How do I search through data in flutter app - json

Question

I am new to flutter and I was following a tutorial that shows how to search through data. I cannot recreate that using my own example. I would like to know how to search through data in a ListView from this json data.
{
"success": "true",
"data": [
{
"id": 1,
"name": "football"
},
{
"id": 2,
"name": "rugby"
},
{
"id": 3,
"name": "basketball"
},
{
"id": 4,
"name": "hockey"
},
{
"id": 5,
"name": "tennis"
},
{
"id": 6,
"name": "golf"
}
]
}
Displayed using this code
if (snapshot.hasData) {
return ListView.builder(
itemCount: sports.games.length,
itemBuilder: (context, index) {
if (sports.games.length > 0) {
final x = sports.games[index];
final y = sports.games[index].id.toString();
return ListTile(
title: Text(y),
subtitle: Text(x.name),
);
}
},
);
}
},

Answer 1

First your JSON file will return as a Map, according to this answer at
Unhandled Exception: InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List<dynamic>
for your problem, here is the solution. First you need create a model like this, can be place at separate file or can be place at same file too
class Sports {
int id;
String name;
Sports({
this.id,
this.name,
});
factory Sports.fromJson(Map<String, dynamic> json) {
return Sports(id: json['id'], name: json['name']);
}
}
than here it's the main.dart
import 'package:aberdeen/model.dart';
import 'package:flutter/material.dart';
import 'dart:convert';
void main() {
runApp(MyApp());
}
class MyApp extends StatefulWidget {
MyApp({Key key}) : super(key: key);
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyApp> {
TextEditingController controller = new TextEditingController();
List<Sports> array = [];
List<Sports> _filtered = [];
List<Sports> _null_filtered = [];
String jsonTest =
'{"success": "true","data": [{"id": 1,"name": "football"},{"id": 2,"name": "rugby"},{"id": 3,"name": "basketball"},{"id": 4,"name": "hockey"},{"id": 5,"name": "tennis"},{"id": 6,"name": "golf"}]}';
void initState() {
super.initState();
test();
}
void _alterfilter(String query) {
List<Sports> dummySearchList = [];
dummySearchList.addAll(_filtered);
if (query.isNotEmpty) {
List<Sports> dummyListData = [];
dummySearchList.forEach((item) {
if (item.name.contains(query)) { //if you want to search it order by id you can change item.name.contains to item.id.contains
dummyListData.add(item);
}
});
setState(() {
_filtered.clear();
_filtered.addAll(dummyListData); //dummyListData will place all the data that match at your search bar
});
return;
} else {
setState(() {
_filtered.clear();
_filtered.addAll(_null_filtered); //_null_filtered will place all the data if search bar was empty after enter a words
});
}
}
Future<Sports> test() async {
Map<String, dynamic> tagObjsJson = json.decode(jsonTest);
List<dynamic> data = tagObjsJson["data"];
setState(() {
for (Map Data in data) {
array.add(Sports.fromJson(Data));
}
_filtered.addAll(array);
_null_filtered.addAll(array);
for (int a = 0; a < _filtered.length; a++) {
print(_filtered[a].name);
}
});
}
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: [
Container(
alignment: Alignment.center,
child: Container(
margin: const EdgeInsets.only(top: 50),
width: 300,
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(20),
border: Border.all(
width: 1,
color: Color.fromRGBO(11, 189, 180, 1),
style: BorderStyle.solid)),
child: TextField(
decoration: InputDecoration(
hintText: 'Search your data',
contentPadding: EdgeInsets.all(15),
border: InputBorder.none),
controller: controller,
onChanged: (value) {
_alterfilter(value);
},
),
),
),
],
),
Expanded(
child: Container(
margin: const EdgeInsets.all(20),
child: ListView.builder(
scrollDirection: Axis.vertical,
shrinkWrap: true,
itemCount: _filtered.length,
itemBuilder: (context, index) {
if (array.length > 0) {
final x = _filtered[index];
final y = _filtered[index].id.toString();
return ListTile(
title: Text(y),
subtitle: Text(x.name),
);
}
},
),
))
],
),
),
));
}
}
Sorry mate if my english was very bad but tell me if you got confused