Text transformation on field (Remove spaces)

I'm trying to remove all spaces from a field after the user has entered text (on a specific form only). Currently I tried to use the modified method on the form's datasource, but as expected I received a stack trace error due to an endless loop. Has anybody come across automatic transforms for fields or any other way to accomplish this?

Current code

publicvoid modified()

{

    this.setValue(strReplace(this.getValue()," ", ""));

    super();

}