build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    ext.kotlin_version = '1.1.3-2'
    ext.android_plugin_version = "2.3.3"

    repositories {
        jcenter()
    }

    dependencies {

        classpath "com.android.tools.build:gradle:$android_plugin_version"
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

task wrapper(type: Wrapper) {
    gradleVersion = "4.0"
}

// Disable incremental builds on the build server
project.ext.preDexLibs = !project.hasProperty('disablePreDex')

subprojects {
    project.plugins.whenPluginAdded { plugin ->
        if ("com.android.build.gradle.AppPlugin".equals(plugin.class.name)) {
            project.android.dexOptions.preDexLibraries = rootProject.ext.preDexLibs
        } else if ("com.android.build.gradle.LibraryPlugin".equals(plugin.class.name)) {
            project.android.dexOptions.preDexLibraries = rootProject.ext.preDexLibs
        }
    }
}