Android plug-in for Kobalt.

Features

The Kobalt Android plug-in offers the following features:

• Automatic SDK downloading
• Resource merging
• Manifest merging
• Predexing
• Generation of apk files
• Install and run activities on the device

It also supports features already offered by Kobalt itself:

• BuildConfig
• Incremental tasks

The plug-in uses Google's Android build library, which guarantees that all these operations are being performed the same way as the official Gradle Android plug-in. This also makes it easier to add new functionalities as they get added to the official Android builder library.

For a full example of a complex Android application being built with Kobalt, take a look at the Kobalt u2020 fork.

SDK Management

Kobalt will automatically everything that is necessary to build Android applications, including:

• The Android SDK
• Support libraries
• Build tools
• etc...

The plug-in will start by looking if $ANDROID_HOME is defined and if it is, use it. It it's not defined, the SDK will be downloaded in ~/.android-sdk. You can find more details about this feature in this article.

Build file

You introduce Android inside your project by including the Kobalt Android plug-in:

val bs = buildScript {
    // ...
    plugins("com.beust:kobalt-android:$kobaltAndroid")
}

Import the symbols:

import com.beust.kobalt.plugin.android.*

You can now use the android directive inside your project:

val p = project {
    // ...

    android {
        defaultConfig {
            minSdkVersion = 15
            versionCode = 100
            versionName = "1.0.0"
            compileSdkVersion = "23"
            buildToolsVersion = "23.0.1"
            applicationId = "com.beust.myapp"
        }
    }

These fields should look familiar to Android developers. The defaultConfig directive defines values that will apply to all variants of your build, but each variant can override any of these values.

Tasks

The Kobalt Android plug-in introduces a few new tasks (you can get the full list with ./kobaltw --tasks with the plug-in enabled). The ones you will likely use the most often are:

• install. Build and install the apk on the device.
• run. Run the main activity of your application on the device.

The plug-in also creates tasks for each of the variants found in your build file, e.g. installProductionDebug, runInternalRelease, etc...

Libraries

By default, an Android project will output an apk but you can request an aar file to be produced with the aar{} directive:

val p = project {
    // ...

    android {
        aar {
        }
    }
}

This directive lets you specify additional configuration parameters such as the name of the aar file to produce. Refer to the documentation of the AarConfig class for more details.