Post on Facebook wall using Facebook Android SDK without opening dialog box

i applied following code and could successfully posted my message on wall.

public void postOnWall(String msg) {
        Log.d("Tests", "Testing graph API wall post");
         try {
                String response = mFacebook.request("me");
                Bundle parameters = new Bundle();
                parameters.putString("message", msg);
                parameters.putString("description", "test test test");
                response = mFacebook.request("me/feed", parameters, 
                        "POST");
                Log.d("Tests", "got response: " + response);
                if (response == null || response.equals("") || 
                        response.equals("false")) {
                   Log.v("Error", "Blank response");
                }
         } catch(Exception e) {
             e.printStackTrace();
         }
    }