How to work with progress indicator in flutter?

Question

I\'m newbie in flutter and wanted to know what is better way to add CircularProgressIndicator in my layout. For example, my login view. This view have username,

Answer 1

You can do it for center transparent progress indicator

Future _submitDialog(BuildContext context) async {
  return await showDialog(
      context: context,
      barrierDismissible: false,
      builder: (BuildContext context) {
        return SimpleDialog(
          elevation: 0.0,
          backgroundColor: Colors.transparent,
          children: [
            Center(
              child: CircularProgressIndicator(),
            )
          ],
        );
      });
}