react native state not updating

React native state not updating
Location in alert returns empty

function Home({ route, navigation }) {

const [location, setLocation] = useState('');

const _appStart = () => {
_location();
}

const _location = () => {
setLocation("Konum Ekle");
alert(location);
}

React.useEffect(() => {
const unsubscribe = navigation.addListener('focus', () => {
_appStart();
});

return unsubscribe;

}, [navigation]);

return (

{location}

)
}

const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor:'#ffff',
},
})

export default Home