Are you using my Menu Manager to create the menus? If so you will need to keep a reference as a global variable to each created checked item and use that to check / uncheck it.
No, i am using the standard methods from the Designer.
B4X:
If mi.Text = "MenuItem1" Then
If Pane5status = True Then
Pane5.Visible = False
Pane5status = False
Else
Pane5.Visible = True
Pane5status = True
End Sub
The MenuItem1 is a checkable one...
Is your menu manager possible to handle that ?