How to pass a string that is contained in a Observable

Hi I’m trying to pass a string by router from an Observable by clicked event

function ApriListaCompleta(args){
    var Canale =; //id_canale is the string contained in the Observable
    router.push("ListaCompletaVideo", Canale);

But when I try to get the string from it return a blank Observable.
What I have to do?

You can not pass Observables as router arguments. Router arguments must be serialisable data types.

You can pass a simple string, an object, an array, or a combination of those. Just don’t try to pass complex objects that have functions on them (which Observables do).