I try to get a login screen where the language can be changed. There is no problem to do that after I have logged in. But how can I change it immediately after I switched the language? (For example the Horde Email Platform has this possibility. But unfortunately it is written in PHP. Here is an example.)
I tried it already with a valueChangeListener. But how can I update the page itself? Is this possible in JSF?
If the welcome page is a login page and you're using container-based authentication, it might require a little more creativeness, but same general idea.
Also, it's a good idea to keep a cookie so that the user doesn't have to select every time.
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