I have used two date slicers that are used for parameter binding for direct query. I am not able to display those slicers as calendar even though they are in date format. As soon as i did parameter binding with those slicer it turned to dropdown.
Please make sure you add the date column or date/time column into the slicer instead of the date hierachy.
Here I create a sample with Date and Date/Time type Parameters in Power Query Editor. And turn on "Enable load".
If you turn on "Auto date/time for new file" in Option, Power BI will create a date hierachy in your data model. When you add the date or date/time column into the slicer, Power BI will add the hierachy automaticly. If you add hierachy into slicer, you could dropdown only.
I suggest you to select the column in Field.
And then if your column in date or date/time type, you will be able to use all kind of function as below.
Best Regards, Rico Zhou
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