Post on facebook wall without any dialogs from an android app?

I would like to post on the facebook wall from android app.But I don't want any dialog boxes to come up.

(1)The user login prompts should also be prevented.I will be storing the username and password in shared Preferences.Is there some way to pass the user id and password so that authentication happens without the dialogs.

(2)It should just post the content on wall and return a response message so that i can display on the screen as "Post Successful".

Can you let me know what all things that i have mentioned above are possible and how it can be done.I would be good if someone can provide links which explains the concepts and It would be even better if someone could post a bit of code.

P.S:I have alrea开发者_运维问答dy gone through How to post on facebook wall using Facebook android SDK, without opening dialog box but it doesn't mention anything of user login prompt and frankly haven't quiet grasped the entire thing.