java.lang.IllegalArgumentException:

Vaadin 6 / 7 / 8
1

I have this error:

"java.lang.IllegalArgumentException: Trying to navigate to an unknown state 'user' and an error view provider not present"

I want to navigate to ‘user’ throught editing the url and I always failed doing that. So is there any way to delete that error? or redirect me to the main page instead? how can I catch that error?

btw: I am using navigator in all of my pages.

2

Hello Lance,

Have you registered varioiu views wiht navigator in UI?

Some thing like this has to be done in your UI class
Navigator navigator = new Navigator(this,subLayout); ui.setNavigator(navigator); navigator.addView("", new [b] DefaultView [/b]());// register your default view navigator.addView("user", new [b] UserView [/b]());// register your user view

3

Yes, I did… but when I try to edit it on my url address at my web browser I got an error.

4

Hi Lance,

It should certainly work just by typing the “user” url manually. Could you attach a simple test UI that exhibits the problem you’re having?

About catching the “not found” error, the exception message gives a hint: you have to set an error view using Navigator.setErrorView(), or if you want more flexibility, a dedicated ViewProvider via Navigator.setErrorViewProvider().

5

Wow… this really works… Thank you Johannes…

I have another question… I want that my url to be “project/#user” NOT “project/#!user”. It’s not a big deal but it’s a little annoying everytime I saw ‘!’… :slight_smile:

I have here now are my my addView(“user”, new User())… and it returns ‘#!’.
I am planning to use setUriFragment(“user”) because it returns # only. How can use it? How can I call the class User?

6

Yes, it is possible. The reason we use the so-called “hashbang” URIs is that they enable the site to be
crawlable by Google
 - although not unless the application also has some special support for crawlable views.

Anyway, you’ll want to write a custom UriFragmentManager and pass it as the Navigator’s NavigationStateManager:

public class BanglessFragmentManager extends Navigator.UriFragmentManager {
        @Override
        public String getState() {
            return getFragment() != null ? getFragment() : "";
        }

        @Override
        public void setState(String state) {
            setFragment(state);
        }
}
7

Wow this is really amazing…It did work with just a flick of my hand… :3 :smiley: Thank you very much…

here you said that using ViewProvider is much flexible… actually I use the setErrorView() because this is much easier than ViewProvider. I research online about ViewProvider but got no sample program. When do I need to use ViewProvider?

Thank you Johannes for immediate reply… You’re a big help… :slight_smile: