How to create a page showing only articles in a certain language?
Use the Internationalizations Views module, which extends the i18n module with multilingual support for views.

Also, to make view results correspond to the language switcher, add a filter for Content Translation: User's Current Language, which is the language that an authenticated user has set in the user settings (it is NOT the same as the current browser language or the site language).

Note: The Internationalizations Views module only has an alfa version for D7, but right now there are over 41K users using this version. Therefor I think "DEV" is not a valid release qualifier for that version anymore, because +41K users can't be wrong, right?

PS: I'm assuming this question is about D7.