text: import React from 'react';
  import { View, Text, StyleSheet } from 'react-native';
  
  export default props => (
  	<View style={styles.topo}>
  		<Text style={styles.txtTitulo}>Calculadora 1.0</Text>
  	</View>	
  );
  
  const styles = StyleSheet.create({
  	topo: {
  		backgroundColor: '#2196F3',
  		padding: 10,
  		alignItems: 'center',
  	},
  	txtTitulo: {
  		fontSize: 25,
  		color: '#fff'
  	}
  });