilities
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.1.3"
+    version: "0.1.4"
   meta:
     dependency: transitive
     description:
@@ -87,7 +87,7 @@ packages:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -99,7 +99,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.1"
+    version: "1.8.2"
   stack_trace:
     dependency: transitive
     description:
@@ -134,20 +134,13 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.4.8"
-  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: "2.1.1"
+    version: "2.1.2"
 sdks:
-  dart: ">=2.14.0 <3.0.0"
+  dart: ">=2.17.0-0 <3.0.0"