'Flutter Release APK for playstore

I am trying to generate a build apk, but getting following error. this is compatible with flutter version 2.8.1

Getting following error while run flutter build apk

/home/dell/snap/flutter/common/flutter/bin/flutter --no-color build apk

Building without sound null safety
For more information see https://dart.dev/null-safety/unsound-null-safety

Running Gradle task 'assembleRelease'...                        
Warning: Mapping new ns http://schemas.android.com/repository/android/common/02 to old ns http://schemas.android.com/repository/android/common/01
Warning: Mapping new ns http://schemas.android.com/repository/android/generic/02 to old ns http://schemas.android.com/repository/android/generic/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/addon2/02 to old ns http://schemas.android.com/sdk/android/repo/addon2/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/repository2/02 to old ns http://schemas.android.com/sdk/android/repo/repository2/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/sys-img2/02 to old ns http://schemas.android.com/sdk/android/repo/sys-img2/01

Note: /home/dell/.pub-cache/hosted/pub.dartlang.org/geocoding-2.0.2/android/src/main/java/com/baseflow/geocoding/GeocodingPlugin.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: /home/dell/.pub-cache/hosted/pub.dartlang.org/google_maps_flutter-2.1.1/android/src/main/java/io/flutter/plugins/googlemaps/Convert.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: /home/dell/.pub-cache/hosted/pub.dartlang.org/path_provider_android-2.0.11/android/src/main/java/io/flutter/plugins/pathprovider/PathProviderPlugin.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
e: /var/projects/app/freshooo/android/app/src/main/kotlin/com/u6amtech/flutter_grocery/Application.kt: (11, 51): Unresolved reference: setPluginRegistrant
e: /var/projects/app/freshooo/android/app/src/main/kotlin/com/u6amtech/flutter_grocery/FirebaseCloudMessagingPluginRegistrant.kt: (15, 44): Unresolved reference: registerWith

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:compileReleaseKotlin'.
> Compilation error. See log for more details

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 2m 6s
Running Gradle task 'assembleRelease'...                          126.8s
Gradle task assembleRelease failed with exit code 1

pubspec.yaml

name: flutter_grocery
description: A new Flutter application.
publish_to: 'none' # Remove this line if you wish to publish to pub.dev

version: 1.1.0+2

environment:
  sdk: ">=2.7.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter
  flutter_localizations:
    sdk: flutter

  cupertino_icons: ^1.0.2
  get_it: ^6.0.0
  provider: ^5.0.0
  http: ^0.13.1
  freezed: ^0.14.1
  shared_preferences: ^2.0.5
  photo_view: ^0.12.0
  dio: ^4.0.0-prev2
  image_picker: ^0.7.3
  pin_code_fields: ^7.0.0
  google_maps_flutter_web: ^0.3.0
  google_maps_flutter: ^2.0.3
  flutter_google_places: ^0.3.0
  geocoding: ^2.0.0
  geolocator: ^7.0.1
  shimmer_animation: ^2.0.0
  url_launcher: ^6.0.2
  webview_flutter: ^2.0.2
  firebase_core: ^1.7.0
  firebase_messaging: ^10.0.8
  flutter_local_notifications: ^8.2.0
  path_provider: ^2.0.1
  flutter_html: ^2.0.0-nullsafety.0
  connectivity: ^3.0.2
  carousel_slider: ^4.0.0-nullsafety.0
  fluro: ^2.0.3
  url_strategy: ^0.2.0
  universal_html: ^2.0.8
  universal_ui: ^0.0.8
  flutter_widget_from_html_core: ^0.6.1
  phone_number: ^0.11.0+2
  country_code_picker: ^2.0.2
  flutter_typeahead: ^3.1.3

dev_dependencies:
  flutter_test:
    sdk: flutter

flutter:
  uses-material-design: true

  assets:
    - assets/image/
    - assets/language/

  fonts:
    - family: Poppins
      fonts:
        - asset: assets/font/Poppins-Light.ttf
          weight: 300
        - asset: assets/font/Poppins-Regular.ttf
          weight: 400
        - asset: assets/font/Poppins-Medium.ttf
          weight: 500
        - asset: assets/font/Poppins-SemiBold.ttf
          weight: 600
        - asset: assets/font/Poppins-Bold.ttf
          weight: 700

app/build.gradle

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new FileNotFoundException("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'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
apply plugin: 'com.google.gms.google-services'

def keystoreProperties = new Properties()
def keystorePropertiesFile = rootProject.file('key.properties')
if (keystorePropertiesFile.exists()) {
    keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
}

android {
    compileSdkVersion 30

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    lintOptions {
        disable 'InvalidPackage'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.fresh.grocery"
        minSdkVersion 21
        targetSdkVersion 30
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        multiDexEnabled true
    }

    signingConfigs {
        release {
            keyAlias keystoreProperties['keyAlias']
            keyPassword keystoreProperties['keyPassword']
            storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
            storePassword keystoreProperties['storePassword']
        }
    }

    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.debug
        }
    }
}

flutter {
    source '../..'
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation "com.google.firebase:firebase-messaging:21.0.1"
    implementation 'com.android.support:multidex:1.0.3'
}

android/build.gradle

buildscript {
    ext.kotlin_version = '1.5.20'
    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.4'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'com.google.gms:google-services:4.3.5'
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }

    tasks.withType(JavaCompile) {
        options.compilerArgs << '-Xlint:-options'
    }
}

rootProject.buildDir = '../build'
subprojects {
    project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
    project.evaluationDependsOn(':app')
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

gradle-wrapper.properties

#Fri Jun 23 08:50:38 CEST 2017
distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https://services.gradle.org/distributions/gradle-6.3-all.zip

key.properties

storePassword=123456
keyPassword=123456
keyAlias=upload
storeFile=~/home/dell/upload-keystore.jks

Project Setting

Solution 1:^[1]

Please don't show confidential code like your package name, key.properties file kindly edit and remove those to protect your app from malicious itentions.

Since your flutter version is 2.8.1 but your dart sdk in pubspec.yaml is sdk: ">=2.7.0 <3.0.0" it requires to enable null-safety for your project just change the 2.7.0 to 2.12.0 or above, and also do require changes for flutter null safety for more details check out this https://dart.dev/null-safety/unsound-null-safety

You maybe getting this error as some of the packages you used in your project use null-safety so migrate your app to null-safety.

You can check this for more details about generating production apps https://docs.flutter.dev/deployment/android

you can also use this code to generate a obfuscated apk

flutter build apk --release --obfuscate --split-debug-info={directory}

similarly for appbundle:

flutter build appbundle --release --obfuscate --split-debug-info={directory}

Solution 2:^[2]

For release playstore build change

this in app/build.gradle

    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.debug
        }
    }

    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
        }
    }

Solution 3:^[3]

Did you register your Application class in the Manifest file?

like this :

<application
        android:name=".Application"
        android:label="app_name"
        android:icon="@mipmap/ic_launcher"/>

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1	Harsh Kothari
Solution 2	Sahil Hariyani
Solution 3	Hardik Mehta

'Flutter Release APK for playstore

Solution 1:[1]

Solution 2:[2]

Solution 3:[3]

Sources

Related Questions

Solution 1:^[1]

Solution 2:^[2]

Solution 3:^[3]