Gradle and Eclipse

You just generated your libgdx project, now it's time to start developing its guts in Eclipse!

Before you can import your project into Eclipse, make sure you setup your development environment!

Importing Your Project

Go to File -> Import -> Gradle -> Gradle Project, click Browse and navigate to the root folder of your project, then click Build Model. After a while, you'll see a root project and subprojects (android, core, desktop, html, ios). Select all the projects and click Finish. Note that this process can take a minute or two the first time you do it, as Gradle and some dependencies will be downloaded in the background.

Common Problems

Your Eclipse workspace folder must not be the same as your project's root folder (see this issue).

If you run into problems due to a missing validation-api:1.0.0.GA artifact, delete your Maven cache at C:\Users\username\.m2 or /Users/username/.m2 or /home/username/.m2.

When importing your first project you receive the error: com/github/jtakakura/gradle/plugins/robovm/RoboVMPlugin : Unsupported major.minor version 51.0 Make sure you are running Oracle's JDK version 7 or above.

Running Your Project

• Desktop: Right click the desktop project, Run As -> Java Application. Select the desktop starter class (e.g. DesktopLauncher.java).
• Android: make sure you have a device connected and that it shows up in DDMS (see Android Developer Guide). Right click your Android project, Run As -> Android Application.
• BlackBerry 10: You need have the BlackBerry Eclipse plugin installed (http://developer.blackberry.com/android/documentation/install_bb_plugin_adt.html). You also need a BlackBerry ID signing token, which you can get by following these steps. Right click the project and under BlackBerry Tools -> Start ADB Proxy Manager. In there you can click the play button on your device. After it says "Running at port #49570" the device will show up in the ADB devices list and you can run it just like a real Android device.
• iOS RoboVM: Before you can run/debug on iOS, make sure you have the RoboVM Eclipse plugin installed. Once the plugin is installed, right click the robovm project, Run As -> iOS Device App to run on a connected device, or Run As -> iOS Simulator App to run on the iOS simulator. If you run on a device, you need to provision it to be able to deploy to it!
• HTML5: Right click the html project, Run As -> External Tools Configuration. Create a new configuration by double clicking the Program entry in the left sidebar. Give the configuration a name, e.g. GWT SuperDev. Set the location field to the gradlew.bat (Windows) or gradlew (Linux, Mac) file. Set the working directory to the root folder of your project. Specify html:superDev as the Argument. Press 'Apply', then 'Run'. Wait until you see the message The code server is ready. in the console view, then open the URL http://localhost:8080/html. You can leave the server running. If you change code or assets, simply click the SuperDev Refresh button in the browser. This will recompile your app and reload the site.

Once this bug in the Gradle tooling API is fixed, we can simplify running the HTML5 by using the Gradle integration. At the moment, the Gradle process will run forever even if canceled.

Debugging Your Project

Follow the steps for running the project, but instead of launching via Run as, launch your configuration via Debug as. Debugging of the html build can be done in the browser as follows:

Run the superDev run configuration as before. Go to http://localhost:8080/html, click the SuperDev Refreshbutton. In Chrome, press F12 to bring up the developer tools, go to the sources tab and find the Java file you want to debug. Set breakpoints, step and inspect variables using the power of source maps! Click the SuperDev Refresh button in case you changed code or assets (leave the server process running!).

Packaging Your Project

It's easiest to package your application from the command line, or using the Gradle tasks from within Eclipse. To see the relevant Gradle tasks, check the Gradle command line documentation.