setVariableValue based on crosstab selection

Hi,

Since the newly supported cascading filters for UNX don't seem to support multiple selection, I'm using crosstabs as an alternative. I'd then like to use the (multiple) selection I make in the crosstab as input for a setVariableValue command of a second datasource.

I'd thought to use this script:

var memberarray = CROSSTAB.getSelectedMembers("_CaDxYKPsEeWyjqW5S58ucQ");

var string = '';

memberarray.forEach(function(element, index) {

     string = string + element.internalKey +'/';

});

DS_3.setVariableValue("variable", string.split('/'));

This script, however, gives an 'cannot convert from stringarray to VariableValue' error. Does anyone have an idea how I can use a crosstab selection as input for a setVariableValue command?