hey.dart

import 'dart:math' as math;
import 'package:flutter/material.dart';
import 'package:grata/components/molecules/service-card.dart';
import 'package:grata/helpers/forListview.dart';
import 'package:grata/providers/data.dart';
import 'package:grata/providers/instit.dart';
import 'package:grata/screens/components/molecules/single-app-bar.dart';
import 'package:grata/screens/components/molecules/positioned-card.dart';
import 'package:grata/screens/components/pages/timeandOrder.dart';
import 'package:grata/screens/models/single-instit-model.dart';
import 'package:provider/provider.dart';

class SingleInstitutionArg {
  final String institutionId;
  SingleInstitutionArg({@required this.institutionId});
}

class SingleInstitution extends StatefulWidget {
  static const String routeName = "singleProduct"; 

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

class _SingleInstitutionState extends State<SingleInstitution> with SingleTickerProviderStateMixin{
  double deviceWidth = 0;
  double _opacityMainCard = 1;
  final ScrollController _controller = ScrollController();
  double offsetDis = 120;
  Institution institution;
  DataProvider dataProvider;
  final ValueNotifier<double> cardOpacity = ValueNotifier<double>(1);

  Future<void> _upadteOpacityCard() {
    if (_controller.offset < offsetDis) {
      double newV = math.pow((_controller.offset - offsetDis) / offsetDis, 2);
      newV = math.pow(newV, 4);
      cardOpacity.value = newV;
    } else {
      if (cardOpacity.value != 0) {
        // setState(() {
        //   _opacityMainCard = 0;
        // });
        cardOpacity.value = 0;
      }
    }
    return null;
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    final SingleInstitutionArg args = ModalRoute.of(context).settings.arguments;
    final value = Provider.of<DataProvider>(context);
    final actualValue = value.institutions
        .firstWhere((value) => value.id == args.institutionId);

    if (dataProvider != value) {
      dataProvider = value;
      value.getServiceByInstitutionId(args.institutionId);
      this.institution = actualValue;
    }
  }

  @override
  void initState() {
    super.initState();
    _controller..addListener(_upadteOpacityCard);
  }

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

  @override
  Widget build(BuildContext context) {
    return SingleInstitutionAncestor(
      child: Scaffold(
        backgroundColor: Color.fromRGBO(244, 244, 244, 1),
        floatingActionButton: FloatingActionButton(
          elevation: 1,
          backgroundColor: Colors.orange,
          onPressed: () {
            Navigator.of(context).push(MaterialPageRoute(
                builder: (BuildContext context) => OrderWidget()));
          },
          child: Icon(Icons.check),
        ),
        bottomSheet: Container(
          decoration: BoxDecoration(
            color: Colors.transparent,
            borderRadius: BorderRadius.only(
              topLeft: Radius.circular(16),
              topRight: Radius.circular(16),
            ),
          ),
          padding:
              const EdgeInsets.only(left: 36, right: 36, top: 8, bottom: 8),
          child: FittedBox(
            // fit: BoxFit.cover,
            child: Text(
              "ORDER 3 FOR KZT 500000",
              style: TextStyle(color: Colors.orange),
            ),
          ),
          height: 60,
        ),
        body: Stack(
          children: <Widget>[
            ScrollConfiguration(
              behavior: MyBehavior(),
              child: CustomScrollView(
                controller: _controller,
                slivers: <Widget>[
                  SingleAppBar(imagePath: institution.imageBackgroundUrl),
                  SliverList(
                    delegate: SliverChildListDelegate([
                      SizedBox(
                        height: 100,
                      ),
                      Column(
                        children: dataProvider.currentServices.map<Widget>(
                          (value) {
                            return ServiceCard(value);
                          },
                        ).toList(),
                      ),
                      Column(
                        children: dataProvider.currentServices.map<Widget>(
                          (value) {
                            return ServiceCard(value);
                          },
                        ).toList(),
                      ),
                      SizedBox(height: 600),
                    ]),
                  )
                ],
              ),
            ),
            PositionedCard(cardOpacity.value, institution.name),
          ],
        ),
      ),
    );
  }
}
// assets/logo_hey.jpg