build.gradle

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

buildscript {
    repositories {
        jcenter()
        google()
        maven { url 'https://maven.fabric.io/public' }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.1'
        classpath 'io.fabric.tools:gradle:1.+'

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

allprojects {
    repositories {
        jcenter()
        google()
        maven { url "https://jitpack.io" }
    }
}

ext {
    // Sdk and tools
    minSdkVersion = 16
    targetSdkVersion = 26
    compileSdkVersion = 26
    buildToolsVersion = '26.0.2'

    // App dependencies
    supportLibraryVersion = '27.0.2'
    retrofitVersion = '2.3.0'
    okHttp3Version = '3.9.0'
}