带抖动的导航栏

Question

材料设计准则包括名为Navigation rail的组件。

如何使用颤动创建导航栏？

Answer 1

最新版本的Flutter 1.17包含一个内置的NavigationRail组件。

import 'package:flutter/material.dart';

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

/// This Widget is the main application widget.
class MyApp extends StatelessWidget {
  static const String _title = 'Flutter Code Sample';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: _title,
      home: MyStatefulWidget(),
    );
  }
}

class MyStatefulWidget extends StatefulWidget {
  MyStatefulWidget({Key key}) : super(key: key);

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

class _MyStatefulWidgetState extends State<MyStatefulWidget> {
  int _selectedIndex = 0;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Row(
        children: <Widget>[
          NavigationRail(
            selectedIndex: _selectedIndex,
            onDestinationSelected: (int index) {
              setState(() {
                _selectedIndex = index;
              });
            },
            labelType: NavigationRailLabelType.selected,
            destinations: [
              NavigationRailDestination(
                icon: Icon(Icons.favorite_border),
                selectedIcon: Icon(Icons.favorite),
                label: Text('First'),
              ),
              NavigationRailDestination(
                icon: Icon(Icons.bookmark_border),
                selectedIcon: Icon(Icons.book),
                label: Text('Second'),
              ),
              NavigationRailDestination(
                icon: Icon(Icons.star_border),
                selectedIcon: Icon(Icons.star),
                label: Text('Third'),
              ),
            ],
          ),
          VerticalDivider(thickness: 1, width: 1),
          // This is the main content.
          Expanded(
            child: Center(
              child: Text('selectedIndex: $_selectedIndex'),
            ),
          )
        ],
      ),
    );
  }
}

查找现场演示here。>>

Here是官方文档。