Question

我是新手，这是我的问题，选择图标后，我将选择容器中的所有其他项目

选择后，我无法将容器的颜色更改为绿色不仅在图标上，而且在按下容器功能时

class _AddEmpToProjectState extends State<AddEmpToProject> {
  bool _isSelected = false;
  Container addEmpListTile() {
    return Container(
        margin: EdgeInsets.fromLTRB(10.0, 0.0, 10.0, 10.0),
        padding: EdgeInsets.all(5.0),
        decoration: BoxDecoration(
            borderRadius: BorderRadius.circular(10.0), color: Colors.white),
        child: Container(
          child: ListTile(
              leading: CircleAvatar(
                backgroundImage: AssetImage('assets/tom.jpg'),
              ),
              title: Text('Sam'),
              subtitle: Text('Site Manager'),
              trailing: InkWell(
                  onTap: () {
                    _isSelected = !_isSelected;
                    setState(() {});
                  },
                  child: _isSelected
                      ? Icon(
                          Icons.done,
                          color: Colors.green,
                          size: 35.0,
                        )
                      : Icon(
                          Icons.add,
                          color: Colors.deepPurple,
                          size: 35.0,
                        ))),
        ));
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.deepPurple,
      appBar: AppBar(
        title: Text('Add Employees'),
        elevation: 0.0,
        actions: <Widget>[
          IconButton(
            icon: Icon(
              Icons.search,
              color: Colors.white,
            ),
            onPressed: () {},
          ),
          IconButton(
            icon: Icon(
              Icons.done,
              color: Colors.white,
            ),
            onPressed: () {},
          )
        ],
      ),

      body: ListView.builder(
        itemCount: 10,
        itemBuilder: (BuildContext context, int index) {
          return addEmpListTile();
        },
      ),

    );
  }
}

在轻按容器时，将颜色更改为绿色，并应移至顶部如果取消选择必须返回到数组小部件索引这是我应该做的

Answer 1

不仅需要选择一个项目（布尔值），还需要以某种方式跟踪选择了哪个项目（某种标识符）。

一种解决方案是使用index作为跟踪号码

class _AddEmpToProjectState extends State<AddEmpToProject> {
  -bool _isSelected = false;
  +Set<int> _selected = Set();

...
class _AddEmpToProjectState extends State<AddEmpToProject> {
 Set<int> _selected = Set();

 Container addEmpListTile(int index) {

    ...
    onTap: () {
     setState(() {
       if(_selected.contains(index)) {
        _selected.remove(index);
       } else {
         _selected.remove(index);
       };
     }
    },
    child: _selected.contains(index)
       ? Icon(Icons.done)
       : Icon(Icons.add)
  }

...

  build() {
    ...
    itemBuilder: (BuildContext context, int index) {
        return addEmpListTile(index);  // <-- add index here
    ...
  }

容器图标在选择一项时全部更改

1 个答案: