Same question!

        require_once(dirname(dirname(dirname(__FILE__))) . '/engine/start.php');
        gatekeeper();
        $content = get_input('content','');
        $content = explode(',',$content);
        $type = $content[0];
        $subtype = $content[1];
        $orient = get_input('display');
        $callback = get_input('callback');
        if ($type == 'all') {
            $type = '';
            $subtype = '';
        }
        $body = '';
        if (empty($callback)) {
            //set a view for the wire to extend
            $area1 = elgg_view("activity/thewire");
            //set a view to display newest members
            $area1 .= elgg_view("riverdashboard/newestmembers");   
            //set a view to display a welcome message
            $body .= elgg_view("riverdashboard/welcome");
            //set a view to display a site wide message
            $body .= elgg_view("riverdashboard/sitemessage");
        }
        switch($orient) {
            case 'mine':
                            $subject_guid = $_SESSION['user']->guid;
                            $relationship_type = '';
                            break;
            case 'friends':    $subject_guid = $_SESSION['user']->guid;
                            $relationship_type = 'friend';
                            break;
            default:        $subject_guid = 0;
                            $relationship_type = '';
                            break;
        }
        $river = elgg_view_river_items($subject_guid, 0, $relationship_type, $type, $subtype, '') . "</div>";
        // Replacing callback calls in the nav with something meaningless
        $river = str_replace('callback=true','replaced=88,334',$river);
        $nav = elgg_view('riverdashboard/nav',array(
                                                            'type' => $type,
                                                            'subtype' => $subtype,
                                                            'orient' => $orient
                                                        ));

. . . etc other code leading to page_draw()

;-)

Dhrup，thanks! I'll try.

@Dhrup

I can't work out with this code snippet because of my poor programming capabilities. My goal is displaying the latest wire post for users not logged in. Could you give me more hints? Thanks!

@ Blue

Have you thought about using the custom index with widgets?  It provides this an many more possibilities without using any coding at all. :-)

It was recently updated you can check it out here