text: import { createStackNavigator } from '@react-navigation/stack';
  import { StartActivity } from './components/activities/StartActivity';
  import { ProductActivity } from './components/activities/ProductActivity';
  import { RegisterActivity} from './components/activities/RegisterActivity';
  import { VerifyActivity} from './components/activities/VerifyActivity';
  import { UserActivity} from './components/activities/UserActivity';
  import { NavigationContainer } from '@react-navigation/native';
  import Icon from 'react-native-vector-icons/Ionicons';
  import React from 'react';
  import { AppLoading } from 'expo';
  import { useFonts } from 'expo-font';
  import {TouchableOpacity} from 'react-native';
  
  
  const Stack = createStackNavigator();
  export default Init = () => {
    let [_FontsLoaded] = useFonts({
      'Appfont': require('@assets/fonts/youre_gone.ttf'),
      'Primary': require('@assets/fonts/MiriamLibre-Regular.ttf'),
      'PrimaryBold': require('@assets/fonts/MiriamLibre-Bold.ttf'),
    });
    if (_FontsLoaded) {
      return (
        <NavigationContainer>
          <Stack.Navigator>
            <Stack.Screen name="StartActivity" component={StartActivity} options={{ 
              headerTransparent: true,
                //headerLeft: ()=> <Icon name="md-home" size={25}/> ,
              title:'' }} />
            <Stack.Screen name="ProductActivity" component={ProductActivity} options={({ navigation, route })=> ({ 
                  title:'', headerRight: ()=> 
                  <TouchableOpacity onPress={()=>{navigation.navigate('UserActivity')}}> 
                    <Icon name="ios-contact" size={25}  /> 
                  </TouchableOpacity>,
                  headerRightContainerStyle:{marginRight:15}})} />
            <Stack.Screen name="RegisterActivity" component={RegisterActivity} options={{ headerTransparent: true,title:''}} />
            <Stack.Screen name="VerifyActivity" component={VerifyActivity} options={{ headerTransparent: true,title:''}} />
            <Stack.Screen name="UserActivity" component={UserActivity} options={{ headerTransparent: false,title:'Settings'}} />
          </Stack.Navigator>
        </NavigationContainer> 
      )
    } else
      return <AppLoading />
  }
  
  