Bootstrap Multiselect update option list on flow

Answer 1

As an alternative to multiselect('dataprovider', data) you can build the list with jquery append exactly the way you did in your question. The only change you need to make is to delay the rebuild until after the ajax request is complete.

var buildDrivers = $.getJSON('resources/orders/drivers.json', function(data) { 
   $.each(data, function(i, driver) {
      $('#toolbar select[name="drivers"]').append(''+driver+'');
   });
});
buildDrivers.complete(function() {
    $('.multiselect').multiselect('rebuild');
});

see http://api.jquery.com/jquery.getjson/ for documentation