build.gradle

def safeExtGet(prop, fallback) {
    rootProject.ext.has(prop) ? rootProject.ext.get(prop) : fallback
}

apply plugin: 'com.android.library'

def DEFAULT_COMPILE_SDK_VERSION             = 26
def DEFAULT_BUILD_TOOLS_VERSION             = "26.0.2"
def DEFAULT_TARGET_SDK_VERSION              = 26
def DEFAULT_ANDROIDX_APPCOMPAT_VERSION      = "1.6.1"

android {
    compileSdkVersion rootProject.hasProperty('compileSdkVersion') ? rootProject.compileSdkVersion : DEFAULT_COMPILE_SDK_VERSION
    buildToolsVersion rootProject.hasProperty('buildToolsVersion') ? rootProject.buildToolsVersion : DEFAULT_BUILD_TOOLS_VERSION

    defaultConfig {
        minSdkVersion safeExtGet('minSdkVersion', 16)
        targetSdkVersion rootProject.hasProperty('targetSdkVersion') ? rootProject.targetSdkVersion : DEFAULT_TARGET_SDK_VERSION
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    def androidXAppCompatVersion = rootProject.hasProperty('androidXAppCompatVersion') ? rootProject.androidXAppCompatVersion : DEFAULT_ANDROIDX_APPCOMPAT_VERSION

    implementation fileTree(dir: 'libs', include: ['*.jar'])
    testImplementation 'junit:junit:4.12'
    implementation "androidx.appcompat:appcompat:$androidXAppCompatVersion"
    implementation "com.facebook.react:react-native:+" // From node_modules
}