Question

IndexedStack解决了底部导航索引更改时保留内容的问题。但是，当子状态改变时，我怎么找不到重建IndexedStack的方法。儿童状态更改仅在重新启动应用程序时反映出来。

更改IndexedStack时

_children不更新。

下面是代码：

 Widget myBody() {
    Widget myBodyWidgetData = SizedBox.shrink();
    if (_isSelectedConnectionReady &&
        _selectedConnectionId is int &&
        _selectedConnectionId >= 0 &&
        _selectedConnection.runtimeType == Connection) {
      myBodyWidgetData = IndexedStack(
        index: _selectedBottomNavigationIndex,
        children: _children,
      );
    } else if (_isSelectedConnectionReady && _selectedConnectionId < 0) {
      final GlobalKey<RefreshIndicatorState> _refreshIndicatorKey =
          new GlobalKey<RefreshIndicatorState>();
      myBodyWidgetData = RefreshIndicator(
        key: _refreshIndicatorKey,
        onRefresh: setSelectedConnection,
        child: SingleChildScrollView(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              Padding(
                padding: const EdgeInsets.fromLTRB(10, 20, 10, 20),
                child: Text(
                  "Kindly add a connection to manage woocommerce",
                  textAlign: TextAlign.center,
                ),
              ),
              Container(
                height: 45,
                width: 200,
                child: RaisedButton(
                  color: Theme.of(context).primaryColor,
                  textColor: Colors.white,
                  onPressed: () {
                    Navigator.push(
                      context,
                      MaterialPageRoute(
                        builder: (context) => AddConnectionPage(
                          refreshConnectionsList: setSelectedConnection,
                        ),
                      ),
                    );
                  },
                  child: Text(
                    "Add Connection",
                    style: Theme.of(context).textTheme.button,
                  ),
                ),
              )
            ],
          ),
        ),
      );
    } else {
      myBodyWidgetData = Center(
        child: SpinKitPulse(
          color: Theme.of(context).primaryColor,
          size: 70,
        ),
      );
    }
    return myBodyWidgetData;
  }

完整代码：

import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:woocommerceadmin/src/common/widgets/MyDrawer.dart';
import 'package:woocommerceadmin/src/connections/widgets/AddConnectionPage.dart';
import 'package:woocommerceadmin/src/customers/widgets/CustomersListPage.dart';
import 'package:woocommerceadmin/src/db/ConnectionDBProvider.dart';
import 'package:woocommerceadmin/src/db/models/Connection.dart';
import 'package:woocommerceadmin/src/orders/widgets/OrdersListPage.dart';
import 'package:woocommerceadmin/src/products/widgets/ProductsListPage.dart';
import 'package:woocommerceadmin/src/reports/widgets/ReportsPage.dart';
import 'package:woocommerceadmin/src/config.dart';
import 'package:flutter_spinkit/flutter_spinkit.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Woocommerce Admin',
      theme: ThemeData(
        primarySwatch: Colors.purple,
        textTheme: TextTheme(
            headline: TextStyle(
              fontSize: 24.0,
              fontWeight: FontWeight.bold,
              // backgroundColor: Colors.purple,
              // color: Colors.white
            ),
            subhead: TextStyle(
              fontSize: 18.0,
              fontWeight: FontWeight.bold,
            ),
            body1: TextStyle(
              fontSize: 14.0,
            ),
            button: TextStyle(
              color: Colors.white,
              fontWeight: FontWeight.bold,
              fontSize: 16,
            )),
      ),
      home: HomePage(),
    );
  }
}

class HomePage extends StatefulWidget {
  HomePage();

  final _HomePageState _homePageState = _HomePageState();

  @override
  _HomePageState createState() => _homePageState;

  Future<void> setSelectedConnection() async {
    await _homePageState.setSelectedConnection();
  }
}

class _HomePageState extends State<HomePage> {
  int _selectedConnectionId = -1;
  bool _isSelectedConnectionReady = false;
  Connection _selectedConnection;

  int _selectedBottomNavigationIndex = 0;
  List<Widget> _children = [];

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

  @override
  void setState(fn) {
    if (mounted) {
      super.setState(fn);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: myAppBar(),
      drawer: MyDrawer(),
      body: myBody(),
      bottomNavigationBar: myBottomNavigation(),
    );
  }

  Future<void> setSelectedConnection() async {
    SharedPreferences prefs = await SharedPreferences.getInstance();

    int selectedConnectionId;
    try {
      selectedConnectionId = prefs.getInt("selectedConnectionId");
    } catch (e) {
      selectedConnectionId = -1;
      _isSelectedConnectionReady = true;
    }

    List<Connection> connectionList =
        await ConnectionDBProvider.db.getAllConnections();

    if (selectedConnectionId is int &&
        selectedConnectionId >= 0 &&
        connectionList.isNotEmpty) {
      if (connectionList[selectedConnectionId] is Connection) {
        setState(() {
          _selectedConnectionId = selectedConnectionId;
          _selectedConnection = connectionList[_selectedConnectionId];
          _isSelectedConnectionReady = true;
          _children = [
            ReportsPage(
              baseurl: _selectedConnection.baseurl,
              username: _selectedConnection.username,
              password: _selectedConnection.password,
            ),
            OrdersListPage(
              baseurl: _selectedConnection.baseurl,
              username: _selectedConnection.username,
              password: _selectedConnection.password,
            ),
            ProductsListPage(
              baseurl: _selectedConnection.baseurl,
              username: _selectedConnection.username,
              password: _selectedConnection.password,
            ),
            CustomersListPage(
              baseurl: _selectedConnection.baseurl,
              username: _selectedConnection.username,
              password: _selectedConnection.password,
            )
          ];
        });
      }
    }
  }

  Widget myAppBar() {
    Widget myAppBarWidgetData;
    if (!_isSelectedConnectionReady &&
        _selectedConnectionId is int &&
        _selectedConnection is! Connection) {
      myAppBarWidgetData = AppBar(
        title: Text("Setup"),
      );
    }
    return myAppBarWidgetData;
  }

  Widget myBody() {
    Widget myBodyWidgetData = SizedBox.shrink();
    if (_isSelectedConnectionReady &&
        _selectedConnectionId is int &&
        _selectedConnectionId >= 0 &&
        _selectedConnection.runtimeType == Connection) {
      myBodyWidgetData = IndexedStack(
        index: _selectedBottomNavigationIndex,
        children: _children,
      );
    } else if (_isSelectedConnectionReady && _selectedConnectionId < 0) {
      final GlobalKey<RefreshIndicatorState> _refreshIndicatorKey =
          new GlobalKey<RefreshIndicatorState>();
      myBodyWidgetData = RefreshIndicator(
        key: _refreshIndicatorKey,
        onRefresh: setSelectedConnection,
        child: SingleChildScrollView(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              Padding(
                padding: const EdgeInsets.fromLTRB(10, 20, 10, 20),
                child: Text(
                  "Kindly add a connection to manage woocommerce",
                  textAlign: TextAlign.center,
                ),
              ),
              Container(
                height: 45,
                width: 200,
                child: RaisedButton(
                  color: Theme.of(context).primaryColor,
                  textColor: Colors.white,
                  onPressed: () {
                    Navigator.push(
                      context,
                      MaterialPageRoute(
                        builder: (context) => AddConnectionPage(
                          refreshConnectionsList: setSelectedConnection,
                        ),
                      ),
                    );
                  },
                  child: Text(
                    "Add Connection",
                    style: Theme.of(context).textTheme.button,
                  ),
                ),
              )
            ],
          ),
        ),
      );
    } else {
      myBodyWidgetData = Center(
        child: SpinKitPulse(
          color: Theme.of(context).primaryColor,
          size: 70,
        ),
      );
    }
    return myBodyWidgetData;
  }

  Widget myBottomNavigation() {
    Widget myBottomNavigationWidgetData = SizedBox.shrink();
    if (_isSelectedConnectionReady &&
        _selectedBottomNavigationIndex >= 0 &&
        _selectedConnection.runtimeType == Connection) {
      myBottomNavigationWidgetData = BottomNavigationBar(
          // backgroundColor: Colors.purple, //Not Working Don't Know why
          showSelectedLabels: true,
          showUnselectedLabels: true,
          unselectedItemColor: Config.colors["lightTheme"]
              ["bottomNavInactiveColor"],
          selectedItemColor: Config.colors["lightTheme"]["mainThemeColor"],
          currentIndex: _selectedBottomNavigationIndex,
          onTap: (int index) {
            setState(() {
              _selectedBottomNavigationIndex = index;
            });
          },
          items: const <BottomNavigationBarItem>[
            BottomNavigationBarItem(
              icon: Icon(Icons.insert_chart),
              title: Text('Reports'),
            ),
            BottomNavigationBarItem(
              icon: Icon(Icons.assignment),
              title: Text('Orders'),
            ),
            BottomNavigationBarItem(
              icon: Icon(Icons.collections),
              title: Text('Products'),
            ),
            BottomNavigationBarItem(
              icon: Icon(Icons.people),
              title: Text('Customers'),
            ),
          ]);
    }
    return myBottomNavigationWidgetData;
  }
}

Answer 1

我遇到了相同的问题，已通过将GlobalKey（）分配给孩子并将其分配给孩子。

示例：

setState(() {
    _children.removeAt(0);
    _children.insert(0, CustomWidget(customData: customData, key: GlobalKey()));
});

当其子级特定状态更改时如何重建IndexedStack

1 个答案: