How can I set a value with Jquery ?

Hello , my friend , wonderful script . Congratulation .
I have a question , I am trying to change the value with the jquery , like this -

$(document).on('click', '.edit-item', function(event){
$("#myselect").val(1);
}

or
$(document).on('click', '.edit-item', function(event){
$('#myselect>option:eq(3)').prop('selected', true);
}

but is not changing , maybe has some script that has to tell the jquery to refresh , after on click .
Do you know what do I have to do to make it works ?
Thanks

Start by reproducing the provided jQuery change handlers against the jquery-nice-select plugin and inspect how the custom dropdown reflects the underlying select value. Done means setting #myselect programmatically causes the visible custom control to display the selected option.

Written by the indexing model from the issue text.