vds_quiz/vds-app/App/components/Banner.js

import React from "react"
import { View, StyleSheet, StatusBar, Text, Dimensions } from "react-native"
import { colors, texts, credentials } from "./Variables"

import { BannerAd, BannerAdSize, TestIds } from 'react-native-google-mobile-ads'
const adUnitId = __DEV__ ? TestIds.INTERSTITIAL : 'ca-app-pub-4145771316565790/1848957462'

const screen = Dimensions.get("window")

const styles = StyleSheet.create({
  container: {
    //backgroundColor: colors.yellow,
    flex: 1,
    alignItems: "center",
    justifyContent: "center",
    marginTop: 20,
    height: 100,
    width: "100%"
  }
})

export const Banner = () => {

  let banner

  if(__DEV__) {
    banner = <Text>DEV BANNER</Text>
  } else {
    banner = <BannerAd size={BannerAdSize.LARGE_BANNER} unitId={adUnitId} />
  }
  return (
    <View style={styles.container}>
      {banner}
    </View>
  )
}