1-) GetX kullanımı

import 'package:get/get.dart' hide Trans;

GenelSepetTipController tipController = new GenelSepetTipController();

flutter pub add get    kaynak : https://pub.dev/packages/get

NOT :

Widgeti Obx içine almayı unutma Obx(() => Text('clicks: ${controller.count}',)),

controller.dart

import 'package:get/get.dart';

class Controller extends GetxController {
  var count = 0.obs;
  void increment() {
    count++;
  }
}

getx_page.dart

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'controller.dart';

class GetXPage extends StatelessWidget {

  final controller = Get.put(Controller());

@override
void dispose() {
  Get.delete<Controller>();
  super.dispose();
}

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("counter")),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Obx(() => Text(
              'clicks: ${controller.count}',
            )),
            ElevatedButton(
              child: Text('Next Route'),
              onPressed: () {
                Get.to(Second());
              },
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.add),
        onPressed: (){
          controller.increment();
        },
      ),
    );
  }
}
class Second extends StatelessWidget {
  final Controller ctrl = Get.find();
  @override
  Widget build(context){
    return Scaffold(body: Center(child: Text("${ctrl.count}")));
  }
}

************************* DİĞER *************************

SaatGetx saatGetx = Get.put(SaatGetx());