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

import com.github.ajalt.reprint.core.Reprint;      // <- add this line
import co.eleken.react_native_touch_id_android.FingerprintPackage;    // <- add this line

public class MainApplication extends Application implements ReactApplication {

...

  private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {

    @Override
    protected List<ReactPackage> getPackages() {
      return Arrays.<ReactPackage>asList(
          new MainReactPackage(),
          new FingerprintPackage()     // <- add this line
      );
    }
    
  };

  @Override
  public void onCreate() {
    super.onCreate();
    Reprint.initialize(this); // <- add this line
  }

...

Finger.isSensorAvailable()
    .then((isAvailable) => {   })
    .catch(error => {   });

Finger.requestTouch()
    .then(success => {  })
    .catch(error => {  });

import Finger from 'react-native-touch-id-android'

export default class TouchTest extends Component {

  componentDidMount() {
    Finger.isSensorAvailable()
      .then((isAvailable) => {
        ToastAndroid.show('Sensor is available and is waiting for touch', ToastAndroid.SHORT);
        this.touchAuth()
      })
      .catch(error => {
        ToastAndroid.show(error, ToastAndroid.SHORT);
      });
  }

  touchAuth(){
    Finger.requestTouch()
      .then(success => {
        ToastAndroid.show('Access granted', ToastAndroid.SHORT);
      })
      .catch(error => {
        ToastAndroid.show(error, ToastAndroid.SHORT);
      });
  }

  render() {
    return (    

        ...

    );
  }

  componentWillUnmount(){
    Finger.dismiss()
  }
}