This is my code
SharedPreferences sharedPreferences;
token() async {
sharedPreferences = await SharedPreferences.getInstance();
return "Lorem ipsum dolor";
}
When I print, I got this message on debug console
Instance of 'Future<dynamic>'
How I can get string of "lorem ipsum..." ? thank you so much
token() is async which means it returns Future. You can get the value like this:
SharedPreferences sharedPreferences;
Future<String> token() async {
sharedPreferences = await SharedPreferences.getInstance();
return "Lorem ipsum dolor";
}
token().then((value) {
print(value);
});
But there is a better way to use SharedPreferences. Check docs here.
In order to retrieve any value from async function we can look at the following example of returning String value from Async function. This function returns token from firebase as String.
Future<String> getUserToken() async {
if (Platform.isIOS) checkforIosPermission();
await _firebaseMessaging.getToken().then((token) {
return token;
});
}
Fucntion to check for Ios permission
void checkforIosPermission() async{
await _firebaseMessaging.requestNotificationPermissions(
IosNotificationSettings(sound: true, badge: true, alert: true));
await _firebaseMessaging.onIosSettingsRegistered
.listen((IosNotificationSettings settings) {
print("Settings registered: $settings");
});
}
Receiving the return value in function getToken
Future<void> getToken() async {
tokenId = await getUserToken();
}
print("token " + tokenId);
Whenever the function is async you need to use await for its response otherwise Instance of 'Future' will be output
