Are you using GWT-RPC? I'm not sure I understand your problem completely. So if I have a service like:
public interface MyService extends RemoteService { public Entity fetchEntity(String id); } public interface MyServiceAsync { void fetchEntity(String id, AsyncCallback<Entity> callback); } then, in the GWT code, something triggers the service. Typically it is via a button click or some event. You seem to indicate that you are doing it by passing the id as a URL parameter, like: http://host/my.gwt.application/Application.html?id=123 You should be able to parse the URL using the Window.Location.getPath() to get the url param with a regex. Once you have that, you do this: MyServiceAsync service = GWT.create(MyService.class); service.fetchEntity(id, new AsyncCallback<Void>() { onFailure(Throwable t) { Window.alert("service call failed: "+t.getMessage()); } onSuccess(Entity e) { // do something with the entity } }); After onSuccess( ) -- you populate the form with whatever. On Mon, Nov 16, 2009 at 5:02 PM, David C. Hicks <dhi...@i-hicks.org> wrote: > I'm sure I must be making this harder than it needs to be, but I'm > having zero success doing it. > > Entering a new form, I'd like to display the name of an entity that was > selected on the the calling page. The calling page is a Struts2 JSP, so > I don't have the entire entity. I only have the entity's ID, passed in > as a parameter on the request URL. That's easy enough to get, and I > even have a service set up to go get the full entity once I have the > ID. The problem is that the service is asyncronous. So, I get a Null > Pointer Exception at the point where I try to set the data I'm > retrieving into a label because the call hasn't yet completed. > > I'd rather not pass the name on the request URL - trying to avoid the > messy encoding/decoding problems. I've tried to create an AsyncCallback > class that included a hook that I could "wait" for, but this only seemed > to create an infinite wait loop. > > So, now I'm wondering if I need to somehow "bind" the retrieved data to > a field on my form so that it will populate when the call completes. > Then again, maybe this is overkill, too. > > Is there a better way to solve this problem? > Thanks, > Dave > > -- > > You received this message because you are subscribed to the Google Groups > "Google Web Toolkit" group. > To post to this group, send email to google-web-tool...@googlegroups.com. > To unsubscribe from this group, send email to > google-web-toolkit+unsubscr...@googlegroups.com<google-web-toolkit%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/google-web-toolkit?hl=. > > > -- Zeno Consulting, Inc. home: http://www.zenoconsulting.biz blog: http://zenoconsulting.wikidot.com p: 248.894.4922 f: 313.884.2977 -- You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To post to this group, send email to google-web-tool...@googlegroups.com. To unsubscribe from this group, send email to google-web-toolkit+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-web-toolkit?hl=.