flutter - 如何在 Flutter 的 ListView 中添加复选框？

Question

我从 How to create a checkbox using listview 中获取了以下代码当检查一项时，它会检查所有项目。我如何修复代码以不检查所有项目？

class CheckBoxInListView extends StatefulWidget {
  @override
  _CheckBoxInListViewState createState() => _CheckBoxInListViewState();
}

class _CheckBoxInListViewState extends State<CheckBoxInListView> {
  bool _isChecked = false;

  List<String> _texts = [
    "InduceSmile.com",
    "Flutter.io",
    "google.com",
    "youtube.com",
    "yahoo.com",
    "gmail.com"
  ];

  @override
  Widget build(BuildContext context) {
    return ListView(
      padding: EdgeInsets.all(8.0),
      children: _texts
          .map((text) => CheckboxListTile(
                title: Text(text),
                value: _isChecked,
                onChanged: (val) {
                  setState(() {
                    _isChecked = val;
                  });
                },
              ))
          .toList(),
    );
  }
}

Answer 1

只需制作一个“_isChecked”变量列表并使用它。

class CheckBoxInListView extends StatefulWidget {
  @override
  _CheckBoxInListViewState createState() => _CheckBoxInListViewState();
}

class _CheckBoxInListViewState extends State<CheckBoxInListView> {
  List<String> _texts = [
    "InduceSmile.com",
    "Flutter.io",
    "google.com",
    "youtube.com",
    "yahoo.com",
    "gmail.com"
  ];

  List<bool> _isChecked;

  @override
  void initState() {
    super.initState();
    _isChecked = List<bool>.filled(_texts.length, false);
  }

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
      itemCount: _texts.length,
      itemBuilder: (context, index) {
        return CheckboxListTile(
          title: Text(_texts[index]),
          value: _isChecked[index],
          onChanged: (val) {
            setState(
              () {
                _isChecked[index] = val;
              },
            );
          },
        );
      },
    );
  }
}