BIRT Parameter, filter a multivalue list box parameter from a textbox parameter

Question

I'm trying to create a parameter windows with the first parameter [Text Box] as input for the second parameter [LIst box multivalues]. THe current situation

I try scripting dataset of second parameter with the same script of 2 multivalue list box but it's not working.

// Do that if your selections are in String type.
var stringArray = params["Country"].value.toString().split(",");
var result = "";
for(var i =0 ; i < stringArray.length ; i++){
    if(i==0){
        result = "'"+stringArray[i]+"'";
    }
    else{
        result = result+",'"+stringArray[i]+"'";
    }
}

// For String
this.queryText = this.queryText.replace("'CountryParam'", result);

//For integer (the first part is useless)
//this.queryText = this.queryText.replace("'CountryParam'", params["Country"].value);

I think i should script the second parameter but i don't find anything. How can I do it?