Flutter GetX State Management

GetX State Management

Priority: P0 (CRITICAL)

Structure

lib/app/modules/home/
├── controllers/
│   └── home_controller.dart
├── bindings/
│   └── home_binding.dart
└── views/
    └── home_view.dart

Implementation Guidelines

• Controllers: Extend GetxController. Store logic and state variables here.
• Reactivity:
  • Use .obs for observable variables (e.g., final count = 0.obs;).
  • Wrap UI in Obx(() => ...) to listen for changes.
  • For simple state, use update() in controller and GetBuilder in UI.
• Dependency Injection:
  • Bindings: Use Bindings class to decouple DI from UI.
  • Lazy Load: Prefer Get.lazyPut(() => Controller()) in Bindings.
  • Lifecycle: Let GetX handle disposal. Avoid permanent: true.
• Hooks: Use onInit(), onReady(), onClose() instead of initState/dispose.
• Architecture: Use get_cli for modular MVVM (data, models, modules).

Anti-Patterns

• Ctx in Logic: Pass no BuildContext to controllers.
• Inline DI: Avoid Get.put() in widgets; use Bindings + Get.find.
• Fat Views: Keep views pure UI; delegate all logic to controller.

Code Example

class UserController extends GetxController {
  final name = "User".obs;
  void updateName(String val) => name.value = val;
}

class UserView extends GetView<UserController> {
  @override
  Widget build(ctx) => Scaffold(
    body: Obx(() => Text(controller.name.value)),
    floatingActionButton: FloatingActionButton(
      onPressed: () => controller.updateName("New"),
    ),
  );
}

Related Topics

getx-navigation | layer-based-clean-architecture | dependency-injection