react-native-video/examples/basic/android/build.gradle

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

buildscript {
    ext {
    buildToolsVersion = "28.0.3"
    minSdkVersion = 16
    compileSdkVersion = 28
    targetSdkVersion = 28
    supportLibVersion = "28.0.0"

}
    repositories {
        jcenter()
        google()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.4.1'

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

allprojects {
    repositories {
        mavenLocal()
        maven {
           url 'https://maven.google.com'
        }
        maven {
           url "https://jitpack.io"
        }
        jcenter()
        maven {
            // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
            url "$rootDir/../node_modules/react-native/android"
        }
    }
}