Flutter change theme and icon of a iconbutton with Getx - flutter

Question

I have the following example to change from dark to light mode using Getx. So far it is working. But i would also that the IconButton who change the Theme, would also change is own icon.
What im doing wrong?
import 'package:flutter/material.dart';
import 'package:get/get.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return GetMaterialApp(
debugShowCheckedModeBanner: false,
title: 'Change Theme',
darkTheme: ThemeData.dark(),
themeMode: ThemeMode.system,
home: HomeScreen(),
);
}
}
// Home Screen
class HomeScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
var selected = true;
return Scaffold(
appBar: AppBar(
title: Text('Change Theme'),
actions: [
IconButton(
icon: Icon(
selected ? Icons.dark_mode : Icons.light_mode,
),
onPressed: () {
Get.isDarkMode
? Get.changeTheme(ThemeData.light())
: Get.changeTheme(ThemeData.dark());
})
],
),
);
}
}

Answer 1

You need to wrap the icon in a GetX widget that rebuilds based on a variable that lives in a GetX class.
Create a Getx class with a function that changes the theme based on the value of the local boolean.
class ThemeController extends GetxController {
bool isDarkMode = true;
void toggleDarkMode() {
isDarkMode = !isDarkMode;
if (isDarkMode) {
Get.changeTheme(ThemeData.dark());
} else {
Get.changeTheme(ThemeData.light());
}
update();
}
Then wrap your icon in a GetBuilder<ThemeController>
class HomeScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
Get.put(ThemeController());
return Scaffold(
appBar: AppBar(
title: Text('Change Theme'),
actions: [
GetBuilder<ThemeController>(
builder: (controller) => IconButton(
icon: Icon(
controller.isDarkMode ? Icons.dark_mode : Icons.light_mode,
),
onPressed: () => controller.toggleDarkMode()
],
),
);
}
}
My VsCode is outta commission because I'm traveling with painfully slow internet and I'm in the middle of a multi hour flutter upgrade. So there might be some syntax or minor formatting errors but besides that this should work.