Next up, you need to import your project into your IDE.

Importing the Project

If you have just generated the project in gdx-liftoff, you may click the option “Open in IntelliJ Idea” to get started right away. Otherwise, continue with the following steps:

In IntelliJ IDEA or Android Studio, you can choose to open the build.gradle file and select “Open as Project” to get started.

In Eclipse, choose File -> Import... -> Gradle -> Existing Gradle Project (make sure that your freshly generated project is not located inside of your workspace).

In NetBeans it is File -> Open Project.
You may need to refresh the Gradle project after the initial import if some dependencies weren’t downloaded yet.

In IntelliJ IDEA/Android Studio, the Reimport all Gradle projects button is a pair of circling arrows at the top left in the Gradle tool window, which can be opened with View -> Tool Windows -> Gradle.

In Eclipse right-click on your project Gradle -> Refresh Gradle Project.

Getting it Running

If you want to execute your freshly imported project, you have to follow different steps, depending on your IDE and the platform you are targeting.

Desktop

In IDEA/Android Studio:

Extend the Gradle tab on the right side of your window.
Expand the tasks of your project and then select: lwjgl3 -> Tasks -> application -> run:

In Android Studio 4.2, tasks are no longer shown by default. Go to Settings -> Experimental and check Configure all Gradle tasks during Gradle Sync. Then sync the project via File -> Sync Project with Gradle Files:

Alternatively, you can create a run configuration:

Right-click your Lwjgl3Launcher class
Select ‘Run Lwjgl3Launcher.main()’. This should fail with missing assets, because we need to hook up the assets folder first:
Open up Run Configurations:
Edit the Run Configuration that was just created by running the lwjgl3 project and set the working directory to point to your assets folder:

On macOS, LWJGL3 projects require one extra step: Either, in your Run Configuration, set the VM Options to -XstartOnFirstThread. Or, add the following experimental code snippet to your main() method: if (SharedLibraryLoader.isMac) Configuration.GLFW_LIBRARY_NAME.set("glfw_async"); Additional information on this can be found here.
Run your application using the run button

In Eclipse:

Double click the projectname-lwjgl3 -> application -> run task under Gradle Tasks.

If the window is not visible, show it under Window -> Show View -> Other -> Gradle -> Gradle Tasks

Alternatively, you can create a run configuration:

Right-click your lwjgl3 project -> Run as -> Run Configurations…
On the right side, select Java Application:
At the top left, click the icon to create a new run configuration:
As Main class select your Lwjgl3Launcher class
After that, click on the Arguments tab
At the bottom, under ‘Working directory’ select ‘Other’ -> Workspace…

On macOS, LWJGL3 projects require one extra step: Either, in your Run Configuration, set the VM Options to -XstartOnFirstThread. Or, add the following experimental code snippet to your main() method: if (SharedLibraryLoader.isMac) Configuration.GLFW_LIBRARY_NAME.set("glfw_async"); Additional information on this can be found here.
Then select your asset folder located in assets

In NetBeans:

Right-click the lwjgl3 project -> Run

Android

IDEA/Android Studio: Right-click AndroidLauncher -> Run AndroidLauncher
Eclipse: Right-click Android project -> Run As -> AndroidApplication
NetBeans: Right-click Android project -> Run As -> AndroidApplication

iOS

In IDEA/Android Studio

Open Run/Debug Configurations
Create a new run configuration for a RoboVM iOS application
Select the provisioning profile and simulator/device target

Note: arm64 simulators are not working by default. Either use x86_64 or use the MetalANGLE RoboVM backend instead (“com.badlogicgames.gdx:gdx-backend-robovm-metalangle:$gdxVersion”)
Run the created run configuration

For more information on using and configuring the RoboVM IntelliJ IDEA plugin please see the documentation.

In Eclipse

Right-click the iOS RoboVM project > Run As > RoboVM runner of your choice

For more information on using and configuring the RoboVM IntelliJ IDEA plugin please see the documentation.

HTML

HTML is best suited to be run on command line. You are welcome to manually setup GWT in the IDE of your choice if you are familiar with it, but the recommended way is to drop down to terminal or command prompt.

The HTML target can be run in Super Dev mode, which allows you to recompile on the fly, and debug your application in browser.

To do so, open up your favourite shell or terminal, change directory to the project directory and invoke the respective gradle task:

./gradlew html:superDev

On Unix: If you get a permission denied error, set the execution flag on the gradlew file: chmod +x gradlew

You should see lots of text wizzing by, and if all goes well you should see the following line at the end:

You can then go to http://localhost:8080/index.html, to see your application running, with a recompile button.

For further info on configuring and debugging with SuperDev check the GWT documentation.

Command Line

All the targets can be run and deployed to via the command line interface.

Desktop:

./gradlew lwjgl3:run

Android:

./gradlew android:installDebug android:run

The ANDROID_HOME environment variable needs to be pointing to a valid android SDK before you can do any command line wizardry for Android. On Windows, use: set ANDROID_HOME=C:/Path/To/Your/Android/Sdk; on Linux and macOS: export ANDROID_HOME=/Path/To/Your/Android/Sdk. Alternatively you can create a file called “local.properties” with the following content: sdk.dir /Path/To/Your/Android/Sdk.

iOS:

./gradlew ios:launchIPhoneSimulator

HTML:

./gradlew html:superDev

Then go to http://localhost:8080/index.html.

Gradle tasks are failing?

If whenever you invoke Gradle, the build or refresh fails to get more information, run the same command again and add the --debug parameter to the command, e.g.:

./gradlew lwjgl3:run --debug

This will provide you with a stacktrace and give you a better idea of why gradle is failing.

What to do next?

Now that you’re done with the set-up, you can get to do some real coding. Take a look at our post A Simple Game for a step-by-step guide.

© 2024 libGDX • This wiki is a community effort. If you find information out of date or want to add some more in-depth explanations, you are very welcome to do the necessary changes. Before contributing, please take a look at our Wiki Style Guide.

If you need additional help, check out our community on Discord!