Want to update a RxList type variable, but instead updated both variable with RxList type

[davey06]

hello, I have a GetxController class as below:

import 'package:get/get.dart';

class ProductPackageChildren {
  final int idProduct;
  final String productName;
  int qty;
  bool isSelected;

  ProductPackageChildren({
    this.idProduct,
    this.productName,
    this.qty,
    this.isSelected,
  });
}

class ProductPackageChildrenController extends GetxController {
  RxList<ProductPackageChildren> _productPackageChildren = <ProductPackageChildren>[].obs;
  RxList<ProductPackageChildren> tempProductPackageChildren = <ProductPackageChildren>[].obs;
  List<ProductPackageChildren> get productPackageChildren => _productPackageChildren;

  // addItem(ProductPackageChildren pItem) {
  //   _productPackageChildren.add(pItem);
  // }
  // updateItem(ProductPackageChildren pItem) {
  //   final index = _productPackageChildren.indexWhere((e) => e.idProduct == pItem.idProduct);
  //   if (index > -1) _productPackageChildren[index] = pItem;
  // }
  @override
  void onInit() {
    print('init');
    setDefault();
    ever(_productPackageChildren, (_) => printData());
    super.onInit();
  }

  setDefault() {
    _productPackageChildren.clear();
    for (int i = 0; i < 4; i++) {
      _productPackageChildren.add(ProductPackageChildren(idProduct: i, productName: 'Name$i', qty: i * i, isSelected: true));
    }
  }

  setData(List<ProductPackageChildren> data) {
    print('setData');
    _productPackageChildren.assignAll(data);
  }

  updateIsSelected(RxList<ProductPackageChildren> data, int pIdProduct, bool isSelected) {
    print(data.runtimeType);
    final index = data.indexWhere((e) => e.idProduct == pIdProduct);
    if (index > -1) data[index].isSelected = isSelected;
    update();
  }

  updateQty(RxList<ProductPackageChildren> data, int pIdProduct, pQty) {
    final index = data.indexWhere((e) => e.idProduct == pIdProduct);
    if (index > -1) data[index].qty = pQty;
  }

  setProductFromTemp() {
    print('SET DATA FROM TEMP');
    _productPackageChildren.assignAll(tempProductPackageChildren);
  }

  initTempData() {
    print('INIT  TEMP');
    tempProductPackageChildren = _productPackageChildren;
    printData();
    printTempData();
  }

  printData() {
    _productPackageChildren.forEach((e) {
      print('MAIN ${e.idProduct} ${e.productName} ${e.qty} ${e.isSelected}');
    });
  }

  printTempData() {
    tempProductPackageChildren.forEach((e) {
      print('TEMP ${e.idProduct} ${e.productName} ${e.qty} ${e.isSelected}');
    });
  }
}

view.dart

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

class TestBug extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return SafeArea(
      child: Scaffold(
        appBar: AppBar(
          title: Text('test bug'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              FlatButton(
                  onPressed: () {
                    Get.to(ContentView());
                  },
                  child: Text('Choose')),
              Expanded(
                child: GetBuilder(
                  init: ProductPackageChildrenController(),
                  builder: (ctrl) {
                    final selectedItem = ctrl.productPackageChildren.where((e) => e.isSelected == true).toList();
                    return ListView.builder(
                      itemCount: selectedItem.length,
                      itemBuilder: (ctx, i) {
                        final item = selectedItem[i];
                        return ListTile(
                          leading: Text('${item.qty} x'),
                          title: Text('${item.productName}'),
                        );
                      },
                    );
                  },
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class ContentView extends GetView<ProductPackageChildrenController> {
  ContentView();
  @override
  Widget build(BuildContext context) {
    controller.initTempData();

    return Scaffold(
      appBar: AppBar(),
      body: Column(
        children: [
          GetBuilder<ProductPackageChildrenController>(builder: (ctrl) {
            final data = ctrl.tempProductPackageChildren;
            return ListView.separated(
              shrinkWrap: true,
              physics: BouncingScrollPhysics(),
              itemCount: data.length,
              itemBuilder: (pCtx, pIndex) {
                final item = data[pIndex];
                return Row(
                  children: [
                    Expanded(
                        flex: 1,
                        child: TextFormField(
                          keyboardType: TextInputType.number,
                          decoration: const InputDecoration(
                            labelText: 'Jumlah',
                          ),
                          initialValue: item.qty.toString(),
                          onChanged: (value) {
                            controller.updateQty(data, item.idProduct, int.parse(value != "" ? value : "0"));
                          },
                        )),
                    SizedBox(width: 10),
                    Expanded(
                        flex: 5,
                        child: CheckboxListTile(
                          value: item.isSelected,
                          onChanged: (val) async {
                            controller.updateIsSelected(data, item.idProduct, val);
                          },
                          title: Text(item.productName),
                        ))
                  ],
                );
              },
              separatorBuilder: (pCtx, index) => Divider(),
            );
          }),
          FlatButton(
              onPressed: () {
                controller.setProductFromTemp();
                Get.back();
              },
              child: Text('Confirm'))
        ],
      ),
    );
  }
}

When I call UpdateSelected() both _productPackageChildren and tempProductPackageChildren list got updated as if it was linked by reference.

What I expected is only update the selected list (one of them) .

Thanks

[eduardoflorence]

If you want to refine a widget's update control with GetBuilder, you can assign them unique IDs:

GetBuilder<Controller>(
  id: 'text'
  init: Controller(),
  builder: (_) => Text(
    '${_.counter}', 
  ),
),

And update it this form:

update(['text']);

[davey06]

Thanks, I don't know that GetBuilder has an id. But this just fixes the view for me, the <List> in fact still changes. which is bad because I need the <List> only to be updated when the user clicks the confirm button.

my workaround is to add data manually to the list instead of using .addAll():

List<ProductPackageChildren> mainList = <ProductPackageChildren>[];
List<ProductPackageChildren> tempList = <ProductPackageChildren>[];

setDataMain() {
    print('setDataMAIN');
    mainList.clear();
    tempList.forEach((e) {
      mainList.add(ProductPackageChildren(idProduct: e.idProduct, productName: e.productName, qty: e.qty, isSelected: e.isSelected));
    });
    // mainList.addAll(tempList);
    update();
  }

 setDataTemp() {
    print('setDataTEMP');
    tempList.clear();
    mainList.forEach((e) {
      tempList.add(ProductPackageChildren(idProduct: e.idProduct, productName: e.productName, qty: e.qty, isSelected: e.isSelected));
    });
    // tempList.addAll(mainList);
    update();
  }

I dont know why if I use <List>.addAll() or <List>.assignAll() if RxList , when one list updated the other list is updated too.
(mainList and tempList in my case)

[thanhchelsea]

me too. Do you resole problem .... help me !!!

[davey06]

@thanhchelsea have you tried using unique id or my workaround? I have resolve it