flutter - BottomNavigationBar 标题未显示在 Flutter 中

Question

为什么底部导航栏标题不显示？它应该显示在图标下方

class FlutterProject extends StatefulWidget {
  final String title = "Flutter Bottom Tab demo";

  @override
  GoalsListState createState() {
    return GoalsListState();
  }
}

class GoalsListState extends State<FlutterProject>
    with SingleTickerProviderStateMixin {
  int _cIndex = 0;

  void _incrementTab(index) {
    setState(() {
      _cIndex = index;
    });
  }

  final List<Widget> _children = [
    new One(),
    new Two(),
    new Three(),
    new Four(),
    new More()
  ];

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        body: _children[_cIndex],
        bottomNavigationBar: BottomNavigationBar(
          currentIndex: _cIndex,
          type: BottomNavigationBarType.shifting,
          items: [
            BottomNavigationBarItem(
                icon:
                    Icon(Icons.graphic_eq, color: Color.fromARGB(255, 0, 0, 0)),
                title: new Text('One')),
            BottomNavigationBarItem(
                icon: Icon(Icons.report_problem,
                    color: Color.fromARGB(255, 0, 0, 0)),
                title: new Text('Two')),
            BottomNavigationBarItem(
                icon: Icon(Icons.work, color: Color.fromARGB(255, 0, 0, 0)),
                title: new Text('Three')),
            BottomNavigationBarItem(
                icon: Icon(Icons.domain, color: Color.fromARGB(255, 0, 0, 0)),
                title: new Text('Four')),
            BottomNavigationBarItem(
                icon: Icon(Icons.menu, color: Color.fromARGB(255, 0, 0, 0)),
                title: new Text('Five')),
          ],
          onTap: (index) {
            _incrementTab(index);
          },
        ));
  }
}

我在这里错过了什么？

Answer 1

当提供超过 3 个 BottomNavigationBar 项目时，如果未指定类型，则根据 https://docs.flutter.io/flutter/material/BottomNavigationBar/BottomNavigationBar.html 更改为 BottomNavigationBarType.shifting .这条信息应该在类(class)的文档中突出显示。很容易忽略它的位置(我忽略了它)。

添加类型:BottomNavigationBarType.fixed on BottomNavigationBar

BottomNavigationBar(
   type: BottomNavigationBarType.fixed,
   items: <BottomNavigationBarItem>[],
)