Today we are going to learn how we can generate an APK or AAB to distribute or publish our application to the app store using Flutter and VS Code.
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We have to create an application signing file with the following command:
keytool -genkey -v -keystore ~/upload-keystore.jks -keyalg RSA -keysize 2048 -validity 10000 -alias upload
Indicate the alias you need to specify. Remember to store it securely, as it will be requested.
In Windows, use this:
keytool -genkey -v -keystore upload-keystore.jks ^ -storetype JKS -keyalg RSA -keysize 2048 -validity 10000 ^ -alias upload
Now let’s create a file called key.properties in this path: [project]/android/key.properties
storePassword=<password-from-previous-step> keyPassword=<password-from-previous-step> keyAlias=upload storeFile=<keystore-file-location>
Specify the password you have created, the key alias, and where you save it.
And now we have to modify the app/build.gradle ([project]/android/app/build.gradle
)
Add the following before android { …
def keystoreProperties = new Properties() def keystorePropertiesFile = rootProject.file('key.properties') if (keystorePropertiesFile.exists()) { keystoreProperties.load(new FileInputStream(keystorePropertiesFile)) } android { ... }
Look for buildTypes and find:
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 } }
To replace it with:
signingConfigs { release { keyAlias keystoreProperties['keyAlias'] keyPassword keystoreProperties['keyPassword'] storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null storePassword keystoreProperties['storePassword'] } } buildTypes { release { signingConfig signingConfigs.release } }
Finally, execute the following command:
flutter clean
Then open the project and run this command if you want to build an AAB:
flutter build appbundle
Or this if you want to build an APK:
flutter build apk
Remember to increase the corresponding version number within local.properties
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Although this file is overwritten, so let’s create a new file named prod.properties where we will add the following:
flutter.versionName=1.0.0 flutter.versionCode=1
And we have to link it in our app/build.gradle by changing this content:
def localProperties = new Properties() def localPropertiesFile = rootProject.file('local.properties') if (localPropertiesFile.exists()) { localPropertiesFile.withReader('UTF-8') { reader -> localProperties.load(reader) } } def flutterVersionCode = localProperties.getProperty('flutter.versionCode') if (flutterVersionCode == null) { flutterVersionCode = '1' } def flutterVersionName = localProperties.getProperty('flutter.versionName') if (flutterVersionName == null) { flutterVersionName = '1.0' }
With this:
def localProperties = new Properties() def localPropertiesFile = rootProject.file('prod.properties')
I’ve only changed local.properties to prod.properties
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