flutter-freaccess-hub/lib/shared/mixins/pegeable_mixin.dart

import 'package:flutter/material.dart';
import 'package:hub/flutter_flow/index.dart';
import 'package:hub/shared/utils/limited_text_size.dart';
import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';

extension PagedListViewExtension<PageKeyType, ItemType>
    on PagedSliverList<PageKeyType, ItemType> {}

typedef PaginatedListViewHeaderBuilder<T> = Widget Function<T>(
    Future<List<T?>> Function() gen);
typedef PaginatedListViewBodyBuilder<T> = Widget Function(BuildContext, T, int);

mixin Pageable<T extends StatefulWidget> on State<T> {
  Expanded buildPaginatedListView<PageKeyType, BodyType, HeaderType>(
      String noDataFound,
      PagingController<PageKeyType, BodyType> pg,
      Future<List<HeaderType?>> Function() headerItems,
      PaginatedListViewHeaderBuilder<BodyType> headerBuilder,
      PaginatedListViewBodyBuilder<BodyType> bodyBuilder) {
    final theme = FlutterFlowTheme.of(context);
    return Expanded(
      child: RefreshIndicator(
        backgroundColor: theme.primaryBackground,
        color: theme.primary,
        onRefresh: () async => pg.refresh(),
        child: PagedListView<PageKeyType, BodyType>(
          pagingController: pg,
          builderDelegate: PagedChildBuilderDelegate<BodyType>(
            animateTransitions: true,
            itemBuilder: (context, item, int index) {
              return Column(children: [
                if (index == 0) headerBuilder(headerItems),
                bodyBuilder(context, item, index),
              ]);
            },
            newPageProgressIndicatorBuilder: (context) =>
                buildLoadingIndicator(context),
            firstPageProgressIndicatorBuilder: (context) =>
                buildLoadingIndicator(context),
            noItemsFoundIndicatorBuilder: (context) =>
                buildNoDataFound<HeaderType>(
                    context, noDataFound, headerItems, headerBuilder),
            firstPageErrorIndicatorBuilder: (context) => const Placeholder(),
            newPageErrorIndicatorBuilder: (context) => const Placeholder(),
          ),
        ),
      ),
    );
  }

  Future<void> showError(PagingStatus status, PagingController pg) async {
    if (status == PagingStatus.subsequentPageError) {
      final message = FFLocalizations.of(context).getVariableText(
        enText: 'Something went wrong while fetching a new page.',
        ptText: 'Algo deu errado ao buscar uma nova página.',
      );
      final retry = FFLocalizations.of(context).getVariableText(
        enText: 'Retry',
        ptText: 'Recarregar',
      );

      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text(message),
          action: SnackBarAction(
            label: retry,
            onPressed: () => pg.retryLastFailedRequest(),
          ),
        ),
      );
    }
  }

  Future<void> fetchPage({
    required Future<(bool, dynamic)> Function() dataProvider,
    required void Function(dynamic data) onDataAvailable,
    required void Function() onDataUnavailable,
    required void Function(Object error, StackTrace stackTrace) onFetchError,
  }) async {
    try {
      final (bool isDataAvailable, dynamic data) = await dataProvider();
      if (isDataAvailable) {
        onDataAvailable(data);
      } else {
        onDataUnavailable();
      }
    } catch (error, stackTrace) {
      onFetchError(error, stackTrace);
    }
  }

  void showNoMoreDataSnackBar(BuildContext context) {
    final message = FFLocalizations.of(context).getVariableText(
      ptText: "Não há mais dados.",
      enText: "No more data.",
    );

    showSnackbar(context, message, true);
  }

  Widget buildNoDataFound<T>(
    BuildContext context,
    String title,
    Future<List<T?>> Function() items,
    Widget Function<T>(Future<List<T?>> Function() items) headerBuilder,
  ) {
    final headerFontSize = LimitedFontSizeUtil.getHeaderFontSize(context);
    // final bodyFontSize = LimitedFontSizeUtil.getBodyFontSize(context);
    return Column(
      children: [
        headerBuilder(items),
        Expanded(
          child: Center(
            child: Text(
              title,
              style: TextStyle(
                fontFamily: 'Nunito',
                fontSize: headerFontSize,
              ),
            ),
          ),
        ),
      ],
    );
  }

  Widget buildLoadingIndicator(BuildContext context) {
    print('Loading');
    return Container(
      padding: const EdgeInsets.symmetric(vertical: 15),
      child: Center(
        child: CircularProgressIndicator(
          valueColor: AlwaysStoppedAnimation<Color>(
            FlutterFlowTheme.of(context).primary,
          ),
        ),
      ),
    );
  }
}