[Solved]-eclipse e4 - How to let a preference value from the ConfigurationScope be injected after value change?-eclipse

i run into the same problem and this is how i resolved it:

@inject
public void trackinterface(@preference(nodepath = "/configuration/"
            + activator.plugin_id, value = "interfacepref") string interfacename)     {
        if (interfacename == null || interfacename.isempty()) {
        // use default preference
        ieclipsepreferences preferences = defaultscope.instance
                .getnode(activator.plugin_id);
        interfacename = preferences.get("interfacepref", "multicast");
        }
        else
        lblinterfacename = interfacename;