Please refer to this link , is a multiple select box to select sub-activity base on what is picked in main-activity, its working pretty well now.
Based on change request, I want to make the action to show only the optgroup in sub-activity when it being select, means when you select main-activity option 1 and 2
, sub-activity
are show optgroup for 1 and 2
, the rest are hide and not visible, please advise, thanks.
you need to get not selected options and hide()
them in subactivity. and not forget to show selected ones.
//get not selected ones
var arr1 = $('#filterActivity option:not(:selected)');
//iterate and hide
$("#filterSubActivity").children("optgroup[label='" + arr1[j].value + "']").hide();
here is demo: http://jsfiddle.net/btevfik/q62PK/