Flutter PopupMenuButton - don't close the menu when selected - flutter

Question

I have a list of checkbox items (PopupMenuItem) inside my popup menu, which is triggered by a popupMenuButton. I want the user to be able to select a number of checkboxes, but as soon as one item is selected it closes the window.
Is there any way to prevent this? I need it to stay open, or alternatively force it open again immediately.
(I tried creating my own PopupItem class to override the "handleTap()", but I need to update the state of the parent menu view, which I can't call from another class. So Ive removed that again.)
class TopicsNotificationMenu extends StatefulWidget {
List<Topic> topics = [];
TopicsNotificationMenu(this.topics);
#override
_TopicsNotificationMenuState createState() =>
_TopicsNotificationMenuState();
}
class _TopicsNotificationMenuState extends State<TopicsNotificationMenu> {
_TopicsNotificationMenuState();
_updateTopics(_tp){
setState(() {
if(_tp.value == true){
_tp.value = false;
}else{
_tp.value = true;
_registerTopic(_tp.name);
}
});
}
#override
Widget build(BuildContext context) {
return PopupMenuButton(
onSelected: (value) {
_updateTopics(value);
},
itemBuilder: (BuildContext context) {
return widget.topics.map((var tp) {
var _icon = (tp.value == true) ? Icons.check_box : Icons.check_box_outline_blank;
return PopupMenuItem(
value: tp,
child: ListTile(
leading: Icon(_icon),
title: Text(tp.name),
),
);
}).toList();
});
}

Answer 1

You can try to reopen it each time after the user's selection. I made an example here
Alternatively, I would advise creating your own widget with the desired behaviour.

Answer 2

I had to create my own widget for this. In summary, I wanted a floating list in the top-right of my screen with a list of checkboxed items. When I press the items they become checked/unchecked but the window remains open until I click off it. I used the following widget tree:
An OverlayEntry widget so that I could place it anywhere floating above the app
-> added the SafeArea widget so that my padding would include the notification bar at the top of the phone
-> a Gesture Detector, so that on tapping off it I could close it
-> a column with CrossAxisAlignment.end so that it was placed in the top-right
-> a container widget with some padding
-> a Material for elevation shading and to contain a list
-> The Listview
-> The List Tiles with icon and Text for each item. The icon was either the ticked or unticked graphic, depending on it's value (which is stored as a boolean in an array)
onTap of a ListTile it updated the state of the widget and dispayed it again. There is no visual blinking, it is instant.
onTap of the Gesture Detector it simply removes the widget.