reactnativecode.jsx

import { NativeModules} from 'react-native';
const { VideoPlayerManager } = NativeModules;

fullScreen = () => {
  if (Platform.OS === 'android') {
    VideoPlayerManager.showVideoPlayer(url);
  } else if (this.player) {
    this.player.presentFullscreenPlayer();
  }
}

render () {
    return (<>
      ...
          <Video
            source={{uri: url }}
            style={{width: 250, height: 250 }}
            onFullscreenPlayerDidDismiss={this.stopVideo}
            ref={(ref) => {
              this.player = ref;
            }}
          />
          <Button onPress={this.fullScreen} style={{backgroundColor: 'blue'}} color={'blue'} title={'fullScreen'}></Button>
      ...
    </>)
  }