flutter - 复选框在对话框中切换

Question

对话框中的复选框切换不实时更新吗？？？？
当我必须onChanged而不更新对话框中的复选框时

var is_checked = false;
    void updateCheckBox() {
      showGeneralDialog(
        pageBuilder: (context, _, __) {
          return new Row(
            children: <Widget>[
              new Checkbox(
                value: is_checked,
                onChanged: (bool value) {
                  this.setState((){
                  is_checked = !is_checked;
                  });
                },
              ),
              Text(
                '  Confirm bets before placing',
                style: TextStyle(
                    fontFamily:"Roboto",fontSize: 14.0, fontWeight: FontWeight.normal),
              )],
          );
        },
      );
    }

Answer 1

更改此:

              new Checkbox(
                value: is_checked,
                onChanged: (bool value) {
                  this.setState((){
                  is_checked = !is_checked;
                  });
                },
              ),

到这个:

              new Checkbox(
                value: is_checked,
                onChanged: (bool value) {
                  this.setState((){
                  is_checked = value;
                  });
                },
              ),

When the checkbox is tapped, if tristate is false (the default) then the onChanged callback will be applied to !value. If tristate is true this callback cycle from false to true to null.

检查文档:

https://api.flutter.dev/flutter/material/Checkbox/onChanged.html