Integrating Unity into Android applications

This page describes how to integrate the Unity Runtime Library into Android applications using the Unity as a Library feature.

You can use this feature to include Unity-powered features, such as 3D/2D Real-Time Rendering, AR Experience, 3D model interaction, or 2D mini-games, into your application. The Unity Runtime Library exposes controls to manage when and how to load, activate, and unload content within the application.

How it works

You don’t need to do anything different when you build your Gradle project from Unity.

Every Android Gradle project that Unity generates has the following structure:

• A library part in the unityLibrary module that you can integrate into any other Gradle project. This contains the Unity runtime and Player data.
• A thin launcher part in the launcher module that contains the application name and its icons. This is a simple Android application that launches Unity. You can replace this module with your own application.

To integrate Unity into another Android Gradle project, you must include the unityLibrary module of the generated Android Gradle project in your Android Unity Project through the settings.gradle file.

This repository contains example Projects and plug-ins that demonstrate how to integrate Unity into an Android app, along with further documentation.

To control a Player, relay an Intent to launch Unity activity and extend it if needed. For more information, see Android developer documentation on Intents and Intent Filters. You can also use the UnityPlayer Java API.

IUnityPlayerLifecycleEvents

IUnityPlayerLifecycleEvents provides a way to interact with two important lifecycle events of the Unity Player:

• Unload - The application calls IUnityPlayerLifecycleEvents.onUnityPlayerUnloaded when Application.Unload or UnityPlayer.unload() unloads the Unity Player. This puts the Unity Player in a paused state where it unloads all Scenes, but keeps everything else loaded in the memory.
• Quit - The application calls IUnityPlayerLifecycleEvents.onUnityPlayerQuitted when the Unity Player quits. The process that was running Unity ends after this call.

You can pass an instance of IUnityPlayerLifecycleEvents to the UnityPlayer constructor, or to override methods in subclasses of UnityPlayer and UnityPlayerActivity.

Limitaciones

Unity doesn’t control the runtime lifecycle, so Unity as a Library might not work for all possible use cases. Known limitations include:

• Unity as a Library only supports full-screen rendering, and doesn’t support rendering on part of the screen.
• You can’t load or integrate more than one instance of the Unity runtime.
• You might need to adapt third-party plug-ins (both native and managed) to work with the Unity runtime.

• Unity as a Library for Android added in 2019.3.NewIn20193