twong-flutter/lib/pages/tabs/home.dart

import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
import 'package:provider/provider.dart';
import 'package:flutter_swiper/flutter_swiper.dart';
import 'package:flutter_easyrefresh/easy_refresh.dart';
import 'package:color_thief_flutter/color_thief_flutter.dart';
import 'package:cached_network_image/cached_network_image.dart';

import 'package:twong/api/index.dart';
import 'package:twong/pages/tabs.dart';
import 'package:twong/utils/index.dart';
import 'package:twong/router/index.dart';
import 'package:twong/config/style.dart';
import 'package:twong/models/index.dart';
import 'package:twong/widgets/fsuper.dart';
import 'package:twong/providers/home.dart';
import 'package:twong/providers/message.dart';
import 'package:twong/utils/image_utils.dart';
import 'package:twong/widgets/search_bar.dart';
import 'package:twong/widgets/sliver_bar.dart';
import 'package:twong/widgets/product_item.dart';

class HomePage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return _HomePageState();
  }
}

class _HomePageState extends State<HomePage> {
  Home _data;
  int _currentPage = 1;
  bool _checkColor = true;
  Color headerColor = Colors.red;
  ScrollController _controller = ScrollController();

  @override
  initState() {
    super.initState();
    loadData();
    _controller.addListener(_onScroll);
  }

  loadData() async {
    _data = Cache.get(SaveKey.home);
    if(Cache.user == null) {
      Network.inst.autoLogin().then((res) {
        getData();
      });
    } else {
      getData();
    }
  }

  getData() {
    Network.inst.getIndex().then((res) {
      setState(() {
        _data = Provider
            .of<HomeModel>(context, listen: false)
            .data;
        headerColor = Provider
            .of<HomeModel>(context, listen: false)
            .headerColor;
      });
      Cache.set(SaveKey.home, _data);
    });
  }

  _onSwipeChange(int index) async {
    if (!_checkColor) return;
    var image = CachedNetworkImageProvider(_data.banner[index].pic);
    getColorFromImage(await getImageFromProvider(image)).then((color) {
      var colors = Color.fromARGB(255, color[0], color[1], color[2]);
      var hsl = HSLColor.fromColor(colors);
      // 降低颜色亮度
      colors = hsl.withLightness(hsl.lightness * 3 / 4).toColor();
      setState(() {
        headerColor = colors;
      });
      // Provider.of<HomeModel>(context, listen: false).setHeaderColor(colors);
    }).catchError((err) {
      Log.d(err);
    });
  }

  Widget _buildSlider (BuildContext context, int index) {
    var banner = _data.banner[index];
    return CachedNetworkImage(
      fit: BoxFit.cover,
      imageUrl: banner.pic,
      imageBuilder: (BuildContext context, ImageProvider<dynamic> provider) {
        return GestureDetector(
          onTap: () {
            var id = banner.url.split("/")[2];
            Navigator.pushNamed(context, RouteNames.productDetails, arguments: id);
          },
          child: Container(
            decoration: BoxDecoration(
              borderRadius: BorderRadius.circular(4.px),
              image: DecorationImage(
                  image: provider,
                  fit: BoxFit.cover
              ),
            ),
          ),
        );
      },
      placeholder: (BuildContext context, String str) {
        return Center(child: Utils.loadingWidget);
      },
    );
  }

  Widget _buildCate () {
    var buildBox = (String uri) {
      if (uri == null) {
        return Container(
          margin: EdgeInsets.all(4),
          decoration: BoxDecoration(
            color: Colors.white,
            borderRadius: BorderRadius.circular(3),
          ),
        );
      }
      return InkWell(
        onTap: () {},
        child: Container(
          margin: EdgeInsets.all(4),
          decoration: BoxDecoration(
            borderRadius: BorderRadius.circular(3),
            image: DecorationImage(image: CachedNetworkImageProvider(uri), fit: BoxFit.cover),
          ),
        ),
      );
    };

    return Container(
      margin: EdgeInsets.only(left: 4.px, right: 4.px),
      child: Row(
        children: <Widget>[
          Expanded(flex: 4, child: buildBox(null)),
          Expanded(flex: 6, child: Column(
            children: <Widget>[
              Expanded( child: buildBox(null)),
              Expanded( child: buildBox(null)),
            ],
          ))
        ],
      ),
    );
  }

  Widget _buildNews () {
    return Container(
      height: 42.px,
      alignment: Alignment.center,
      child: Row(
        children: [
          Container(
            margin: EdgeInsets.only(left: 12.px, right: 12.px),
            child: Text("资讯"),
          ),
          VerticalDivider(indent: 12.px, endIndent: 12.px, color: Colors.grey),
          Expanded(child: Container(
            margin: EdgeInsets.only(left: 12.px),
            child: Swiper(
              autoplay: true,
              physics: NeverScrollableScrollPhysics(),
              scrollDirection: Axis.vertical,
              itemBuilder: _buildNewsSlider,
              itemCount: _data.roll.length,
              autoplayDisableOnInteraction: true,
            ),
          ))
        ],
      ),
    );
  }

  Widget _buildNewsSlider(BuildContext context, int index) {
    return Container(
      alignment: Alignment.centerLeft,
      child: Text(_data.roll[index]["info"]),
    );
  }

  Widget _buildProducts () {
    if (_data.info.firstList.length > 0) {
      return SliverList(
        delegate: SliverChildBuilderDelegate((context, index) =>
            ProductItem(_data.info.firstList[index]),
            childCount: _data.info.firstList.length),
      );
    } else {
      return SliverToBoxAdapter(
        child: Container(
          alignment: Alignment.center,
          child: Text("暂时没有数据"),
        ),
      );
    }
  }

  Widget _buildMenu() {
    var widgets = List<Widget>();
    for(var item in _data.menus) {
      widgets.add(Expanded(
          child: GestureDetector(
              onTap: () { Navigator.pushNamed(context, item.url); },
              child: Container(
                alignment: Alignment.center,
                margin: EdgeInsets.all(10.px),
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Expanded(child: Container(
                      width: 40.px,
                      margin: EdgeInsets.only(bottom: 4.px),
                      decoration: BoxDecoration(
                        image: DecorationImage(image: CachedNetworkImageProvider(item.pic), fit: BoxFit.cover),
                        borderRadius: BorderRadius.circular(10.px),
                      ),
                    )),
                    Text(item.name, style: TextStyle(fontSize: 11.px),)
                  ],
                ),
              ))
      ));
    }
    widgets.add(Expanded(
        child: GestureDetector(
            onTap: () { TabsState.inst.doItemTap(3); },
            child: Container(
              alignment: Alignment.center,
              margin: EdgeInsets.all(10.px),
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Expanded(child: Container(
                    width: 40.px,
                    margin: EdgeInsets.only(bottom: 4.px),
                    decoration: BoxDecoration(
                      // image: DecorationImage(image: CachedNetworkImageProvider(""), fit: BoxFit.cover),
                      borderRadius: BorderRadius.circular(10.px),
                    ),
                  )),
                  Text(Cache.isVip ? "会员中心" : "用户中心", style: TextStyle(fontSize: 11.px))
                ],
              ),
            ))
    ));
    return SliverToBoxAdapter(
        child: Container(
          height: 80.px,
          color: Colors.white,
          margin: EdgeInsets.all(6.px),
          child: Row(
            children: widgets,
          ),
        )
    );
  }

  List<Widget> _buildDataList() {
    return <Widget>[
      SliverToBoxAdapter(
          child: Container(
              height: 150.px,
              decoration: BoxDecoration(
                gradient: LinearGradient(
                  begin: Alignment.topCenter,
                  end: Alignment.bottomCenter,
                  colors: [headerColor, DColors.back],
                ),
              ),
              padding: EdgeInsets.only(left: 6.px, right: 6.px),
              child: Swiper(
                scale: 0.9,
                autoplay: true,
                duration: 600,
                autoplayDelay: 5600,
                itemBuilder: _buildSlider,
                itemCount: _data.banner.length,
                onIndexChanged: _onSwipeChange,
                pagination: SwiperPagination(),
                autoplayDisableOnInteraction: true,
              )
          )
      ),
      _buildMenu(),
      SliverToBoxAdapter(
        child: Container(
            height: 150.px,
            child: _buildCate()
        ),
      ),
      SliverToBoxAdapter(
        child: Container(
            height: 46.px,
            color: Colors.white,
            margin: EdgeInsets.all(6.px),
            child: _buildNews()
        ),
      ),
      SliverBar(),
      _buildProducts()
    ];
  }

  _buildNoData() {
    return <Widget>[
      SliverToBoxAdapter(
          child: Container(
              height: 300.px,
              child: Center(child: Utils.loadingWidget)
          ))
    ];
  }

  _buildBody() {
    return EasyRefresh.custom(
        onRefresh: _onRefresh,
        onLoad: _onLoad,
        bottomBouncing: true,
        scrollController: _controller,
        footer: BallPulseFooter(color: DColors.Main),
        header: BallPulseHeader(backgroundColor: headerColor, color: Colors.white),
        slivers: _data == null ? _buildNoData() : _buildDataList(),
    );
  }

  Future _onLoad() async {
    _currentPage ++;
    Log.i("home list load more... page: $_currentPage}");
    // return await Network.inst.getIndex().then((data){
    //   if(!mounted) return;
    //   // _data = data;
    //   // setState(() {
    //   //   _data.info.firstList.addAll(data.info.firstList.toList());
    //   // });
    // }).catchError((err) {});
  }

  Future _onRefresh() async {
    Log.i("refresh home");
    // return await Network.inst.getIndex().then((data){
    //   // if(!mounted) return;
    //   // setState(() {
    //   //   _data = data;
    //   // });
    // }).catchError((err) {});
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: DColors.back,
      appBar: SearchBar(null, color: headerColor, elevation: 0, actions: [
        Consumer<MessageModel>(
          builder: (context, message, child) {
            return FSuper(
              width: 38.px,
              height: double.infinity,
              onClick: () =>
                  Navigator.pushNamed(context, RouteNames.message),
              child1: Icon(IconFonts.message, color: Colors.white),
              child1Alignment: Alignment.centerLeft,
              redPoint: message.data.length > 0,
              redPointText: message.data.length.toString(),
              redPointOffset: Offset(-6.px, 0),
              redPointColor: Colors.white,
              redPointTextStyle: TextStyle(color: Colors.red,
                  fontSize: 10.px, fontWeight: FontWeight.bold),
            );
          },
        )
      ]),
      body: _buildBody(),
      floatingActionButton: _checkColor ? null : InkWell(
        onTap: () => _controller.animateTo(0, curve: Curves.ease,
            duration: Duration(milliseconds: 600)),
        child: Container(
          width: 32.px,
          height: 32.px,
          child: Icon(
              Icons.keyboard_arrow_up_sharp, color: Colors.white),
          decoration: BoxDecoration(
              color: Color.fromARGB(128, 243, 0, 0),
              borderRadius: BorderRadius.circular(10.px)
          ),
        ),
      ),
    );
  }

  void _onScroll() {
    if (_checkColor && _controller.offset > 300) {
        _checkColor = false;
    }

    if (!_checkColor && _controller.offset < 300) {
        _checkColor = true;
    }
  }
}