flutter - 只更改一个项目样式而不是每个人。改变了所有 ListTile 而不是一个

Question

当我点击 ListTile 后，应该只更改一项，但是当我点击那里时更改了所有 ListTile。

  class _HomeScreenState extends State<HomeScreen> {
  bool checked = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ListView.builder(
        itemCount: 7,
        itemBuilder: (BuildContext context, int i) {
          child: return Container(
            decoration: new BoxDecoration(
              color: checked ? Colors.teal : Colors.white
            ),
            child: ListTile(
              onTap: () => setState(() => checked = true),
              title: Text("My product"),
            ),
          );
        },
      ),
    );
  }
}

Answer 1

试试下面的代码，

class _HomeScreenState extends State<HomeScreen> {
  int checkedIndex = -1;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ListView.builder(
        itemCount: 7,
        itemBuilder: (BuildContext context, int i) {
          return Container(
            decoration: BoxDecoration(
                color: checkedIndex == i ? Colors.teal : Colors.white
            ),
            child: ListTile(
              onTap: () => setState(() => checkedIndex = i),
              title: Text("My product"),
            ),
          );
        },
      ),
    );
  }
}