Kendo Ui Dropdownlist Set Visible via Javascript

Try like this,

$("#ddl").closest(".k-widget").hide();
 $("#ddl").closest(".k-widget").show();

One should always use the API docs to see the features of a widget. In this case, there is no API method for hiding a widget, but you can hide its wrapper element:

var dropdownlist = $("#ddl").data("kendoDropDownList");
dropdownlist.wrapper.hide(); // call wrapper.show() to make it visible again