How to use events in GWT Frame - events

Question

I would like to capture all events within a GWT frame. I've found several ways to do this, but they only return mousemove and mouseout events. I also need keypresses, input, etc. The goal is to capture the events and send them to another client by using websockets, and then replicate them on the other side (co-browsing).
I am using a page on the same domain within the frame.
public class ESinkFrame extends Frame implements EventListener {
public ESinkFrame(String src){
super(src);
DOM.sinkEvents(getElement(), Event.KEYEVENTS);
DOM.sinkEvents(getElement(), Event.MOUSEEVENTS);
}
public void onBrowserEvent(Event event) {
System.out.println( "sunk event: " + DOM.eventGetTypeString(event) );
}
}
And when I use it, I also try to attach a different way of grabbing the events.
ESinkFrame frame = new ESinkFrame("http://127.0.0.1:8888/other.html");
RootPanel.get().add(frame);
FrameElement frameElt = frame.getElement().cast();
Document frameDoc = frameElt.getContentDocument();
BodyElement body = frameDoc.getBody();
Element el = body.cast();
DOM.setEventListener(el, new EventListener()
{
public void onBrowserEvent(Event event)
{
Window.alert("test");
}
});
DOM.sinkEvents(el, Event.KEYEVENTS);
Event.addNativePreviewHandler(new NativePreviewHandler(){
public void onPreviewNativeEvent(NativePreviewEvent event) {
String eventName = event.getNativeEvent().getType();
if (event.isFirstHandler() /* && (event.getTypeInt() & Event.MOUSEEVENTS) == 0*/)
System.out.println("PreviewHandler: " + eventName);
}
});