如何在颤动中为BottomNavigationBar菜单提供onPress功能？

Question

我在 flutter 中有一个底部导航栏，我想要的是点击底部栏的各个小部件，它应该将我导航到下一页

    Widget _bottemTab() {
    return new BottomNavigationBar(


    currentIndex: _currentIndex,
    onTap:(newIndex) => setState((){_currentIndex = newIndex;}),
    type: BottomNavigationBarType.fixed,
    items: [
      new BottomNavigationBarItem(
          icon: Image.asset(
            "assets/home.png",
            width: 24.0,
            height: 24.0,
          ),
          title: Text(
            'Home',
          ),
      ),
      new BottomNavigationBarItem(
          icon: Image.asset(
            "assets/shopping-bagg.png",
            width: 24.0,
            height: 24.0,
          ),
          title: Text(
            'Mall',
          )),
      new BottomNavigationBarItem(
          icon: Image.asset(
            "assets/qr-code.png",
            width: 24.0,
            height: 24.0,
          ),
          title: Text(
            'Scan',
          )),
      new BottomNavigationBarItem(

          icon: Image.asset(
            "assets/bank.png",
            width: 24.0,
            height: 24.0,
          ),
          title: Text(
            'Bank',
          )),



      new BottomNavigationBarItem(
          icon: Image.asset(
            "assets/delivery.png",
            width: 24.0,
            height: 24.0,
          ),
          title: Text(
            'Inbox',
          )),


    ]);
      }

我想要的是点击底部栏的各个小部件，它应该将我导航到我为底部导航视图的每个菜单项分别创建的下一页..任何帮助表示赞赏

Answer 1

在您的build()方法中，您可以添加此逻辑。

@override
Widget build(BuildContext context) {
  Widget widget = Container(); // default
  switch (_currentIndex) {
    case 0:
      widget = FirstPage();
      break;

    case 1:
      widget = SecondPage();
      break;

    case 2:
      widget = ThirdPage();
      break;
  }

  return Scaffold(
    body: widget,
    // ...
  );
}

更新：

我不确定你是怎么做到的，在这里你可以看到一个正确的小例子。

int _index = 0;

@override
Widget build(BuildContext context) {
  Widget child = Container();

  switch(_index) {
    case 0:
      child = FlutterLogo(colors: Colors.orange);
      break;

    case 1:
      child = FlutterLogo();
      break;
  }

  return Scaffold(
    appBar: AppBar(),
    bottomNavigationBar: _bottomTab(),
    body: SizedBox.expand(child: child),
  );
}

Widget _bottomTab() {
  return BottomNavigationBar(
    currentIndex: _index,
    onTap: (int index) => setState(() => _index = index),
    backgroundColor: Colors.deepPurple,
    items: [
      BottomNavigationBarItem(icon: Icon(Icons.looks_one), title: Text("1")),
      BottomNavigationBarItem(icon: Icon(Icons.looks_two), title: Text("2")),
    ],
  );
}