run Qt example demo'ToDoList'+add ExclusiveGroup component failedfail

Juliana

hey guys,I'm a freshman and recently ran the example code 'ToDoList' from Qt6 to learn.I wanted to add a radio module for tags in NewTaskForm.ui.qml,so I add the 'RadioButton QML Type' sample code from Official website to that file.But the Qt creator shows that the ExclusiveGroup component is unknown:Unknown component:M300.
I checked the imported info in this qml file:

import QtQuick
import QtQuick.Controls
import QtQuick.Layouts
import ToDoList
import CustomControls

It doesn't point the version,but I think it's not a problem,since the example code also not point,but originally it can run corrently.

I also make no change to other configuration in this example code 'ToDoList'.

So who can help me solve my confusion?
Thanks!