FEATURE REQUEST: Badge Support

[ChaseFlorell]

Is your feature request related to a problem? Please describe.

Describe the solution you'd like
I'd love the ability to add a BadgeView to each calendar item. Effectively I'd like to add icons or numbers to specific dates in order to glean more information at a glance. The badge view should be bound to an interface IBadgeView { DateTimeOffset Date{ get; } } where the required value is the date and the concretion can have arbitrary data that is bound to the SelectorTemplate of the BadgeView

Describe alternatives you've considered

Additional context (Optional)

Use Case 1:
Creating multiple entries in a database for a given date, It would be nice to be able to put the "Entry Count" as a numeric value on the calendar for that date.

Use Case 2:
An entry for a given date has a state (let's use "yes" and "no" for this example). It would be nice to be able to display a ✔️ or an ❌ on the calendar for that date.

[ME-MarvinE]

For the BadgeView, would it not be possible to inherit from CalendarDay (or implement the ICalendarDay interface) to add your extra properties and then use the DayTemplate property of the CalendarView to consume them? More info about customising a day can be found on the Displaying Dates wiki page.

Although I think you would have to create the BadgeView manually if you don't want to use Syncfusion's BadgeView or Telerik's BadgeView. I know there was a BadgeView in the Xamarin Community Toolkit but this doesn't seem to be ported to MAUI yet. I found this discussion about doing so.

It seems like this could be nice example in the sample app.

[ME-MarvinE]

Did you manage to do what you wanted to do?