elcaribe/news-app/lib/ui/screens/CategoryScreen.dart

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:news/cubits/categoryCubit.dart';
import 'package:news/cubits/appLocalizationCubit.dart';
import 'package:news/data/models/CategoryModel.dart';
import 'package:news/ui/widgets/customTextLabel.dart';
import 'package:news/ui/widgets/errorContainerWidget.dart';
import 'package:news/ui/widgets/customAppBar.dart';
import 'package:news/ui/widgets/networkImage.dart';
import 'package:news/utils/ErrorMessageKeys.dart';
import 'package:news/utils/uiUtils.dart';
import 'package:news/app/routes.dart';

class CategoryScreen extends StatefulWidget {
  const CategoryScreen({super.key});

  @override
  CategoryScreenState createState() => CategoryScreenState();
}

class CategoryScreenState extends State<CategoryScreen> {
  late final ScrollController _categoryScrollController = ScrollController()..addListener(hasMoreCategoryScrollListener);

  void getCategory() {
    Future.delayed(Duration.zero, () {
      context.read<CategoryCubit>().getCategory(langId: context.read<AppLocalizationCubit>().state.id);
    });
  }

  @override
  void initState() {
    getCategory();
    super.initState();
  }

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

  void hasMoreCategoryScrollListener() {
    if (_categoryScrollController.offset >= _categoryScrollController.position.maxScrollExtent && !_categoryScrollController.position.outOfRange) {
      if (context.read<CategoryCubit>().hasMoreCategory()) {
        context.read<CategoryCubit>().getMoreCategory(langId: context.read<AppLocalizationCubit>().state.id);
      } else {}
    }
  }

  Widget _buildCategory() {
    return BlocBuilder<CategoryCubit, CategoryState>(
      builder: (context, state) {
        if (state is CategoryFetchSuccess) {
          return RefreshIndicator(
              onRefresh: () async {
                getCategory();
              },
              child: GridView.count(
                physics: const AlwaysScrollableScrollPhysics(),
                scrollDirection: Axis.vertical,
                padding: EdgeInsets.only(top: 15, bottom: MediaQuery.of(context).size.height / 10.0, left: 15, right: 15),
                crossAxisCount: 2,
                crossAxisSpacing: 10,
                mainAxisSpacing: 10,
                childAspectRatio: 0.92,
                shrinkWrap: true,
                controller: _categoryScrollController,
                children: List.generate(state.category.length, (index) {
                  return _buildCategoryContainer(
                      category: state.category[index], hasMore: state.hasMore, hasMoreCategoryFetchError: state.hasMoreFetchError, index: index, totalCurrentCategory: state.category.length);
                }),
              ));
        }
        if (state is CategoryFetchFailure) {
          return ErrorContainerWidget(
              errorMsg: (state.errorMessage.contains(ErrorMessageKeys.noInternet)) ? UiUtils.getTranslatedLabel(context, 'internetmsg') : state.errorMessage, onRetry: getCategory);
        }
        return const SizedBox.shrink();
      },
    );
  }

  _buildCategoryContainer({required CategoryModel category, required int index, required int totalCurrentCategory, required bool hasMoreCategoryFetchError, required bool hasMore}) {
    if (index == totalCurrentCategory - 1 && index != 0) {
      if (hasMore) {
        if (hasMoreCategoryFetchError) {
          return const SizedBox.shrink();
        } else {
          return Center(child: Padding(padding: const EdgeInsets.symmetric(horizontal: 15.0, vertical: 8.0), child: UiUtils.showCircularProgress(true, Theme.of(context).primaryColor)));
        }
      }
    }
    return GestureDetector(
      onTap: () {
        Navigator.of(context).pushNamed(Routes.subCat, arguments: {"catId": category.id, "catName": category.categoryName});
      },
      child: Card(
        color: UiUtils.getColorScheme(context).surface,
        child: Column(
          spacing: 10,
          mainAxisSize: MainAxisSize.min,
          children: [
            (category.image != null)
                ? Padding(
                    padding: const EdgeInsets.all(7.0),
                    child: ClipRRect(
                        borderRadius: BorderRadiusGeometry.circular(3), child: CustomNetworkImage(networkImageUrl: category.image!, height: 100, width: 140, isVideo: false, fit: BoxFit.cover)),
                  )
                : const SizedBox.shrink(),
            Padding(
                padding: const EdgeInsets.symmetric(horizontal: 5),
                child: CustomTextLabel(
                    text: category.categoryName!,
                    textStyle: TextStyle(fontWeight: FontWeight.w600, fontSize: 16, color: UiUtils.getColorScheme(context).primaryContainer),
                    textAlign: TextAlign.center,
                    maxLines: 2)),
          ],
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(appBar: CustomAppBar(height: 45, isBackBtn: false, label: 'categoryLbl', isConvertText: true), body: _buildCategory());
  }
}