Disable BuddyPress Activity Posting

function vap_disable_activity_posting() {
add_filter( 'bp_get_template_part', 'vap_disable_activity_posting_filter', 10, 3 );

}
add_action('bp_init', 'vap_disable_activity_posting');

function vap_disable_activity_posting_filter( $templates, $slug, $name ) {

if( 'activity/post-form' != $slug )
            return $templates;
}