Build your Android App with Gradle

1. Build your Android App with Gradle Android new build system

2. Agenda • What is Gradle • Getting started with gradle • Use cases • Q&A

3. Download Meetup Sample Code • http://goo.gl/qoXAfa

4. What is gradle • Gradle is a JVM based project build automation tool that builds upon the concepts of Apache Ant and Apache Maven and introduces a Groovy baseddomain-specific-language (DSL) instead of the more traditional XML form of declaring the project configuration.

5. Installation • Download the latest android plugin supported Gradle version • Extract the downloaded zip “gradle-1.10-all.zip” to any directory • Configure the GRADLE_HOME environment variable • set GRADLE_HOME=<installed directoy>\gradle-1.10 • set PATH=%PATH%\%GRADLE_HOME%\bin • C:\> gradle

6. Gradle Task • C:\> gradle tasks • Applying the plugin’s to the build file will automatically add set of build task to run • assembleThe task to assemble the output(s) of the project • checkThe task to run all the checks. • buildThis task does both assemble and check • cleanThis task cleans the output of the project

7. Build File Skeleton buildscript { repositories { mavenCentral() } dependencies { classpath 'com.android.tools.build:gradle:0.8.+' } } apply plugin: 'android' android { buildToolsVersion "19.0.1" compileSdkVersion 19 }

8. Gradle Wrapper task wrapper(type: Wrapper) { gradleVersion= '1.10‘ } • C:\> gradle wrapper / └── gradlew └── gradlew.bat └── gradle └── wrapper └── gradle-wrapper.jar └── gradle-wrapper.properties

9. Convention Over Configuration src └── main l └── java l └── instrumentTest └── java sourceSets { main{ manifest.srcFile'AndroidManifest.xml' java.srcDirs= ['src'] resources.srcDirs= ['src'] res.srcDirs= ['res'] assets.srcDirs= ['assets'] } instrumentTest.setRoot('tests') }

10. Usecase : 1 I have project with multiple library projects, one of which is required to be shared with one of my colleague who's working in a another project.

11. Dependency Management • dependencies DSL element is part of the standard Gradle • Can add dependencies on local and remote libraries • To add a dependency have to provide library on the compile configuration under dependencies DSL • Everything added to the compileconfiguration get packaged in to the final APK • Gradle will follow all dependencies transitively

12. Dependencies On Multiple Projects • Each projects will have its own build.gradle declaring how it gets built • There will be a file calledsettings.gradle at the root, which define which folder is a Gradle project • If there are more than one library, importing order should be considered on dependencies on each other

13. Publish Library To Artifact Repo • Publish artifacts to local artifact repository • Proper release and snapshot release management Maven Central

14. Usecase :2 • I want to make a digitally signed and secured release version of my app

15. Build types • This is achieved by buildTypesDSL • By default, the android plugin automatically sets up the project to build both a debug and a release version of the application • Difference is that the ability to enable debug and how the APK is signed • It allows to customize both debug and release versions, as well as creating other build types

16. Build Types… • Build Types can contribute to the build with code and resources. • For each Build Type, a new matching sourceSetis created, under src directory src/<buildtypename>/ • This means the Build Type names cannot be main or instrumentTest

17. Signing APK • Android system will not install or run an application that is not signed appropriately. • To sign an APK have to make use of signingConfigsDSL

18. Obfuscating • Tool ProGuard is used automatically to obfuscate the APK • It will rename classes, fields, and methods with semantically obscure names to make it difficult to reverse engineer. • Android plugin support proguard version is 4.10 • ProGuardwill shrinks, optimizes, and remove unused code which will result smaller APK

19. Usecase : 3 • I want to make a free version of my application with less features and commercial version with all features.

20. Build Variants • Different versions of the same application or Same application packaged differently or combination of both. • Have to occupy productFlavors DSL • Build Type + Product Flavor = Build Variant • Product flavor will generate APK’s for all possible combinations of Build Types and Product Flavors

21. Usecase: 4 I want to unit test my project with a testing framework,

22. Testing • No need to have a separate test project any more it is integrated to the application project • Default location for the instrument test cases are located in src/instrumentTest • Test APK is built to test the app under test using the Android instrumentation framework • No need to have a AndroidManifest.xml for the app, cause it will get generated automatically • Test app manifest is automatically get filled with the package name and the instrument test runner

23. Usecase: 5 • I want to measure the quality of my source code continuously with some quality tools by Integrate it with a Continuous Integration System

24. Q&A

25. Thank you