What I tried to accompanlish is to clear the line chart when there is no selection made in the slicer. I have put the following measure into the visual level filters, and set the "show items when the value: contains Y", and it is working fine with single selection, but when I tried to select mutltipe selection in the slicer which is allowed in my case, the filter is not working (it does not filter anything, and left the line chart blank). The measure code (see below) is from the forum in the past and I borrowed to use it in my project.
Please anybody is able to modify the following measure to make it work with multiple selections in the slicer to do the filter, and clear the line chart when there is no selection is made by selecting the clear icon on the top right of the slicer.
CheckSlicerSelected = if(calculate(distinctcount([MyFieldName]), allselected(MyTableName[MyFieldName]))=1,"Y","N")
You may be able to wrap your IF statement in another IF statement that checks if ISBLANK(SELECTEDVALUE([SlicerMeasure])). Otherwise, in order to assist, please see this post regarding How to Get Your Question Answered Quickly: https://community.powerbi.com/t5/Community-Blog/How-to-Get-Your-Question-Answered-Quickly/ba-p/38490
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