Hi Lenny,
Using only out-of-the-box Mendix you could do this if you group the records per months in the domain. Create a “Month” entity and associate all dated objects to the correct Month object. Now you can achieve something like your drawing using nested list views.
Or maybe the marketplace has a widget that can do something like this. Or you could create your own widget, but that may be a lot of work.
Would one of these options work for you?