The following resources go further in depth on using Corona Native for Android.
Download and install Android Studio, the official IDE for Android development.
New projects can easily be created by using template files as a starting point. Project template can be found:
To start a new project, copy the
App folder to desired location and rename it. Start Android Studio, click "Open an existing Android Studio Project", and select
android directory from copied
Note, that opening
Inside your copy of the
App folder, the following files/directories are of primary concern:
Corona— This folder represents a classic Corona project, containing files like
main.lua, app icons, etc. By default,
build.gradle (Module: App)
android— Contains all of the
build.gradle— This is the main build script and it's also where you set up some application settings like version and what SDK versions to use.
libs/— This is where
.jarplugins that your app relies upon should go.
AndroidManifest.xml— This is where you configure application settings such as name, permissions, etc.
java/— This is where the Java source files for your app should go. Because the package is
com.mycompany.app, this is where the files are located by default. You should modify this according to the package name you specify.
jniLibs/— This is where
.soplugins that your app relies upon should go.
plugin— For plugins, there are additional files and directories of interest:
build.gradle— This is the build script that creates the plugin. The output is a
.jarfile. The only files included in the
.jarare those located in
plugin/src/main/, whether they are code or resources.
libs— This is where
.jarplugins that your plugin relies upon should go.
AndroidManifest.xml— This is where you set up the plugin's package name.
LuaLoader.java— This is the code for the Lua library
plugin.libraryon the Android side.
jniLibs/— This is where
.soplugins that your plugin relies upon should go.
The following steps briefly outline the flow of the
android/app/src/main/java/com/mycompany/app/CoronaApplication.java — At launch time,
CoronaApplication.java is instantiated. It adds a private class to be notified of various
main.lua is invoked, the
onCreate() method is invoked. At this point, OpenGL is set up and all Corona frameworks are available.
Corona/main.lua — In the Lua code,
plugin.library is loaded via
require(). The Corona engine will then look for a corresponding Java class called
plugin.library.LuaLoader and invoke it. The name of this class is dynamic and is constructed using the original library name passed to
require() as the package name for a
LuaLoader class. The
LuaLoader class is expected to implement the JNLua interface
android/plugin/src/main/java/plugin/library/LuaLoader.java — When the
LuaLoader is resolved, the class is instantiated with the default constructor. The
invoke() method is then called by Lua via JNLua and does all the heavy lifting, for example creating the Lua library table, registering the Lua methods like
show(), and then leaving the table at the top of the Lua stack.
Note that the
LuaLoader class is instantiated once for the lifetime of the process, much like a
.so file is typically loaded once for the lifetime of the process. Also note that the
invoke() method is called once for each Lua state that does a
require() — this corresponds to being called once each time the
CoronaActivity is instantiated.
To bridge Lua and Java code, you'll use functionality made available by JNLua. This allows you to add libraries and functions in Lua that call directly into Java.
The native APIs for Android are available as a JavaDoc.
For information on working with Android Runtime Permissions in Android 6.0 or newer, please read our Android Runtime Permission Support guide.
To build a Corona Native project from Android Studio, simply use the Run button on the top bar of icons. This will build your project, sign it, and prompt you to select a deployment target. The built
.apk is signed with either a keystore you've specified in the
android/app/build.gradle script, or the default
debug.keystore if none is provided.
Android Studio has several other