I’d like to make a map observable in my controller. But when I wrap the widget that’s using the observable map with Obx(), I get the runtime error that says “[Get] the improper use of a GetX has been detected. You should only use GetX or Obx for the specific widget that will be updated.”

But I thought I had used Obx for the specific widget to be updated.

class PaintingControllerX extends GetxController {
  final gridImages = <ui.Image?>[].obs;
}

class PaintingPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    var controller = Get.put<PaintingControllerX>(PaintingControllerX());
    return Scaffold(
      body: Obx(() => GridWidget(controller.gridImages)),  // ERROR
    );
  }
}

I saw in a different StackOverflow question (Obx widget throws an error) that the problem was resolved by calling the value property on the observed object. But RxMap.value is protected, I can’t use it here. I also noticed there’s a toList() method on RxList, but there’s no corresponding toMap() on RxMap.

How do I use a RxMap with Obx?