text: import React, { Component } from 'react'
  import { Text, View, StyleSheet, BackHandler, Dimensions, SafeAreaView, ImageBackground, Image, TextInput, TouchableOpacity, Modal, ActivityIndicator, Alert } from 'react-native'
  import { Container, Header, Content, Form, Item, Input, Label } from 'native-base';
  
  let SCREENWIDTH= Dimensions.get('screen').width;
  let SCREENHEIGHT= Dimensions.get('screen').height;
  export default class Logout extends Component {
      componentDidMount() {
          BackHandler.addEventListener('hardwareBackPress', this.handleBackPress);
      }
  
      componentWillUnmount() {
          BackHandler.removeEventListener('hardwareBackPress', this.handleBackPress);
      }
  
      handleBackPress = () => {
          this.props.navigation.navigate('HomeTABS');
          // this.goBack(); // works best when the goBack is async
          return true;
      }
      render() {
          return (
              <SafeAreaView style={styles.container}>
              <View style={styles.container}>
                  <Text style={styles.context}> Logout </Text>
              </View>
              </SafeAreaView>
          )
      }
  }
  const styles = StyleSheet.create({
      container:{
          flex:1,
          backgroundColor:'#fff',
          justifyContent:'center',
      },
      context:{
          alignSelf:'center',
          textAlign:'center'
      }
  })