flutter - 我可以将TabBar中的标签向左而不是中心对齐吗？

Question

我想做的是将标签向左对齐。我看过this和this，但它们对我没有帮助。我也尝试过包括一列，这样我就可以使用交叉轴匹配，但是这给了我这种类型不匹配的问题“参数类型“列”不能分配给参数类型“PreferredSizeWidget”。我认为必须有一种简单的方法，但是我没有想法

child: Scaffold(
  appBar: AppBar(
    title: Text(advisoryService.number),
    flexibleSpace: Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: <Widget>[],
    ),
    bottom: TabBar(
      labelPadding: EdgeInsets.only(left: 8, right: 8),
      isScrollable: true,
      tabs: <Widget>[
        Tab(
          text: 'General',
        ),
        Tab(
          text: 'Financial',
        ),
        Tab(
          text: 'Experts & Participants',
        ),
      ],
    ),
  ),
  body: TabBarView(

Answer 1

编辑:我已经更新了完整代码并正在演示
您可以使用Alignment.centerLeft
并使用Container控制整个TarBar大小，并将其设置为相对屏幕宽度

    appBar: AppBar(
        title: Text(widget.title),
        bottom: PreferredSize(
          preferredSize: const Size.fromHeight(20.0),
          child: Align(
            alignment: Alignment.centerLeft,
            child: Container(
              width: MediaQuery.of(context).size.width / 2,
              child: TabBar(
                isScrollable: true,
                controller: _tabController,
                tabs: [
                  Tab(text: 'Tab 1'),
                  Tab(text: 'Tab 2'),
                  Tab(text: 'Tab 3'),
                  Tab(text: 'Tab 4'),
                  Tab(text: 'Tab 5'),
                ],
              ),
            ),
          ),
        ),
      ),

工作演示



完整的代码

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final appTitle = 'Tabs Demo';
    return MaterialApp(
      title: appTitle,
      home: MyHomePage(title: appTitle),
    );
  }
}

class MyHomePage extends StatefulWidget {
  final String title;

  const MyHomePage({Key key, this.title}) : super(key: key);

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

class _MyHomePageState extends State<MyHomePage>
    with SingleTickerProviderStateMixin {
  int _tabIndex = 0;

  TabController _tabController;

  @override
  void initState() {
    super.initState();
    _tabController = TabController(vsync: this, length: 5);
  }

  void _toggleTab() {
    _tabIndex = _tabController.index + 1;
    _tabController.animateTo(_tabIndex);
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        home: Scaffold(
      floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
      bottomNavigationBar: BottomAppBar(
        notchMargin: 20,
        child: new Row(
          // mainAxisSize: MainAxisSize.max,
          mainAxisAlignment: MainAxisAlignment.end,
          children: <Widget>[
            InkWell(
              onTap: () {
                _toggleTab();
              },
              child: Text(
                'Next >',
                style: TextStyle(fontSize: 20, color: Colors.red),
              ),
            )
          ],
        ),
      ),
      appBar: AppBar(
        title: Text(widget.title),
        bottom: PreferredSize(
          preferredSize: const Size.fromHeight(20.0),
          child: Align(
            alignment: Alignment.centerLeft,
            child: Container(
              width: MediaQuery.of(context).size.width / 2,
              child: TabBar(
                isScrollable: true,
                controller: _tabController,
                tabs: [
                  Tab(text: 'Tab 1'),
                  Tab(text: 'Tab 2'),
                  Tab(text: 'Tab 3'),
                  Tab(text: 'Tab 4'),
                  Tab(text: 'Tab 5'),
                ],
              ),
            ),
          ),
        ),
      ),
      body: TabBarView(
        controller: _tabController,
        children: [
          Card(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: <Widget>[
                ListTile(
                  leading: Icon(Icons.album),
                  title: Text('Hello 1'),
                  subtitle: Text('Click on Next Button to go to Tab 2.'),
                ),
              ],
            ),
          ),
          Card(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: <Widget>[
                ListTile(
                  leading: Icon(Icons.album),
                  title: Text('Hello 2'),
                  subtitle: Text('Click on Next Button to go to Tab 3'),
                ),
              ],
            ),
          ),
          Card(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: <Widget>[
                ListTile(
                  leading: Icon(Icons.album),
                  title: Text('Hello 3'),
                  subtitle: Text('The End'),
                ),
              ],
            ),
          ),
          Card(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: <Widget>[
                ListTile(
                  leading: Icon(Icons.album),
                  title: Text('Hello 4'),
                  subtitle: Text('The End'),
                ),
              ],
            ),
          ),
          Card(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: <Widget>[
                ListTile(
                  leading: Icon(Icons.album),
                  title: Text('Hello 5'),
                  subtitle: Text('The End'),
                ),
              ],
            ),
          ),
        ],
      ),
    ));
  }
}