Flutter: Selected value in dropdown list

Using @Jonah Williams's tip in the comments I came up with the following working example to a similar problem that I had:

import 'package:flutter/material.dart';

class StatusDialog extends StatefulWidget {

  @override
  State<StatefulWidget> createState() {
    return StatusDialogState();
  }
}

class StatusDialogState extends State<StatusDialog> {
  String _selectedText = "SSD";

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: Text("Status Update"),
      content: new DropdownButton<String>(
        hint: Text("Status"),
        value: _selectedText,
        items: <String>['SDD', 'Meeting', 'Home', 'Space']
            .map((String value) {
          return new DropdownMenuItem<String>(
            value: value,
            child: new Text(value),
          );
        }).toList(),
        onChanged: (String val) {
          setState(() {
            _selectedText = val;
          });
        },
      ),
      actions: <Widget>[
        FlatButton(
          child: Text("UPDATE"),
          onPressed: () {
            //.....
          },
        ),
      ],
    );
  }
}

void _buildStatusDialog(String documentID) {
  showDialog<void>(
    context: context,
    builder: (BuildContext context) {
      return StatusDialog();
    }
  );
}

Then you just need to add some logic to obtain _selectedText from StatusDialog - probably using a callback.