flutter_codex_storage_03.dart

// This is the variable that stores the image URL.

String imageUrl = '';

// This is the variable that stores the image extension.

String ext = '';

// This is the function to fetch the image from the storage.

Future fetchImage() async {
  var ref = _storage.ref().child('user.avatar${this.ext}');

  if (ref != null) {
    String url = await ref.getDownloadURL();

    setState(() {
      imageUrl = url;
    });
  }
}

// And this is the button that request the avatar of the user.

RaisedButton(
  child: Text('Show Avatar'),
  color: Colors.orangeAccent,
  onPressed: fetchImage,
)

// After fetching the avatar, we will show it with this widget.

isLogged && this.imageUrl != ''
  ? Container(
      width: 200,
      height: 200,
      child: Image.network(
        this.imageUrl,
        fit: BoxFit.fitWidth,
      ),
    )
  : Container(),