flutter_wisetronic/lib/widgets/desktop/desktop_blog.dart

import 'package:flutter/material.dart';
import 'package:flutter_spinkit/flutter_spinkit.dart';
import 'package:pull_to_refresh/pull_to_refresh.dart';

import '../../constants.dart';
import '../../events/eventbus.dart';
import '../../events/events.dart';
import '../../generated/l10n.dart';
import '../../models/address.dart';
import '../../models/blog.dart';
import '../../models/ticket.dart';
import '../../pages/edit_address.dart';
import '../../routes.dart';
import '../../store/actions.dart';
import '../../store/store.dart';
import '../../utils/http_util.dart';
import '../../utils/utils.dart';
import '../../widgets/general/bottom_nav.dart';
import '../../widgets/general/breadcrumbs.dart';
import '../../widgets/general/navigationbar.dart';
import '../../utils/util_web.dart' if (dart.library.io) '../../utils/util_io.dart';

class DesktopBlog extends StatefulWidget {
  final int businessId;
  const DesktopBlog({Key key, this.businessId}) : super(key: key);

  @override
  State<StatefulWidget> createState() {
    return DesktopBlogState();
  }

}

class DesktopBlogState extends State<DesktopBlog> {
  List<Blog> blogs;

  double division = 2;

  int _page = 1;
  int _pageCount = 1;

  bool _isLoading = false;
  bool _loadingFinish = false;

  RefreshController _refreshController = RefreshController(initialRefresh: true);

  void _onRefresh() {
    _page = 1;
    if (blogs != null) {
      blogs.clear();
    } else {
      blogs = [];
    }
    _refreshController.resetNoData();
    loadBlogs(true);
  }

  void _onLoadMore() {
    // if failed,use loadFailed(),if no data return,use LoadNodata()
    if (_pageCount > _page) {
      _page += 1;
      loadBlogs(false);
    } else {
      _refreshController.loadNoData();
    }
  }

  double sideSpace = 0;
  double mainSpace = 1200;

  @override
  Widget build(BuildContext context) {
    store.dispatch(UpdateContext(context));

    if (MediaQuery.of(context).size.width <= 1200) {
      mainSpace = MediaQuery.of(context).size.width;
      sideSpace = 0;
    } else {
      mainSpace = 1200;
      sideSpace = (MediaQuery.of(context).size.width - 1200) / 2;
    }

    BuildContext mainContext = context;

    return Scaffold(
      appBar: NavigationBar(
        title: S.of(context).blog,
        back: true,
        breadCrumbs: [
          BreadCrumb(S.of(context).blog, null),
        ],
        breadCrumbHeight: Constants.BREADCRUMB_HEIGHT,
      ),
      body: SmartRefresher(
        enablePullDown: true,
        enablePullUp: true,
        header: WaterDropHeader(),
        footer: CustomFooter(
          builder: (BuildContext context, LoadStatus mode){
            Widget footer;
            if(mode == LoadStatus.idle) {
              footer = Text(S.of(context).pull_up_to_load_more);
            } else if (mode == LoadStatus.loading) {
              footer = CircularProgressIndicator();
            } else if (mode == LoadStatus.failed) {
              footer = Text(S.of(context).load_failed_retry);
            } else if (mode == LoadStatus.canLoading) {
              footer = Text(S.of(context).release_to_load_more);
            } else if (mode == LoadStatus.noMore) {
              footer = Text(S.of(context).no_more_record);
            } else {
              footer = Text('...');
            }
            return Container(
              height: 55.0,
              child: Center(child: footer,),
            );
          },
        ),
        controller: _refreshController,
        onRefresh: _onRefresh,
        onLoading: _onLoadMore,
        child: _buildBody(),
      ),
      bottomNavigationBar: BottomNav(),
    );
  }

  Widget _buildBody() {
    if (blogs == null) {
      return SizedBox.shrink();
    }
    Row row = Row(
      mainAxisAlignment: MainAxisAlignment.start,
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Container(
          width: sideSpace,
        ),
        Container(
          width: mainSpace,
          padding: EdgeInsets.only(
            top: 12.0,
            bottom: 16.0,
            left: 8.0,
            right: 8.0,
          ),
          child: blogs == null ? Text('') :
          (blogs.length > 0 ?
          Wrap(
            children: blogs.map((a) => GestureDetector(
              child: _getBlog(a),
              onTap: () {
                Routes.router.navigateTo(context, '/view-blog/${a.id}');
              },
            )).toList(),
          ) :
          Center(
            child: Text(S.of(context).no_blog_yet),
          )),
        ),
        Container(
          width: sideSpace,
        ),
      ],
    );
    return SingleChildScrollView(
      child: row,
    );
  }

  Widget _getBlog(Blog blog) {
    return Container(
      width: (mainSpace - 16.0) / division,
      padding: EdgeInsets.symmetric(vertical: 8.0, horizontal: 8.0),
      child: Container(
        padding: EdgeInsets.only(top: 20.0, bottom: 20.0, left: 16.0, right: 16.0,),
        decoration: BoxDecoration(
          border: Border(
            bottom: BorderSide(
              color: Colors.black12,
              width: 0.6,
            ),
            top: BorderSide(
              color: Colors.black12,
              width: 0.6,
            ),
            left: BorderSide(
              color: Colors.black12,
              width: 0.6,
            ),
            right: BorderSide(
              color: Colors.black12,
              width: 0.6,
            ),
          ),
          borderRadius: BorderRadius.all(Radius.circular(10.0)),
        ),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.start,
          children: <Widget>[
            (blog.thumbUrl != null) ?
            Container(
              padding: EdgeInsets.only(right: 10.0),
              child: Util.showImage(
                'https:${blog.thumbUrl}',
                width: 80,
                height: 80,
              ),
            ) : SizedBox.shrink(),
            Expanded(
              child: Column(
                mainAxisAlignment: MainAxisAlignment.start,
                crossAxisAlignment: CrossAxisAlignment.start,
                children: <Widget>[
                  Container(
                    child: Text(
                      blog.title,
                      style: TextStyle(
                        fontSize: 19.0,
                      ),
                      overflow: TextOverflow.ellipsis,
                    ),
                  ),
                  Container(
                    child: Text(
                      Utils.utcDatetimeStringToLocalDatetimeString(context, blog.createdAt,),
                      style: TextStyle(
                        fontSize: 13.0,
                        color: Colors.grey,
                      ),
                    ),
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  @override
  void dispose() {
    _refreshController?.dispose();
    super.dispose();
  }

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

    eventBus.on<OnTicketsUpdated>().listen((event) {
      if (mounted) {
        setState(() {
          blogs = null;
        });
      }
      _refreshController.requestRefresh();
    });
  }

  void loadBlogs(bool isRefresh) {
    _loadingFinish = false;
    HttpUtil.httpGet(
        'v1/blogs',
        businessId: widget.businessId,
        queryParameters: {
          'page': _page.toString(),
          'size': Constants.BLOG_PER_PAGE_DESKTOP.toString()
        }
    ).then((value) {
      if (mounted) {
        if (isRefresh) {
          _refreshController.refreshCompleted();
        } else {
          _refreshController.loadComplete();
        }

        if (int.parse(value['currentPage'].toString()) >= int.parse(value['pageCount'].toString())) {
          _loadingFinish = true;
        }
        if (_loadingFinish) {
          _refreshController.loadNoData();
        }
        _page = int.parse(value['currentPage'].toString());
        _pageCount = int.parse(value['pageCount'].toString());

        setState(() {
          if (blogs == null) {
            blogs = [];
          }
          blogs.addAll((value['blogs'] as List).map((e) => Blog.fromJson(e)).toList());
        });
      }
    }).catchError((error) {
      if (mounted) {
        if (isRefresh) {
          _refreshController.refreshFailed();
        } else {
          _refreshController.loadFailed();
        }
        _isLoading = false;
        Utils.showMessageDialog(context, error, onOk: () {
          Navigator.of(context).pop();
          Navigator.of(context).pop();
        });
      }
    });
  }

}