Here is the new code:
import { NavigationContainer, useNavigationState, useNavigation } from '@react-navigation/native';import { createStackNavigator } from '@react-navigation/stack';import { Toolbar } from 'react-native-material-ui';import * as React from 'react';import { Platform, StatusBar, StyleSheet, View, Text } from 'react-native';import BottomTabNavigator from '../../navigation/BottomTabNavigator';import LinkingConfiguration from '../../navigation/LinkingConfiguration';import CatHome from '../../screens/subScreens/CatHome';const Stack = createStackNavigator();export default function Navigator() { return (<View style={styles.container}> {Platform.OS === 'ios'&& <StatusBar barStyle="dark-content" />}<NavigationContainer linking={LinkingConfiguration}><Stack.Navigator screenOptions={{ headerLeft: null, headerTitle: props => <SearchBar {...props} />, headerStyle: { backgroundColor: '#9acd32', } }}><Stack.Screen name="Root" component={BottomTabNavigator} /><Stack.Screen name="CatHome" component={CatHome} /></Stack.Navigator></NavigationContainer></View> );}function SearchBar (){ const navigation = useNavigation(); //const { navigate } = this.props.navigation; return(<Toolbar leftElement= {backOption()} onLeftElementPress= {()=>navigation.goBack()} //isSearchActive= {true} style={{ container: styles.searchBar, }} centerElement="DIRECTAPP" searchable={{ autoFocus: true, placeholder: 'Buscar', }} rightElement={{ menu: { icon: "more-vert", iconProps : { size: 30, color: 'gray', }, labels: ["Locación", "Contáctanos"] } }} onRightElementPress={ (label) => { console.log(label) }} /> );}function backOption (){ //const Route=useRoute(); const state = useNavigationState(state => state); const routeName = (state.routeNames[state.index]); //console.log(routeName); if (routeName=='Root') { return '' } else { return 'arrow-back' };}const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: '#fff', }, searchBar: { backgroundColor: '#9acd32', width: '100%', shadowOffset: { width: 1, height: 13}, shadowOpacity: 0.1, } });