expo-secure-store — token ধরে রাখা ও login gate

npx expo install expo-secure-store

import * as SecureStore from "expo-secure-store";

const KEY = "auth.token";

export async function saveToken(token) {
  await SecureStore.setItemAsync(KEY, token);
}

export async function getToken() {
  return SecureStore.getItemAsync(KEY);
}

export async function logout() {
  await SecureStore.deleteItemAsync(KEY);
}

const [token, setToken] = useState(null);
const [ready, setReady] = useState(false);

useEffect(() => {
  getToken().then((value) => {
    setToken(value);
    setReady(true);
  });
}, []);

if (!ready) return <ActivityIndicator />;
return token ? <Home /> : <Login onSuccess={saveToken} />;