json_object_lite 4.0.2 copy "json_object_lite: ^4.0.2" to clipboard
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Allow use of JSON Maps in dot notation format without using mirrors.

example/example.dart

//
// This example is taken from the following article :-
// http://www.dartlang.org/articles/json-web-service/
//

import 'package:json_object_lite/json_object_lite.dart';

// ignore_for_file: omit_local_variable_types
// ignore_for_file: unnecessary_final
// ignore_for_file: cascade_invocations
// ignore_for_file: avoid_print

/// The Dart 2.0 update has changed how JsonObjectLite is used, previously
/// you could do this :-
///
/// JsonObjectLite o = new JsonObjectLite.fromJSonString('........');
/// print(o.bob);
/// print(o.fred);
/// ....
///
/// If you do this now the o.bob line will be flagged by the analyser as
/// 'the getter bob is not defined.....' which is correct, its not.
/// This was suppressed in Dart 1.0 by annotating the class with 'proxy'.
/// This annotation has been deprecated in Dart 2.0 hence the error.
///
/// The fix for Dart 2.0 is to do this :-
/// dynamic o = new JsonObjectLite.fromJSonString('........');
///
/// Declaring the created object as dynamic gives the analyzer
/// no clues about the objects structure and hence it produces no errors.
///
/// This is unfortunate in the fact the user code has to change to
/// accommodate this but in the long run its cleaner as we now know that
/// we don't know the object structure if you see what I mean.
///
/// An example taken from the dartlang article for JSON object, found here
/// https://webdev.dartlang.org/articles/get-data/json-web-service.

class LanguageWebsite extends JsonObjectLite<dynamic> {
  LanguageWebsite(); // default constructor (empty) implementation

  factory LanguageWebsite.fromJsonString(String json) {
    // from JSON constructor implementation
    final LanguageWebsite languageWebsite =
        LanguageWebsite(); // create an empty instance of this class
    // Create an instance of JsonObjectLite, populated with the json string and
    // injecting the _LanguageWebsite instance.
    final JsonObjectLite<dynamic> jsonObject =
        JsonObjectLite<dynamic>.fromJsonString(json, languageWebsite);
    return jsonObject
        as LanguageWebsite; // return the populated JsonObject instance
  }

  factory LanguageWebsite.fromJsonObject(JsonObjectLite<dynamic> jsonObject) =>
      JsonObjectLite.toTypedJsonObjectLite(jsonObject, LanguageWebsite())
          as LanguageWebsite;
}

class Language extends JsonObjectLite<dynamic> {
  Language(); // empty, default constructor

  factory Language.fromJsonString(String json) =>
      JsonObjectLite<dynamic>.fromJsonString(json, Language()) as Language;
  // as _LangaugeWebsite, return an instance
  // of JsonObjectLite, containing the json string and
  // injecting a _Language instance
}

int main() {
  const String responseText = '''
{
  "language": "dart", 
  "targets": ["dartium","javascript"], 
  "website": {
    "homepage": "www.dartlang.org",
    "api": "api.dartlang.org"
  }
}''';
  final dynamic data = Language.fromJsonString(responseText);

  // Tools can now validate the property access
  print(data.language); // should be dart
  print(data.targets[0]); // should be dartium

  // Nested types are also strongly typed
  final dynamic website = LanguageWebsite.fromJsonObject(
    data.website,
  ); // contains a JsonObjectLite
  print(website.homepage);
  website.isImmutable = false; // Now we can extend it
  website.homepage = 'http://www.dartlang.org';
  print(website.homepage);

  return 0;
}
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Allow use of JSON Maps in dot notation format without using mirrors.

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www.darticulate.com

License

MIT (license)

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