Measure that returns TRUE or FALSE when a field is on a visual

[webportal]

My visual is a table that contains two fields:

Calendar[Date]

[Sum of Sales] - a measure

I'm looking for a simple measure that returns TRUE or FALSE when the field Calendar[Date] is on the visual (thus affecting the context).

So, 

HASONEFILTER(Calendar[Date]) returns FALSE

HASONEVALUE(Calendar[Date]) also returns FALSE

ISFILTERED(Calendar[Date])  also returns FALSE

etc...

I could use:

COUNTROWS('Calendar') < CALCULATE(COUNTROWS(ALL('Calendar')))

But, is there a DAX function for this?

Thank you!

[Greg_Deckler · Accepted solution]

@webportal - Wait, I might have lied. I am known for this. ISINSCOPE

[webportal]

Interesting one, thanks for this!

[Greg_Deckler]

@webportal - No, not exactly, this is how @marcorusso does it:

https://www.sqlbi.com/articles/displaying-filter-context-in-power-bi-tooltips/