Converting JSON to Dart Classes

This tutorial shows you how to convert complex JSON response objects into a class structure in dart. We break down some of the most common examples of converting JSON to class structure as well as how to deal with nested class structures.
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[@kennyn.8233]

Just in time that I got stuck with nested object in dart class. Glad I found your tutorial. Thanks for sharing

[@Machiuka]

Awesome tutorial. It explains a lot about this complicated (for me anyway) topic. Thank you for sharing!

[@anmolbindra1]

Thorough tutorial Thanks Man

[@ItsLarry]

Best flutter and dart Chanel keep it up

[@aritrasanyal1485]

Thanks Bleyl Dev for this video, was kinda stuck with json_serializable unable to decode and all the instances were null for some reason

[@TGBPlayso]

thank you so much! keep at it!

[@mundocustom1485]

Great explanation, thanks for share buddy

[@andrevini8099]

I dont now why, when I use a jsonDecode, instead of receiving a Map I recieve a List, and I dont know what to do with it, anyone know why and what to do ?

[@StarBattle08]

why are you using the toString() method when printing?

[@AshutoshKumar-jl5vu]

hey, this one's the best explanation. Thanks

[@tameflame1229]

Why use a factory constructor? Sorry if silly question

[@lukas7338]

wondering this too... did you find out?

[@aakashchandrakar6359]

How to Fetch Subcollecation in New FirebaseFirestore in Flutter App Pls help

[@AhmadRifai-ey4uo]

plz show how to format number from API in datacell dart with thousand separator

[@memechallenge1161]

What if you have more than one coin.... how to store that data in a list of objects

[@BillBrutzman]

Thanks. Helpful but _ I have json from API from SQL _ several records _ I am trying to inject into a Flutter dataTable. A single data element helps but _

[@patricksingrin2788]

Thanks for the nice tutorial. Everything worked well for me until I tried another json. I’m trying to get the values for ‚projectName‘ & ‚clientName‘. I get an error back:
Error: Expected a value of type 'Map', but got one of type 'List'
The class looks like this:
---
import 'package:portfolio_web/model/fields_data.dart';
class ItemsData {
final FieldsData fieldsdata;
ItemsData({this.fieldsdata});
factory ItemsData.fromJson(Map json) {
return ItemsData(
fieldsdata: FieldsData.fromjson(json['items']),
);
}
}
---
The FieldsData class looks basically the same.
My guess is it’s because of the ‚items‘ structure. Sadly I couldn’t figure out how to solve it. I know it's probably hard to troubleshoot random code snippets but maybe you have an idea or can give me a hint. I would appreciate it.
My json basically looks like this:
{
"sys": {
"type": "Array"
},
"total": 11,
"skip": 0,
"limit": 100,
"items": [
{},
{
"sys": {},
"fields": {
"projectName": "Hello World!",
"clientName": „World Inc“,
"projectRoles": []
}
},
}

[@patricksingrin2788]

I actually found a solution. I used a if-loop to process each element of the array of objects and added them to the final list:
List list = new List.empty(growable: true);
for(int i=0; i

[@achmadirfanda]

hello world, did you know how to convert hash value (password) to string in dart?

[@alfianrudiyanto7772]

nice video

[@BleylDev]

Thanks!

[@szyszak9424]

always receving null value

[@BleylDev]

Sorry, this video is like 3 years outdated now if you didn’t see the time stamp…
I’d recommend just asking whatever issue you have to chatgpt if this doesn’t work for you

[@szyszak9424]

@@BleylDev i make it work. I was using rest API firebase and it generated special indentificators, after I looped trhough them and assign only values it works.

[@memechallenge1161]

You have few comments yet you don’t reply lol