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;
}