getting query parameter on initial route flutter - flutter

Question

I'm working on a flutter application mainly for the web, and I'm unable to add/get the query
parameter from the URL, the query parameter will contain an id, and this id should be used inside the app
this my route setup on my app state:
return MaterialApp(navigatorKey: key, initialRoute: '/main',
routes: {
// When navigating to the "/" route, build the FirstScreen widget.
'/main': (context) => Map_View(),
// When navigating to the "/second" route, build the SecondScreen widget.
'/second': (context) => TaskClosed(),
},onGenerateRoute: RouteGenerator.generateRoute,);
}
class RouteGenerator{
static Route<dynamic> generateRoute(RouteSettings settings){
final args = settings.arguments;
print(args);
var routingData = settings.name;
}}
the settings.arguments are always null
so what should I pass to initialRoute to make it accept arguments on the first screen
for example, the calling URL should be like this:
https:example.com/main?123
so how to get this parameter from the URL

Answer 1

I tried this code:
class RouteGenerator {
static Route<dynamic> generateRoute(RouteSettings settings) {
String? route;
Map? queryParameters;
if (settings.name != null) {
var uriData = Uri.parse(settings.name!);
route = uriData.path;
queryParameters = uriData.queryParameters;
}
var message =
'generateRoute: Route $route, QueryParameters $queryParameters';
print(message);
return MaterialPageRoute(
builder: (context) {
return MyHomePage(title: message);
},
settings: settings,
);
}
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Test App',
theme: ThemeData(
primarySwatch: Colors.blue,
),
initialRoute: '/main',
routes: {
// '/': (context) {
// print('route: /');
// return MyHomePage(title: 'Home');
// },
'/main': (context) {
print('route: /main');
return MyHomePage(title: 'route: Main');
},
'/second': (context) {
print('route: /second');
return MyHomePage(title: 'route: Second');
},
},
onGenerateRoute: RouteGenerator.generateRoute,
);
}
}
When I run the app with the URL http://localhost:55260/#/main?123, I get this output:
generateRoute: Route /, QueryParameters {}
generateRoute: Route /main, QueryParameters {123: }
The screen is displayed for /main and the URL is displayed correctly.

Answer 2

Sorry, I misunderstand the scenario. Here is my suggest
remove routes
return MaterialApp(navigatorKey: key, initialRoute: '/main',
//routes: {
// When navigating to the "/" route, build the FirstScreen widget.
//'/main': (context) => Map_View(),
// When navigating to the "/second" route, build the SecondScreen widget.
//'/second': (context) => TaskClosed(),
// },
onGenerateRoute: RouteGenerator.generateRoute,);
}
And change like
class RouteGenerator {
static Route<dynamic> generateRoute(RouteSettings settings) {
final args = settings.arguments;
print(args);
var routingData = settings.name;
switch (routingData) {
case "/main":
return MaterialPageRoute(
builder: (context) {
return Map_View();
},
settings: settings,
);
break;
case "/second":
return MaterialPageRoute(
builder: (context) {
return TaskClosed();
},
settings: settings,
);
break;
default:
return MaterialPageRoute(
builder: (context) {
return YouUnKnowPage();
},
settings: settings,
);
}
}
}
when you call Navigator.of(context).pushNamed("/main",arguments:"123");
It will move to TaskClosed and print 123 in the console
Furthermore, if you directly type the link like https:example.com/main?123
It will lead to YouUnKnowPage instead of Map_View and the arguments will be null. Try to use Navigator.of(context).pushNamed("/main",arguments:"123");
If you insist on directly type the link, you can try this
class RouteGenerator {
static Route<dynamic> generateRoute(RouteSettings settings) {
String routingData;
var arguments;
if (settings.name != null) {
routingData = settings.name;
}
final args = settings.arguments;
if (args != null) {
arguments = args;
} else {
Uri settingsUri = Uri.parse(settings.name);
if (settingsUri.hasQuery) {
arguments = "${settingsUri.queryParameters}";
}
if (settingsUri.pathSegments.length > 1) {
routingData =
"/" + settingsUri.pathSegments[settingsUri.pathSegments.length - 1];
}
}
if (arguments != null) {
print(arguments);
}
switch (routingData) {
case "/main":
return MaterialPageRoute(
builder: (context) {
return Map_View();
},
settings: settings,
);
break;
case "/second":
return MaterialPageRoute(
builder: (context) {
return TaskClosed();
},
settings: settings,
);
break;
default:
return MaterialPageRoute(
builder: (context) {
return YouUnKnowPage();
},
settings: settings,
);
}
}
}
Now it will move to TaskClosed and print {123:} in the console