How to add Android Kotlin files to a Cordova Plugin project

Question

Is it possible to add Android Kotlin files to a Cordova Plugin project or is only Java supported?

<?xml version="1.0" encoding="UTF-8"?>
<plugin xmlns="http://apache.org/cordova/ns/plugins/1.0"
        version="0.0.1">

  <!-- android -->
  <platform name="android">

    <source-file src="src/android/nl/companyname/kotlin/ScanMode.kt" target-dir="src/nl/companyname/kotlin"/>

  </platform>

</plugin>

The Java files show up, but the Kotlin files don't. I also don't see any plugin that has it.

Answer 1

add the following in config.xml

<preference name="GradlePluginKotlinEnabled" value="true" />
<preference name="GradlePluginKotlinCodeStyle" value="official" />
<preference name="GradlePluginKotlinVersion" value="1.3.50" />

also note where to put the kotlin files, i.e. src/main/kotlin///

using:

<source-file src="src/android/file.kt" target-dir="app/src/main/kotlin/xx/yy/zz" />

and add the below to your plugin's gradle.build if the kotlin files aren't picked up by your project

android {
    sourceSets {
        main.java {
            srcDirs += 'src/main/kotlin'
        }
    }
}

This answer is referenced from: https://stackoverflow.com/a/63872580/10999673

I modifed an example repository to test this:

https://github.com/kilisio/cordova-plugin-hello-kotlin.git