Android

The App ID, App Name, icons and signing should be set in the android config files.

Table of contents

1. App ID
2. App Name
3. App Icons
4. App Signing

App ID

Update the application id in android/app/build.gradle:

applicationId "com.mycompany.myapp"

Note: versionCode and versionName can be ignored. These are updated automatically by Fledge.

App Name

Update the app name in android/app/src/main/AndroidManifest.xml

android:label="<MyUniqueAppName>"

This is the name that appears below the icon on the app.

App Icons

The set of icons, required for an Android app, can be generated in a number of different ways. For one way to generate a complete set of icons from a single image, see https://makeappicon.com. This will generate an set if icons for Android. Overwrite the existing catalog using:

cp -r <location of downloaded icons>/android/mipmap* android/app/src/main/res/

See also: https://romannurik.github.io/AndroidAssetStudio/icons-launcher.html

App Signing

An android app requires signing using a private key that you generate yourself. It is important that you manage this private key carefully. For example, never check it into your repo.

To learn more about app signing see: https://developer.android.com/studio/publish/app-signing.

Some of the following steps were taken from:
https://flutter.dev/docs/deployment/android

Setting-up your app for android signing:

1. Generate a new keystore for your app. You will be asked for a store password and key password, remember them for next step:

    keytool -genkey -v -keystore android/key.jks -keyalg RSA -keysize 2048 -validity 10000 -alias key
    keytool -importkeystore -srckeystore android/key.jks -destkeystore android/key.jks -deststoretype pkcs12
   

2. Create the android/key.properties:

    storePassword=<store password>
    keyPassword=<key password>
    keyAlias=key
    storeFile=../key.jks
   

3. Enable android release builds in android/app/build.gradle:

   Replace:

    apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
       
    android {
   

   with

    apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
       
    def keystoreProperties = new Properties()
    def keystorePropertiesFile = rootProject.file('key.properties')
    if (keystorePropertiesFile.exists()) {
        keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
    }
       
    android {
   

   and replace:

        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
            }
            profile {
                matchingFallbacks = ['debug', 'release']
            }
        }
   

   with:

        signingConfigs {
            release {
                keyAlias keystoreProperties['keyAlias']
                keyPassword keystoreProperties['keyPassword']
                storeFile file(keystoreProperties['storeFile'])
                storePassword keystoreProperties['storePassword']
            }
        }
        buildTypes {
            release {
                signingConfig signingConfigs.release
            }
        }
   

4. Confirm you can build a signed release without error

    flutter build apk --release
   

   or

    flutter build appbundle --release
   

5. Encrypt both files with:

    KEY_PASSWORD=<my secret key password>
    openssl enc -aes-256-cbc -salt -in android/key.jks -out android/key.jks.enc -k $KEY_PASSWORD
    openssl enc -aes-256-cbc -salt -in android/key.properties -out android/key.properties.enc -k $KEY_PASSWORD
   

   Remember value of KEY_PASSWORD for use in build server setup.

6. Add the following to your .gitignore:

   **/android/key.properties
   **/android/key.jks
   

7. Commit key.jks.enc and key.properties.enc and android/app/build.gradle.