Javascript Selectbox refresh necessary in YUI 3, when selecting none? - select

Question

I'm using YUI 3 to let someone click "Select All" or "Select None" and then have the selectbox select all the items or unselect all of them, respectively. Here's my code:
// This selects all
Y.on('click',function (e) {
selectBoxNode.get("options").each(function () {
this.removeAttribute('selected');
this.setAttribute('selected','selected');
});
}, selectAllNode
);
// This selects none
Y.on('click',function (e) {
selectBoxNode.get("options").each(function () {
this.setAttribute('selected','false');
this.removeAttribute('selected');
});
selectBoxNode.('selectedIndex',-1);
}, selectNoneNode
);
selectAllLink, selectNoneLink, and selectBoxNode are self-evident, properly returned Nodes. Update: selectAll works, I had to manually remove the 'selected' attribute for each and re-add it.
The selectNoneLink doesn't work: it unselects only the elements that weren't before selected... although DOM inspection shows that the selectedIndex attribute is indeed changed to -1, so maybe it needs a refresh?
Any help would be appreciated. If this happens in all frameworks, that would be nice to know as well.
Thanks!

Answer 1

This worked for me.
YUI().use('node', function(Y) {
Y.get('#unsel').on('click', function(e) {
Y.get('select').get('options').set('selected',false);
});
Y.get('#sel').on('click', function(e) {
Y.get('select').get('options').set('selected', true );
});
});