build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.
def getAppProp(String propName) {
    def propsFile = rootProject.file('app.properties')
    println rootProject
    if (propsFile.exists()) {
        def props = new Properties()
        props.load(new FileInputStream(propsFile))
        if (props[propName] != null) {
            return props[propName]
        } else {
            throw new GradleException('Unable to find property "' + propName + '" in properties file "' + propsFile + '".')
        }
    } else {
        throw new GradleException('Unable to find file "app.properties" in project root.')
    }
}

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:1.3.0'
        classpath 'com.neenbedankt.gradle.plugins:android-apt:1.4'

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

allprojects {
    repositories {
        jcenter()
    }
}