Flutter GetX Re-Initialise GetX Controller Reset GetX Controller, Reset GetX Controller Values

Question

我正在学习自己的 Flutter GetX 并坚持了一点。实际上我想知道为什么当我再次访问该页面/对话框时不会调用 GetX Controlled 的 onInit 方法。

假设我有一个简单的TextField对话框，一个Listview，TextField用于搜索listview。当用户在文本字段中输入任何过滤键时， ListView 将被过滤。

这是示例对话框:

import 'package:flutter/material.dart';
import 'package:flutter_base_sample/util/apptheme/colors/app_colors.dart';
import 'package:flutter_base_sample/util/apptheme/styles/text_styles_util.dart';
import 'package:flutter_base_sample/util/commons/app_util.dart';
import 'package:flutter_base_sample/util/widgets/alert/controllers/country_finder_alert_controller.dart';
import 'package:flutter_base_sample/util/widgets/marquee/marquee_widget.dart';
import 'package:flutter_base_sample/util/widgets/textfields/app_text_field.dart';
import 'package:get/get.dart';

class SampleDialogWidget extends StatelessWidget {
  final CountryFinderAlertController controller = Get.put(CountryFinderAlertController(),permanent: true);

  @override
  Widget build(BuildContext context) {
    return Dialog(
      insetPadding: AppUtil.dialogPadding(context),
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(20),
      ),
      elevation: 0.0,
      backgroundColor: Colors.white,
      child: dialogContent(context),
    );
  }

  Widget dialogContent(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      mainAxisAlignment: MainAxisAlignment.start,
      mainAxisSize: MainAxisSize.max,
      children: [
        Text(
          "Hello Heading",
          style: TextStyleUtil.quickSandBold(context, fontSize: 16, color: Colors.blue),
          textAlign: TextAlign.center,
        ),
        SizedBox(
          height: 20,
        ),
        Expanded(
          child: SingleChildScrollView(
            child: Container(
              height: AppUtil.deviceHeight(context),
              padding: EdgeInsetsDirectional.all(20),
              child: Column(
                mainAxisSize: MainAxisSize.min,
                crossAxisAlignment: CrossAxisAlignment.stretch,
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Text("Hello Text1"),
                  SizedBox(
                    height: 10,
                  ),
                  getSearchField(context),
                  SizedBox(
                    height: 5,
                  ),
                  Expanded(
                    child: Obx(()=> getFavoritesListView(context)),
                  )
                ],
              ),
            ),
          ),
        ),
        SizedBox(
          height: 20,
        ),
        Container(
          margin: EdgeInsetsDirectional.only(start: 20,end: 20),
          child: ElevatedButton(
            onPressed: () {},
            style: ButtonStyle(
              overlayColor: MaterialStateProperty.all<Color>(Colors.red),
              // splashFactory: NoSplash.splashFactory,
              elevation: MaterialStateProperty.all(0.5),
              backgroundColor: MaterialStateProperty.resolveWith<Color>(
                (Set<MaterialState> states) {
                  if (states.contains(MaterialState.pressed)) {
                    return AppColors.instance.black.withOpacity(0.1);
                  } else {
                    return Colors.blue; // Use the component's default.
                  }
                },
              ),
            ),
            child: Text(
              "Hello Footer",
              style: TextStyleUtil.quickSandBold(context, fontSize: 16, color: Colors.yellow),
              textAlign: TextAlign.center,
            ),
          ),
        )
      ],
    );
  }

  Widget getFavoritesListView(BuildContext context) {
    if (controller.favoritesList.length > 0) {
      return ListView.separated(
        shrinkWrap: true,
        itemCount: controller.favoritesList.length,
        itemBuilder: (BuildContext context, int index) => _topupFavoriteContent(context, index),
        separatorBuilder: (context, index) {
          return Divider(
            indent: 15,
            endIndent: 15,
          );
        },
      );
    } else {
      return Center(
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          mainAxisAlignment: MainAxisAlignment.center,
          mainAxisSize: MainAxisSize.min,
          children: [
            Text(
              "No Data Found!",
              textAlign: TextAlign.center,
            ),
            SizedBox(
              height: 20,
            ),
          ],
        ),
      );
    }
  }

  Widget _topupFavoriteContent(BuildContext context, int index) {
    final item = controller.favoritesList[index];
    return InkWell(
        onTap: () {
          Get.back(result:item);
          // AppUtil.pop(context: context, valueToReturn: item);
        },
        child: getChildItems(context, index));
  }

  Widget getChildItems(BuildContext context, int index) {
    return Directionality(textDirection: TextDirection.ltr, child: getContactNumberAndNameHolder(context, index));
  }

  Widget getContactNumberAndNameHolder(BuildContext context, int index) {
    final item = controller.favoritesList[index];
    return Container(
      padding: EdgeInsetsDirectional.only(start: 20, end: 20, top: 20, bottom: 10),
      child: Column(
        children: [
          Row(
            // crossAxisAlignment: CrossAxisAlignment.start,
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Flexible(
                child: Align(
                  alignment: AlignmentDirectional.centerStart,
                  child: Text(
                    item.name ?? "",
                    style: TextStyleUtil.quickSandBold(context, fontSize: 15, color: AppColors.instance.black),
                  ),
                ),
              ),
              SizedBox(
                width: 5,
              ),
              Container(),
              Align(
                alignment: AlignmentDirectional.centerEnd,
                child: MarqueeWidget(
                  child: Text(
                    item.dialCode ?? "",
                    style: TextStyleUtil.quickSandBold(context, fontSize: 15, color: Colors.blue),
                  ),
                ),
              ),
            ],
          )
        ],
      ),
    );
  }

  Widget getSearchField(
    BuildContext context,
  ) {
    return Container(
        margin: EdgeInsetsDirectional.only(start: 20, end: 20, top: 20),
        child: Row(
          children: [
            Expanded(
              child: AppTextField(
                onChanged: (String text) {
                  controller.performSearchOnForFavoriteContact(text);
                },
                isPasswordField: false,
                keyboardType: TextInputType.text,
                suffixIconClickCallBack: () {},
              ),
            )
          ],
        ));
  }
}

这里是 GetX Controller :

class CountryFinderAlertController extends GetxController {
  TextEditingController countrySearchFieldEditController = TextEditingController();
  RxList<CountryHelperModel> favoritesList;
  RxList<CountryHelperModel> originalList;

  @override
  void onInit() {
    super.onInit();
    debugPrint("Hello222");
    favoritesList = <CountryHelperModel>[].obs;
    originalList = <CountryHelperModel>[].obs;
  }

  @override
  void onReady() {
    super.onReady();
    debugPrint("Hello111");
    originalList.addAll(JSONHelperUtil.getCountries());
    addAllCountries();
  }

  @override
  void dispose() {
    super.dispose();
    countrySearchFieldEditController.dispose();
  }

  @override
  void onClose() {
    super.onClose();
  }

  void performSearchOnForFavoriteContact(String filterKey) {
    if (filterKey != null && filterKey.isNotEmpty) {
      List<CountryHelperModel> filteredFavoritesList = [];

      debugPrint("filterKey" + filterKey);
      originalList.forEach((element) {
        if (element.name.toLowerCase().contains(filterKey.toLowerCase()) ||
            element.countryCode.toLowerCase().contains(filterKey.toLowerCase()) ||
            element.dialCode.toLowerCase().contains(filterKey.toLowerCase())) {
          filteredFavoritesList.add(element);
        }
      });

      if (filteredFavoritesList.isNotEmpty) {
        favoritesList.clear();
        favoritesList.addAll(filteredFavoritesList);
      } else {
        favoritesList.clear();
      }
    } else {
      //reset the list
      addAllCountries();
    }
  }

  void addAllCountries() {
    favoritesList.clear();
    favoritesList.addAll(originalList);
  }
}

所以我想要的是每次打开此对话框时加载新数据。目前，如果用户搜索任何国家并关闭对话框，然后如果重新打开它，用户将看到旧的搜索结果。

简单来说，GetX Controller 如何被重置/销毁或重新初始化!

提前致谢

Answer 1

我相信是因为 ,permanent: true
试着把它排除在外。