How to change Future Dynamic into String?

Question

I am following old tutorial, and I get an error on ImageUrl in last line of code:

"Future dynamic can't be assigned to argument type String".

How can I fix that?

class _MyAppState extends State<MyApp> {

  static FirebaseStorage storage = FirebaseStorage(
    storageBucket: 'gs://natapp-7d2db/storage/natapp-7d2db.appspot.com/files'
  );

  static StorageReference imageRef = storage.ref().child('cake.png');

  final imageUrl = imageRef.getDownloadURL();

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(brightness: Brightness.dark),
      home: Container(
        child: Image.network(imageUrl),
      ),
    );
  }
}

EDIT: I used

child: Image.network(imageUrl.toString)

Does this answer your question? [What is a Future and how do I use it?](https://stackoverflow.com/questions/63017280/what-is-a-future-and-how-do-i-use-it) — nvoigt, Jul 29 '20 at 14:12

Jitesh Mohite · Answer 1 · 2020-07-29T13:21:37.950

1

Replace Container with Use FutureBuilder, as FutureBuilder is a widget which used for an async callback which runs on Future

FutureBuilder<String>(
      future: imageRef.getDownloadURL(),
      builder: (context, snapshot) {
        if (snapshot.hasData) {
           return Container(
                child: Image.network(snapshot.data));
        }

        if (snapshot.hasError) return WidgetThatShowsError();

        // by default show progress because operation is async and we need to wait for result
        return CircularProgressIndicator();
      },
    );

edited Jul 29 '20 at 13:21

answered Jul 29 '20 at 13:17

Jitesh Mohite

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correct me if i am wrong but the future should contain imageRef.getDownloadURL(). – Zeeshan Hussain Jul 29 '20 at 13:20
@ZeeshanHussain: Was supposed to update the answer, Anyway thanks for your observation. – Jitesh Mohite Jul 29 '20 at 13:22

How to change Future Dynamic into String?

1 Answers1