How to customize the APK file name for product flavors?

I am customizing the name of the APK file of my Android application within the build.gradle script as follows:

android {
    defaultConfig {
        project.ext.set("archivesBaseName", "MyApplication");
    }
}

Now that I am using product flavors:

android {
    productFlavors {
        green {
            applicationId "com.example.myapplication.green"
        }

        blue {
            applicationId "com.example.myapplication.blue"
        }
    }
}

Is there a way to customize the name of each APK? I experimented with archiveBaseName and baseName without success. In the end I want to come up with the following files:

build/outputs/apk/Blue-debug-1.2.1.apk
build/outputs/apk/Blue-debug-unaligned.apk
build/outputs/apk/Blue-release-1.2.1.apk
build/outputs/apk/Blue-release-unaligned.apk
build/outputs/apk/Green-debug-1.2.1.apk
build/outputs/apk/Green-debug-unaligned.apk
build/outputs/apk/Green-release-1.2.1.apk
build/outputs/apk/Green-release-unaligned.apk

Try to put this in your android closure of build.gradle

buildTypes {
    debug {
        // debug buildType specific stuff
    }
    release {
        // release buildType specific stuff
    }
    applicationVariants.all { variant ->
        if (variant.buildType.name.equals("release") &&
            variant.productFlavors[0].name.equals("green") &&
            variant.zipAlign) {
                def apk = variant.outputFile;
                variant.outputFile = new File(apk.parentFile, "green.apk");
        } else if(variant.buildType.name.equals("release") &&
            variant.productFlavors[0].name.equals("blue") &&
            variant.zipAlign) {
                def apk = variant.outputFile;
                variant.outputFile = new File(apk.parentFile, "blue.apk");
        }
    }
}

Now the outputs should be like green.apk and blue.apk.

This will help you in 2022.

android {
    
//........
flavorDimensions "version"
productFlavors {
    Free {
        dimension "version"
        applicationId "com.exampleFree.app"
    }
    Paid {
        dimension "version"
        applicationId "com.examplePaid.app"
    }
}

applicationVariants.all { variant ->
    variant.outputs.all { output ->
        def appId = variant.applicationId// com.exampleFree.app OR com.examplePaid.app
        def versionName = variant.versionName
        def versionCode = variant.versionCode // e.g 1.0
        def flavorName = variant.flavorName // e. g. Free
        def buildType = variant.buildType.name // e. g. debug
        def variantName = variant.name // e. g. FreeDebug

        //customize your app name by using variables
        outputFileName = "${variantName}.apk"
    }
}}

Apk name FreeDebug.apk

Proof

For Android Gradle Plugin 0.13.+ you should use something like this:

android{
    buildTypes {
        applicationVariants.all { variant ->
            variant.outputs.each { output ->
                def apk = output.outputFile;
                def newName = "mysms-" + variant.baseName.replace("-release", "") + "-" + defaultConfig.versionName + ".apk";
                output.outputFile = new File(apk.parentFile, newName);
            }
        }
    }
}

For Android Studio 3.0 you must change from:

applicationVariants.all { variant ->
    variant.outputs.each { output ->
        output.outputFile = new File(output.outputFile.parent, "whatever" + ".apk")
    }
}

To:

android.applicationVariants.all { variant ->
        variant.outputs.all { 
            outputFileName = "whatever" + ".apk")
    }
}

I did it like this:

productFlavors {
        production {
            applicationId "com.example.production"
        }

        staging {
            applicationId "com.example.production.staging"

        }

        applicationVariants.all { variant ->
            variant.outputs.each { output ->
                if(variant.productFlavors[0].name.equals("staging")){
                    output.outputFile = new File(output.outputFile.parent,
                            output.outputFile.name.replace("app-staging-release",  "test"));

                }else{
                    output.outputFile = new File(output.outputFile.parent,
                            output.outputFile.name.replace("app-production-release",  "production"));
                }

            }
        }
    }