Migrating Android Build Configuration From Groovy to Kotlin

Android app development has evolved over the years, and so has the tooling around it. Gradle, the build automation system for Android projects, has seen significant improvements, and one notable change is the shift from Groovy to Kotlin for building configuration files. This migration brings various benefits, including improved type safety, better IDE support, and enhanced code readability. In this blog post, we’ll explore the process of migrating your Android build configuration from Groovy to Kotlin.

Why is Migration required?

While Groovy has served as the primary language for Gradle build scripts in Android projects, Kotlin has become the preferred choice due to its concise Syntax, null safety, and seamless integration with modern IDEs. Migrating to Kotlin not only aligns your build configuration with the latest industry trends but also opens the door to leveraging Kotlin-specific features.

Step 1: Update the Gradle wrapper

Before diving into the build script migration, it’s essential to update the Gradle Wrapper to the latest version that supports Kotlin DSL. Typically, this means using Android Gradle Plugin 4.0.0 or later. Update your project’s Gradle files to reflect this version requirement.

// build.gradle (project level)
buildscript {
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:4.0.0'
    }
}

Open the gradle-wrapper.properties file and set the distributionUrl to a version that includes Kotlin DSL support.

distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-all.zip

Step 2: Convert the build script

Now, let’s start migrating the actual build script. Follow these steps

a. Backup Your Project
Before making any changes, create a backup of your project to avoid accidental data loss.

b. Create a New Kotlin Build Script
Create a new Kotlin build script file, typically named build.gradle.kts, in the module or project directory.

c. Copy Existing Configuration:

Copy the content of your existing Groovy build script (build.gradle) to the newly created Kotlin script (build.gradle.kts). And start converting your Groovy-based build scripts to Kotlin DSL.

Module-level build script:

// Groovy
android {
    compileSdkVersion 30
    defaultConfig {
        applicationId "com.example.myapp"
        minSdkVersion 16
        targetSdkVersion 30
    }
}

// Kotlin DSL
android {
    compileSdkVersion(30)
    defaultConfig {
        applicationId = "com.example.myapp"
        minSdkVersion(16)
        targetSdkVersion(30)
    }
}

Project-level build script

// build.gradle.kts (project level)
plugins {
    kotlin("android") version "1.4.32"
    kotlin("android.extensions") version "1.1.0"
}

android {
    // ... (existing configuration)
}

dependencies {
    // ... (existing dependencies)
}

d. Adjust Syntax:

Update the Syntax according to Kotlin DSL. For instance, use val for defining constants. While converting from Groovy to Kotlin DSL, you may encounter syntax differences. Pay attention to the following expected changes:

• Property Access Syntax:
• Groovy: ‘android.defaultConfig.applicationId’
• Kotlin: ‘android.defaultConfig.applicationId’
• Closure Syntax:
  Groovy

android {
    buildTypes {
        release {
            // ...
        }
    }
}

Kotlin

android {
    buildTypes {
        getByName("release") {
            // ...
        }
    }
}

e. Leverage Kotlin Features:

Take advantage of Kotlin features such as extension functions, lambdas, and named parameters to enhance the readability and maintainability of your build script.

android {
    // Existing configuration...

    buildTypes {
        getByName("release") {
            isMinifyEnabled = false
            proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
        }
    }
}

f. Verify and Test

After migrating, carefully review the new Kotlin build script for any errors or inconsistencies. Test your project to ensure that the migration hasn’t introduced any issues.

Migrating your Android build configuration from Groovy to Kotlin

Take a proactive step towards adopting modern development practices.

The benefits of Kotlin DSL, such as improved type safety and enhanced readability, make the migration worthwhile. By following the outlined steps, you can seamlessly transition to Kotlin and position your Android project for future advancements in the Android development ecosystem.

Crafting Your Path to Future-Ready Android Development

At Payoda, we understand that the key to future-proofing your Android projects lies in embracing innovation. That’s why our meticulously outlined steps ensure a seamless transition to Kotlin, positioning your Android project for the exciting advancements in the Android development ecosystem.

Future-Ready Frameworks: Embrace the future with open arms. By migrating to Kotlin, you’re not just keeping up; you’re setting the stage for your Android project to thrive in the ever-evolving tech landscape.

Innovation is Our Currency

Choose Payoda as more than just a service provider; choose us as your innovation partner. In the world of Android development, innovation is the currency that propels you forward. Join hands with us, and let’s sculpt a future where your Android projects not only survive but thrive.

Take the leap into tomorrow with Payoda. Your Android projects deserve nothing less than a future-ready transformation. Ready to redefine your Android development journey? Let’s innovate together!

Authored by: Nanthakumar R