How to filter's by id in Dart? Not searching bar - flutter

Question

guys, I am trying to make filter by using id's of item. I have researched a lot, but I think I am missing something obvious. So as I said i need to make a filtration, I have API where two different models Transport and Marshes. Each clasess contains id of bus, tram, subway. For the bus id = 1, for tram = 2, for sunbway id = 3 and for each of these separate id's API contains the 3 separate list of bus' numbers, tram's numbers and subway's train numbers.
I create two models and two screen:
The models
class TransportType {
TransportType({
this.ttId,
this.ttTitle,
this.ttNote,
});
final int ttId;
final String ttTitle;
String ttNote;
}
Also I also clearly indicated that I need the ID of the route in the link from the API. Now it look like so:
For Marshes it is:
Future<List<Marshes>> fetchMarshes() async {
final response = await http.post(
Uri.parse(
'http:/getMarshes.php?fmt=json&tt_id'),
body: {'tt_id': '1'}, headers: <String, String>{'authorization': basicAuth}, );
For fetching Transport model it looks like this:
Future<List<TransportType>> fetchTranspotes() async {
var response = await http.get(
Uri.parse(
'http://getTransportTypes.php?fmt=json'),
headers: <String, String>{'authorization': basicAuth});
var jsonResponse = convert.jsonDecode(response.body) as List;
return jsonResponse
.map((transport) => TransportType.fromJson(transport))
.toList();
}
For fetching the both list: List of Transport types and List of Numbers I am using FutureBuilder:
The srceen one for Transport Types looks like so:
body: FutureBuilder<List<TransportType>>(
future: futureTransposrt,
builder: (context, snapshot) {
if(snapshot.hasData){
return ListView.builder(
itemCount: snapshot.data.length,
itemBuilder: (builder, index){
TransportType project = snapshot.data[index];
return ListTile(
title: Text(project.ttId.toString()),
onTap: (){
Navigator.of(context).pushAndRemoveUntil(MaterialPageRoute(builder: (context)=>MarshId(ttId: 1,)), (route) => false);
},
In the conctructor of MarshId I put the values I want, so the second sreen also has the same conctructor and it looks like this:
class MarshId extends StatefulWidget {
final int ttId;
const MarshId({Key key, this.ttId}) : super(key: key);
#override
_MarshIdState createState() => _MarshIdState();
}
So my qiestions is pretty dumb: What am I doing wrong? I did everything as docs say and I reserched here on SO, but it dosen't work and I copmpletly don't understand what I am doing wrong. I also used this expression as here reccomend but now it seems like it is not work:marshes = marshes.where((marsh) => marsh.ttId == ttId).toList(); I understand this task: I need to filter the data by category and when the user clicks on certain transport type, for example, "bus", he gets to the screen where there is only a list of bus numbers. But I can't figure out what exactly I am doing wrong when I write filtering.
I really appreciate your help, guys!

Answer 1

you can pass id to other page by using constructor in your ListBus() class the you simply use where like this
ie. let's say you parameter name is ttId;
then your filter will be
marshes = marshes.where((marsh) => marsh.ttId == ttId).toList();