ufk ufk - 1 year ago 117
Dart Question

how to get values from a const object?

I created a const object at app.config.dart with the following code:

const configObj = const {
'webServer': const {
'appBaseHref' : "/"
'auth0': const {
'apiKey': "foo",
'domain': "bar",
'callbackUrl': "callback"

now in my main dart file I import the
and I try to get the values there and now idea how to do that.
produces the error
EXCEPTION: Class 'ImmutableMap' has no instance getter 'auth0'

so how do I do this ?


Answer Source

Dart doesn't support to access map entries with .

It should be:


Alternatively you can create classes for your configuration like

class WebServerConfig {
  final String appBaseHref;
  const WebServerConfig(this.appBaseHref);

class Auth0Config {
  final String apiKey;
  final String domain;
  final String callbackUrl;
  const Auth0(this.apiKey, this.domain, this.callbackUrl);

class MyConfig {
  final WebServerConfig webServer;
  final Auth0Config auth0;
  const MyConfig(this.webServer, this.auth0);      

const configObj = const MyConfig(
  const WebServerConfig("/"),
  const Auth0Config(

This way you also get proper auto-completion when you access the config properties and can use the simple . notation to access properties.

Recommended from our users: Dynamic Network Monitoring from WhatsUp Gold from IPSwitch. Free Download