build.gradle

buildscript {
    repositories {
        jcenter()
        google()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.1'

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

allprojects {
    repositories {
        jcenter()
        mavenLocal()
        mavenCentral()
        maven {
            url 'https://maven.google.com/'
            name 'Google'
        }
    }
}

apply plugin: 'com.android.library'

def computeCompileSdkVersion = { -> project.hasProperty("compileSdk") ? compileSdk : 24 }
def computeBuildToolsVersion = { ->
    project.hasProperty("buildToolsVersion") ? buildToolsVersion : "27.0.1"
}

android {
    compileSdkVersion computeCompileSdkVersion()
    buildToolsVersion computeBuildToolsVersion()

    defaultConfig {
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
    }
}

dependencies {
    def supportVer = "27.0.1"
    if (project.hasProperty("supportVersion")) {
        supportVer = supportVersion
    }
    compileOnly "com.android.support:support-v4:$supportVer"
    compileOnly "com.android.support:appcompat-v7:$supportVer"
}