android-samples/tutorials/java/StyledMap/app/build.gradle

apply plugin: 'com.android.application'

// Set the properties within `local.properties` into a `Properties` class so
// that values within `local.properties` (e.g. Maps API key) are accessible in
// this file.
Properties properties = new Properties()
if (rootProject.file("local.properties").exists()) {
    properties.load(rootProject.file("local.properties").newDataInputStream())
}
def mapsApiKey = properties.getProperty("MAPS_API_KEY", "")

android {
    compileSdkVersion 29
    buildToolsVersion '28.0.3'
    defaultConfig {
        applicationId "com.example.styledmap"
        minSdkVersion 16
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

        // Read the API key from local.properties into R.string.maps_api_key
        resValue "string", "maps_api_key", mapsApiKey

        // To add your Maps API key to this project:
        // 1. Open the root project's local.properties file
        // 2. Add this line, where YOUR_API_KEY is your API key:
        //        MAPS_API_KEY=YOUR_API_KEY
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'com.google.android.gms:play-services-maps:17.0.0'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
}