How to change variable with getx? - flutter

Question

As in the codes I mentioned below, my question is actually simple, but I couldn't find a simple answer on the internet. All the sources I found are going through the same example. There is no simple explanation, but there is good stackoverflow. Let me ask my question without further ado.
I can specify a variable in getx and print that variable on other pages. What I want to do now is I want to change the getx variable in the main file, how can I do that?
I'm posting the wrong version of the code I want to do below for you to understand.
code in getx folder
class numcontroller extends GetxController {
var derece = 20.obs;
}
code is second page
numcontroller deneme = Get.put(numcontroller());
Container(
margin: const EdgeInsets.fromLTRB(27, 10, 0, 0),
child: Row(
children: [
Container(
margin: const EdgeInsets.fromLTRB(5, 0, 0, 0),
child: Text('${deneme.derece.value}',
style: const TextStyle(
fontSize: 45,
fontFamily: 'YesevaOne',
color: Color(0xFF2d4b70)),
),
),
The code I want to run in main.dart
derece = 20
or
derece = 30
When I change the degree manually on main.dart, I want it to change on the second page as well.
EDİTİNG
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:teemapp4/Controller/switch_controller.dart';
import 'routes/app_pages.dart';
import 'routes/app_routes.dart';
import 'themes/app_theme.dart';
//0xFF2d4b70
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return GetMaterialApp(
initialRoute: AppRoutes.DASHBOARD,
getPages: AppPages.list,
debugShowCheckedModeBanner: false,
theme: AppTheme.light,
darkTheme: AppTheme.dark,
themeMode: ThemeMode.system,
);
}
}
this is my main.dart code but i am using a bottombar i made with getx. I'm looking for how to change the data in that file through this code.

Answer 1

I don't think So you need to update your main.dart file.
You can add a button on your first page to update values like:
firstPage.dart
class FirstPage extends StatelessWidget {
FirstPage({Key? key}) : super(key: key);
NumController numController = Get.put(NumController());
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Column(
children: [
ElevatedButton(
onPressed: () {
numController.updateDerece(30);
},
child: Text(
"Update Value",
),
),
ElevatedButton(
onPressed: () {
Get.to(() => SecondPage());
},
child: Text("Go To Second Screen"),
),
],
),
),
);
}
}
secondPage.dart
class SecondPage extends StatelessWidget {
SecondPage({Key? key}) : super(key: key);
NumController numController = Get.find<NumController>();
#override
Widget build(BuildContext context) {
return Container(
child: Text(
numController.derece.toString(),
),
);
}
}
Or You can directly update the value on your second page like:
secondPage.dart
class SecondPage extends StatelessWidget {
SecondPage({Key? key}) : super(key: key);
NumController numController = Get.put(NumController());
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Column(
children: [
ElevatedButton(
onPressed: () {
//Any Number You can pass in Function
numController.updateDerece(30);
},
child: Text(
"Update Value",
),
),
Obx(
() => Container(
child: Text(
numController.derece.toString(),
),
),
),
],
),
),
);
}
}
numController.dart
import 'package:get/get.dart';
class NumController extends GetxController {
var _derece = 20.obs;
int get derece => _derece.value;
void updateDerece(int value) {
_derece.value = value;
}
}

Answer 2

Try using this way. And update your derece variable value using updateDerece method.
var _derece = 20.obs;
double get derece => _derece.value;
void updateDerece(double value) {
_derece.value = value;
}
////
Obx(() {
return Container(
margin: const EdgeInsets.fromLTRB(27, 10, 0, 0),
child: Row(
children: [
Container(
margin: const EdgeInsets.fromLTRB(5, 0, 0, 0),
child: Text(
'${deneme.derece}',
style: const TextStyle(
fontSize: 45,
fontFamily: 'YesevaOne',
color: Color(0xFF2d4b70)),
),
),
],
),
);
})