使用react-native-responsive-screen，您可以根据屏幕大小使用值，如下所示:

import {widthPercentageToDP as wp, heightPercentageToDP as hp} from 'react-native-responsive-screen';

class Login extends Component {
  render() {
    return (
      <View style={styles.container}>
        <View style={styles.textWrapper}>
        </View>
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: { flex: 1 },
  textWrapper: {
    height: hp('70%'), // 70% of height device screen
    width: wp('80%')   // 80% of width device screen
  }
});

export default Login;