How to pass predefined message and link parameters in facebook feed dialog using android

I want to post a predefind message with link on facebook wall without user intervention .I mean user just log into facebook and my predefind message should be post with link on user's facebook wall.

Below is my code.

public class PostOnFacebookWall {    public static void postOnWall(Facebook facebook , final Context context, final String placeName) {        Bundle params = new Bundle();        params.putString("message", placeName);        facebook.dialog(context, "feed", params ,new DialogListener() {            public void onFacebookError(FacebookError e) {            }            public void onError(DialogError e) {            }            public void onComplete(Bundle values) {                Toast.makeText(context, placeName+" for today's hangout has been posted on your facebook wall. ", Toast.LENGTH_LONG).show();            }            public void onCancel() {            }        });    }}

I've looked so many links about my question like below

http://stackoverflow.com/questions/11316683/adding-content-to-facebook-feed-dialog-with-new-facebook-sdk-for-android

which passed all the parameter like "link","description","image" and much more.Someone is saying that u have to pass all the parameters.I just want to predefind messages and link over that.

My message is should be "Let's hangout at " and here placeName should be a link.And this complete msg i want to pass from my code .I don't want that my code opens dialog where user enters it's message.