Map json to dart objects - json

Question

I'm looking for some direction on mapping json to an object. I'm trying to use live data from a web api. When I run the code I get the following error: Class '_LinkedHashMap' has no instance getter 'iterator'.
Here's what I'm trying to do:
import 'package:angular/angular.dart';
import 'dart:convert';
#NgController(
selector: '[movies]',
publishAs: 'ctrl'
)
class MoviesController {
// vars
bool moviesLoaded = false;
String nameToSearch = 'life';
Http _http;
List<MovieBrief> movies = [];
// constructor
MoviesController( Http this._http ) {
_loadData();
}
// functions
void _loadData() {
moviesLoaded = false;
// _http.get('http://www.omdbapi.com/?s=' + nameToSearch)
_http.get('movies_briefs.json')
.then((HttpResponse response) {
for (Map mb in response.data) {
movies.add(new MovieBrief.fromJsonMap(mb));
}
moviesLoaded = true;
},
onError: (Object obj) {
print(obj);
}
);
}
}
class MovieBrief {
String title;
String year;
String imdbId;
String type;
MovieBrief(this.title, this.year, this.imdbId, this.type);
String toJsonString() {
Map data = {"Search": [
{
"Title" : title,
"Year" : year,
"imdbID" : imdbId,
"Type" : type
}]};
return JSON.encode(data);
}
factory MovieBrief.fromJsonMap( Map json ) {
return new MovieBrief( json['Title'], json['Year'], json['imdbID'], json['Type']);
}
}
Here's a sample of the json results returned by the web api:
{
"Search": [
{
"Title": "Life of Pi",
"Year": "2012",
"imdbID": "tt0454876",
"Type": "movie"
},
{
"Title": "Life Is Beautiful",
"Year": "1997",
"imdbID": "tt0118799",
"Type": "movie"
},
{
"Title": "Life of Brian",
"Year": "1979",
"imdbID": "tt0079470",
"Type": "movie"
},
{
"Title": "It's a Wonderful Life",
"Year": "1946",
"imdbID": "tt0038650",
"Type": "movie"
},
{
"Title": "A Bug's Life",
"Year": "1998",
"imdbID": "tt0120623",
"Type": "movie"
},
{
"Title": "A Bug's Life",
"Year": "1998",
"imdbID": "tt0174716",
"Type": "movie"
},
{
"Title": "The Tree of Life",
"Year": "2011",
"imdbID": "tt0478304",
"Type": "movie"
},
{
"Title": "The Life Aquatic with Steve Zissou",
"Year": "2004",
"imdbID": "tt0362270",
"Type": "movie"
},
{
"Title": "Lara Croft Tomb Raider: The Cradle of Life",
"Year": "2003",
"imdbID": "tt0325703",
"Type": "movie"
},
{
"Title": "Dan in Real Life",
"Year": "2007",
"imdbID": "tt0480242",
"Type": "movie"
}
]
}

Answer 1

Have you looked at the json_object package? This parses a json string and creates properties on the resulting object, in your case you would have say film.title, film.year etc. You can store each json_object in a list.

Answer 2

I'm guessing response.data is a map, so you can't iterate on it with a for loop. You need to either use response.data.keys, response.data.values, or use the forEach method on the map, which provides both.
response.data.forEach((key, value) => movies.add(Etc)
As per the other response, something like json_object is also worth looking into, but that's a way of avoiding hard coding the field mappings.