function selectRow(check,id){
        var tr = $('row_'+id);
        var color = '#ffffff';

        if (check.checked == true){
            color = '#fffdec';
        }

        tr.getChildren().each(function(el){
            el.setStyle('backgroundColor', color);
        });
    }

function confirmAction(){
        if ($('mass_action').value == 'delete'){
            var answer = confirm ("You're about to permanently delete invoices from your system, are you sure you want to do this?");
            if (!answer){
                return false;
            }
        }
        return true;
}

function selectAll(obj){
    var checked = obj.checked;

    $$('input').each(function(el){
        if (el.name == 'invoice_id'){
            el.checked = checked;
            selectRow(el,el.value);
        }
    });
}