How to access nested dictionary in dart?

Question

I have this code:

 class Dev {
     static final config = const {
       'endpoints': const {
         'signIn': '/v1/auth/sign_in',
       },
       'apiBaseUrl': 'localhost:3000'
     };
    }

Im trying to access to the signIn property in the config variable, when i do config['endpoints'] it access the property correctly, but when i try

var signInEndpoint = config['endpoints']['signIn'];

It doesn't work, same when i try

var endpoints = config['endpoints'];
var signInEndpoint = endpoints['signIn'];

How can i correctly access signIn property in variable?, thanks in advance.

diegoveloper · Accepted Answer · 2018-09-01 05:45:46Z

1

That is because the endPoints value is an Object not dynamic, try this:

var signInEndpoint = (Dev.config['endpoints'] as dynamic)['signIn'];

answered Sep 1, 2018 at 5:45

diegoveloper

104k25 gold badges253 silver badges201 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Dinesh Balasubramanian · Accepted Answer · 2018-09-01 07:52:38Z

1

@Juan you tried two approaches know,

var signInEndpoint = config['endpoints']['signIn'];

which can fixed as per @diegoveloper's suggestion

var endpoints = config['endpoints'];
var signInEndpoint = endpoints['signIn'];

can be fixed like

Map endpoints = config['endpoints']; //Map<String, String> will be much better
var signInEndpoint = endpoints['signIn'];

Additional information:

I prefer not having dynamic type as it will create runtime errors only (no compile time error with dynamic/Object).

In your case Dev.config is of Map<String, Object>. Object can be casted to anything and it will create runtime errors.

So I changed the Dev class a bit. Please have a look

class Dev {
  static final Map<String, Map<String, String>> config = const {
    'endpoints': const {
      'signIn': '/v1/auth/sign_in',
      'apiBaseUrl': 'localhost:3000'
    },
  };
}
var signInEndpoint = Dev.config['endpoints']['signIn'] //will work

or like this

class Dev {

  static final Map<String, String> endpoints = const {
    'signIn': '/v1/auth/sign_in',
  };
  static final Map<String, String> config = const {
    'baseUrl': 'localhost:3000',
    'other': 'others'
  };
}
var signInEndpoint = Dev.endpoints['signIn']

answered Sep 1, 2018 at 7:52

Dinesh Balasubramanian

21.8k9 gold badges69 silver badges61 bronze badges

2 Comments

Juan Manuel Rodriguez A. Over a year ago

Thank you very much, this has given me more options to work with, i think i will use the second approach you have given me.

Dinesh Balasubramanian Over a year ago

Glad that it helped you

Collectives™ on Stack Overflow

How to access nested dictionary in dart?

2 Answers 2

Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related