I make use of the Show column if setting of a dimension.
In my case I defined a variable vShowFieldPlantCostCentre with an initial value as '0' (hidden).
Then we use the Variable Input bundled extension, where the user selects from a dropdown box whether to show the column or not. The variable input dropdown box toggles the $(vShowFieldPlantCostCentre) variable between '0' and '1'.
The Show column if expression is:
=$(vShowFieldPlantCostCentre) = 1
So if the vShowFieldPlantCostCentre variable is equal to '1' then the column will show in the pivot table.
Note that the variables are reset to their default values when the model reloads. So if the model reloads the user will see that his selections (which are linked to variables) revert back to their default values, and in this case causes this column selections to be reset.
I hope, you read the question. However, here is quick overview of problem.
For example: I have Pivot table with SUM Expression. When it execute expression will evaluate and generate the rows for dimension. Now, I have 10 rows 5 consist on Negative (-) and 5 Positive (+) value. I would like to hide and show the Negative (-) rows when select filter "Negative Value".
Expression and Application is already attached with this thread.