flutter-sport/lib/pages/social/social_detail_page.dart

import 'dart:ui';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/services.dart';
import 'package:flutter_easyrefresh/easy_refresh.dart';
import 'package:sport/bean/forum.dart';
import 'package:sport/bean/post.dart';
import 'package:sport/pages/social/post_detail_page.dart';
import 'package:sport/pages/social/post_page.dart';
import 'package:sport/pages/social/post_widget.dart';
import 'package:sport/provider/lib/provider_widget.dart';
import 'package:sport/provider/lib/view_state_lifecycle.dart';
import 'package:sport/provider/social_detail_model.dart';
import 'package:sport/router/navigator_util.dart';
import 'package:sport/services/api/resp.dart';
import 'package:sport/services/userid.dart';
import 'package:sport/widgets/appbar.dart';
import 'package:sport/widgets/error.dart';
import 'package:sport/widgets/loading.dart';
import 'package:sport/widgets/misc.dart';
import 'package:sport/widgets/persistent_header.dart';
import 'package:sport/widgets/space.dart';

class SocialDetailPage extends StatefulWidget {
  final Forum forum;
  final int index;

  SocialDetailPage(this.forum, {this.index});

  @override
  State<StatefulWidget> createState() => _PageState();
}

class _PageState extends ViewStateLifecycle<SocialDetailPage, SocialDetailModel>
    with TickerProviderStateMixin, UserId {
  ScrollController _controller;
  double _expandedHeight = 0;
  int _brightness = 0;

  TabController _tabController;
  final List<String> _tabs = ['热门', '关注', '最新', '精华', '我的'];
  Future<RespPage<Post>> _getPostListByOfficial;

  @override
  SocialDetailModel createModel() => SocialDetailModel(widget.index ?? 0);

  @override
  void initState() {
    super.initState();
    _getPostListByOfficial = model.api
        .getPostListByOfficial(forumId: widget.forum.forumId, limit: 3);
    _tabController = TabController(
        length: _tabs.length, initialIndex: widget.index ?? 0, vsync: this)
      ..addListener(() {
        if (_tabController.index.toDouble() == _tabController.animation.value) {
          model?.swtichTab(_tabController.index);
          _controller.animateTo(0,
              duration: Duration(milliseconds: 100), curve: Curves.ease);
        }
      });
    _controller = ScrollController()
      ..addListener(() {
        if (_controller.position.pixels >= _expandedHeight - 70) {
          if (_brightness == 0) {
            setState(() {
              _brightness = 1;
            });
          }
        } else {
          if (_brightness == 1) {
            setState(() {
              _brightness = 0;
            });
          }
        }
      });
  }

  @override
  void dispose() {
    super.dispose();
    _controller?.dispose();
    _tabController?.dispose();
    PaintingBinding.instance.imageCache.clear();
  }

  Widget _buildHeaderWidget() {
    return Stack(children: <Widget>[
      CachedNetworkImage(
        imageUrl: "${widget.forum.cover}",
        fit: BoxFit.cover,
        width: double.infinity,
        height: MediaQuery.of(context).size.width * 154.0 / 375 +
            MediaQuery.of(context).padding.top,
      ),
      BackdropFilter(
        filter: ImageFilter.blur(sigmaX: 30.0, sigmaY: 30.0),
        child: Center(
          child: Container(
            color: Colors.black.withOpacity(.3),
          ),
        ),
      ),
      Align(
        alignment: Alignment.center,
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: <Widget>[
            Padding(
              padding: const EdgeInsets.fromLTRB(12.0, 50, 12.0, 0),
              child: Row(
                mainAxisAlignment: MainAxisAlignment.start,
                children: <Widget>[
                  CircleAvatar(
                      backgroundImage:
                          CachedNetworkImageProvider("${widget.forum.cover}"),
                      radius: 30.0),
                  Space(
                    width: 12,
                  ),
                  Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: <Widget>[
                      Text(
                        "${widget.forum.name}",
                        style: Theme.of(context).textTheme.headline4,
                      ),
                      Space(
                        height: 10,
                      ),
                      Row(
                        children: <Widget>[
                          Image.asset(
                              "lib/assets/img/bbs_icon_reportnumber.png"),
                          Space(
                            width: 4,
                          ),
                          Text(
                            "帖子数：${widget.forum.subjectCount}",
                            style: Theme.of(context)
                                .textTheme
                                .subtitle2
                                .copyWith(color: Colors.white),
                          ),
                        ],
                      ),
                    ],
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
      Positioned(
        left: 0,
        right: 0,
        bottom: -1,
        child: Container(
          height: 10,
          decoration: BoxDecoration(
              borderRadius: BorderRadius.vertical(top: Radius.circular(10)),
              color: Colors.white),
        ),
      ),
    ]);
  }

  Color getColor(String tag) {
    if (tag == "榜单" || tag == "公告")
      return Theme.of(context).accentColor;
    else if (tag == "置顶") {
      return const Color(0xff5498FF);
    }
    return const Color(0xff00DC42);
  }

  Widget _buildHeaderListWidget() {
    return Container(
      decoration: BoxDecoration(
          color: Colors.white,
          borderRadius: BorderRadius.vertical(top: Radius.circular(10))),
      child: FutureBuilder<RespPage<Post>>(
        future: _getPostListByOfficial,
        builder:
            (BuildContext context, AsyncSnapshot<RespPage<Post>> snapshot) {
          if (snapshot.connectionState == ConnectionState.done &&
              snapshot.data?.pageResult?.results?.isNotEmpty == true) {
            return Column(children: <Widget>[
              Space(
                height: 5,
              ),
              Column(
                children: snapshot.data.pageResult.results
                    .map((e) => InkWell(
                        onTap: () {
                          Navigator.push(context,
                              MaterialPageRoute(builder: (context) {
                            return PostDetailPage(e, false,
                                snapshot.data?.pageResult?.results ?? []);
                          }));
                        },
                        child: Row(
                          children: <Widget>[
                            Container(
                                decoration: BoxDecoration(
                                    color: Colors.white,
                                    borderRadius:
                                        BorderRadius.all(Radius.circular(2)),
                                    border: Border.all(
                                      color: getColor(e.tags?.first),
                                      width: .5,
                                    )),
                                padding: EdgeInsets.symmetric(horizontal: 2),
                                margin: EdgeInsets.fromLTRB(12.0, 5, 6, 5),
                                child: Text(
                                  "${e.tags.first}",
                                  strutStyle: fixedLine,
                                  style: Theme.of(context)
                                      .textTheme
                                      .subtitle2
                                      .copyWith(color: getColor(e.tags?.first)),
                                )),
                            Expanded(
                              child: Text(
                                  "${e.title?.isNotEmpty == true ? e.title : e.content}",
                                  maxLines: 1,
                                  overflow: TextOverflow.ellipsis,
                                  style: Theme.of(context).textTheme.subtitle1),
                            )
                          ],
                        )))
                    .toList(),
              ),
              Space(
                height: 5,
              ),
              Divider()
            ]);
          }
          return Container();
        },
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    _expandedHeight = MediaQuery.of(context).size.width * 154.0 / 375;
    return Scaffold(
        backgroundColor: Colors.white,
        body: Stack(
          children: <Widget>[
            ProviderWidget<SocialDetailModel>(
              model: model,
              onModelReady: (model) => model.initData(),
              builder: (_, model, __) {
                return EasyRefresh.builder(
                    controller: model.refreshController,
                    enableControlFinishRefresh: true,
                    enableControlFinishLoad: true,
                    onRefresh: () => model.refresh(),
                    onLoad: model.isIdle ? () => model.loadMore() : null,
                    header: buildClassicalHeader(),
                    footer: buildClassicalFooter(),
                    builder: (context, physics, header, footer) {
                      return CustomScrollView(
                        controller: _controller,
                        physics: physics,
                        slivers: <Widget>[
                          SliverAppBar(
                            expandedHeight: _expandedHeight,
                            pinned: true,
                            elevation: 0,
                            iconTheme: IconThemeData(
                                color: _brightness == 0
                                    ? Colors.white
                                    : Colors.black),
                            brightness: _brightness == 0
                                ? Brightness.dark
                                : Brightness.light,
                            title: _brightness == 0
                                ? Text("")
                                : Text(
                                    "${widget.forum.name}",
                                    style: titleStyle,
                                  ),
                            backgroundColor: Colors.white,
                            flexibleSpace: FlexibleSpaceBar(
                              collapseMode: CollapseMode.pin,
                              background: _buildHeaderWidget(),
                            ),
                            leading: IconButton(
                              icon: Image.asset(
                                  "lib/assets/img/topbar_return${_brightness == 0 ? "_white" : ""}.png"),
                              onPressed: () {
                                Navigator.of(context).pop();
                              },
                            ),
                          ),
                          header,
                          SliverToBoxAdapter(
                            child: _buildHeaderListWidget(),
                          ),
                          SliverPersistentHeader(
                            delegate: PersistentHeader(
                                min: 34,
                                max: 34,
                                child: Container(
                                  color: Colors.white,
                                  padding: EdgeInsets.only(bottom: 5),
                                  child: TabBar(
                                    isScrollable: true,
                                    indicatorPadding:
                                        EdgeInsets.symmetric(horizontal: 8),
                                    indicatorWeight: 3,
                                    controller: _tabController,
                                    tabs:
                                        _tabs.map((e) => Tab(text: e)).toList(),
                                  ),
                                )),
                            pinned: true,
                          ),
                          if (model.isBusy)
                            SliverToBoxAdapter(
                              child: RequestLoadingWidget(),
                            ),
                          if (model.isEmpty)
                            SliverFillRemaining(
                              child: Center(
                                child: RequestErrorWidget(
                                  null,
                                  msg: "暂无帖子~",
                                  assets:
                                      RequestErrorWidget.ASSETS_NO_INVITATION,
                                ),
                              ),
                            ),
                          if (model.isIdle)
                            SliverList(
                              delegate: SliverChildBuilderDelegate(
                                (context, index) {
                                  Post post = model.list[index];
                                  return PostWidget(
                                      post, model, selfId == post.userId);
                                },
                                childCount: model.list.length,
                              ),
                            ),
                        ],
                      );
                    });
              },
            ),
            Positioned(
                right: 12.0,
                bottom: 12.0,
                child: GestureDetector(
                    onTap: () {
                      NavigatorUtil.goPage(
                          context,
                          (context) => PostPage(
                                widget.forum.forumId,
                                forum: widget.forum,
                              ));
                    },
                    child: Image.asset("lib/assets/img/bbs_icon_edit.png")))
          ],
        ));
  }
}