Filter context doesnt apply with custom date slicer

[MelvinM]

Hello everyone,

I have implemented a new Date Picker following this quick tutorial in order to extend the possibility of filtering my data. However, I am struggling with calculating measures for the previous period selected in my Date Picker.

First, here is how my model is built:

here is the measure I want to calculate in a modified filter context:

here is a quick example of how my Dateslicer selection is built:

I then put the "Period" column in a slicer in order to select the "Last calendar week" option and then filter the Datedim table in the corresponding manner and to replace the classic between date slicer.

However, since I have implemented this configuration, I am not able to calculate the previous_period_measure with this original formula (startOfPrevPeriod and endOfPrevPeriod being out of the data range filtered with the slicer) :

Previously, without the DateSlicerSelection, the DateDim[FullDateAlternateKey] was in a between date slicer and everything was working fine. Despite the fact that I have absolutely no idea of how to fix it, I have made few observations:

I am able to get the very first Date of my DimDate table even with it is filtered with he following formula : 

Modifying my measure calculation with the following formula, I got the result for the current period selection and not the previous one:

Please, does someone has an idea on how to fix this problem ?

Best Regards,

Melvin