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Hiding multiple select menus in a form

I have a form that contains 5 select menus. Each menu has different ID / contents etc, but they all have an intial default option value of None. For example...
<select id="Menu_One" name="Menu_One">
<option value="None">None</option>
<option value="SomeValue">A value</option>
</select>
<select id="Menu_Two" name="Menu_Two">
<option value="None">None</option>
<option value="SomeValue">A value</option>
</select>
...and so on.
Once a user has completed the form, I'd like to feature a button that, when clicked, hides any select menu that has been left at the default value of "None".
Have racked my brain to work this one out, but am obviously missing something simple. Ideally needs to be a Javascript / jQuery solution.
Any ideas?

You can do this with plain Javascript. Just add this function call to your button click event.
let hideSelects = function()
{
const elements = document.querySelector("select");
for (var x=0, select; select = elements[x]; x++)
{
if (select.value === 'None')
{
select.style.display = 'none';
}
}
}

Create new drop downs on change event using jQuery

I have drop down menu with some random values. When I select the value onchange event triggers and I want to add new drop down under it, but the new one should have all values except selected one in first drop down. Now when I change value of second one, I need third one that has only non selected values from previous two drop downs and so on until there is no more option to select.
What I have for now is mechanism for adding new drop downs, but it is not working correctly. If I for example select first value it will do the job, new drop down is shown and it has all options except selected one. But then if I go back and try to change option for first drop down third drop down is created. This should not be a case, if drop down already created another drop down it should not do it again. Is it even possible to avoid triggering of new onchange event for drop down that already triggered one? Or maybe some other kind of event is more suitable for this case?
This is my function that does described job:
createNewDropDonws : function() {
var selectWrapper = $('#select-boxes');
$(document).on('change', '.dynamic-select', function() {
var element = $(this);
var optionsLength = (element.find('option').length) - 1;
if(optionsLength === 1) {
return true;
}
var newSelect = $(this).clone();
newSelect.find("option[value='" + element.val() + "']").remove();
newSelect.appendTo(selectWrapper)
});
}
This is my HTML for drop down:
<div id="select-boxes">
<select class="dynamic-select" id="ddlTest">
<option value=""></option>
<option value="Belbin">Belbin</option>
<option value="Raven">Raven</option>
<option value="PPA">PPA</option>
<option value="PPA+">PPA+</option>
<option value="Basic Knowledge">Basic Knowledge</option>
<option value="PCT">PCT</option>
</select>
</div>
And this is simple CSS class:
.dynamic-select{
display: block;
margin: 10px;
}
Does anybody has any idea how this can be implemented correctly by using jQuery?

We can do it in following way:
We are just adding some class like executed once it add another dropdown. And in event handler we are checking if current dropdwon has that class or not. If it is already there then it means we are already done with that dropdown as follows:
$(document).ready(function() {
var selectWrapper = $('#select-boxes');
$(document).on('change', '.dynamic-select', function() {
var element = $(this);
if(element.hasClass("executed"))
return;
var optionsLength = (element.find('option').length) - 1;
if (optionsLength === 1) {
return true;
}
var newSelect = $(this).clone();
newSelect.find("option[value='" + element.val() + "']").remove();
newSelect.appendTo(selectWrapper)
$(this).addClass("executed");
});
});
.dynamic-select {
display: block;
margin: 10px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<div id="select-boxes">
<select class="dynamic-select" id="ddlTest">
<option value=""></option>
<option value="Belbin">Belbin</option>
<option value="Raven">Raven</option>
<option value="PPA">PPA</option>
<option value="PPA+">PPA+</option>
<option value="Basic Knowledge">Basic Knowledge</option>
<option value="PCT">PCT</option>
</select>
</div>

Click on a select html element

I've got a Problem. I have a Select Option in HTML
<div id="eilig">
<select id="eiligselect" data-role="slider">
<option value="2" selected="selected">n. Eilig</option>
<option value="1">Eilig</option>
</select>
</div>
On page default "n. Eilig" is selected. After I have made a ajax post request (with "Eilig" selected) the select option should go back to default ("n. Eilig")
I have tried it with $('#eiligselect').val(2); but this only change the value back but the select option shows "Eilig" (but internal value is "n. Eilig".
This select is with a data-role "slider" which emulates a on / off switch like in ios.
So I think I have to click that slider with javascript to change it back instead of just change the value.
Do you have a clue? Thanks.

Try this : put selected attribute for option with value="2"
$('#eiligselect option[value="2"]').attr('selected',true);

Bind the event on change for slider on select value change,
$('#eiligselect').on('change', function() {
var activeLabel = $('span.ui-slider-label');
var mySlider = $(this);
var new2 = 'n. Eilig';
var new1 = 'Eilig';
if(mySlider.val() == 1) {
activeLabel.text(new2);
} else {
activeLabel.text(new1);
}
mySlider.slider( 'refresh' ); // .trigger( 'create' )
});

This Code may help you solving your problem,
var eiligselect = $("#eiligselect")[0];
eiligselect.seletedIndex = 0;

javascript hide/show items in dropdown list

I started studying javascripting and was wondering if anyone know how to hide values in dropdown list for html?
For example: a dropdwon list with values
Select One
Item1
Item2
Item3
Item4
Item5
I wanna hide the Item 4 and 5, like this and show it when "Show... " is clicked.
Select One
Item1
Item2
Item3
Show 2 more items (Item 4 and 5 hidden)
Is that possible? Below is a piece of code i already started.
var css = select;
var markers = cluster.getMarkers();
var markersLength = markers.length;
var nextOption = new Option("Select One");
css.add(nextOption, 0);
for(var i = 0; i < markersLength; i++) {
nextOption = new Option(markers[i].title);
try {
css.add(nextOption, -1);
} catch (e) {
css.add(nextOption, null);
}
}

You want a generic solution, so tag the more option and the hidden items with classes.
It turns out you cannot consistently style-out options in a select across browsers, so you need to dynamically alter the list options: Refer to this question: How to hide a <option> in a <select> menu with CSS?
Final solution (append elements from another hidden select):
JSFiddle: http://jsfiddle.net/TrueBlueAussie/93D3h/12/
HTML:
Select One
<select class="hidden">
<option>Item4</option>
<option>Item5</option>
<option>Item6</option>
<option>Item7</option>
<select>
<select>
<option>Item1</option>
<option>Item2</option>
<option>Item3</option>
<option class="more">More</option>
</select>
jQuery:
$('select').change(function(){
var $select = $(this);
if ($select.val() == "More"){
$('.more').remove();
$select.append($('.hidden').children());
}
});
Previous info:
Then on then select change event you hide the more option and show the hidden elements:
JSFiddle: http://jsfiddle.net/TrueBlueAussie/93D3h/2/
$('select').change(function(){
var $select = $(this);
if ($select.val() == "More"){
$('.more').hide().prevAll('.hidden').show();
}
});
There appears to be a weird bug in selects as the last item is always visible (even when styled out!). I added a blank entry to fix this for now. This is also why I did not place the hidden items after the more as the last one always shows (what a strange bug - have asked that as a new question: Why is last select option always shown, even when styled out).
You will also want to clear the selected value of "More" as that will no longer exist.
e.g. http://jsfiddle.net/TrueBlueAussie/93D3h/3/
$('select').change(function () {
var $select = $(this);
if ($select.val() == "More") {
$('.more').hide().prevAll('.hidden').show();
$select.val('');
}
});
Followup:
Based on my related question, I was pointed to this one: How to hide a <option> in a <select> menu with CSS? Apparently you cannot style out select options consistently, so adding the items to the list dynamically would be the ideal solution.

Here's my solution:
Html
<select id="test">
<option value="1">Select One</option>
<option value="2">Item 1</option>
<option value="3">Item 2</option>
<option value="4">Item 3</option>
<option value="5">Select Two</option>
<option value="6">Item 4</option>
<option value="7">Item 5</option>
</select>
Script
var array1 = ["1","6","7"];
var array2 = ["1","2","3","4"];
var arrayAll = ["1","2","3","4","5","6","7"];
function hideOptions(array) {
for (var i = 0; i < array.length; i++) {
$('#test option[value="' + array[i] + '"]').hide();
}
}
function showOptions(array) {
for (var i = 0; i < array.length; i++) {
$('#test option[value="' + array[i] + '"]').show();
}
}
$("#test").change(function(){
if($("#test").val()=="5"){
hideOptions(array2);
showOptions(array1);
}
if($("#test").val()=="1"){
hideOptions(array1);
showOptions(array2);
}
});
hideOptions(array1);
here's the fiddle

What about something like:
<head>
<script type="text/javascript">
function makeDynamicOption(target, threshold, messageMore, messageLess) {
var allOptions = collectOptions();
target.addEventListener("change", updateOptions, false); // Use your own event manager
showOptions(threshold);
addMessage(messageMore);
// ---
function collectOptions() {
var options = [];
for(var ii=0; ii<target.options.length; ii++) {
options.push(target.options[ii]);
}
return options;
}
function updateOptions() {
var selectedText = this.options[this.selectedIndex].text;
if (selectedText == messageMore) {
showOptions(allOptions.length);
addMessage(messageLess);
} else if (selectedText == messageLess) {
showOptions(threshold);
addMessage(messageMore);
}
}
function showOptions(upToIndex) {
removeOptions();
for (var ii=0; ii<upToIndex; ii++) {
target.options[ii] = allOptions[ii];
}
}
function removeOptions() {
while(target.options.length > 0) {
target.removeChild(target.options[0]);
}
}
function addMessage(message) {
target.options[target.options.length] = new Option(message, "");
}
}
</script>
</head>
<body>
<select id="foo">
<option value="value1">item1</option>
<option value="value2">item2</option>
<option value="value3">item3</option>
<option value="value4">item4</option>
<option value="value5">item5</option>
</select>
<script type="text/javascript">
makeDynamicOption(
document.getElementById("foo"),
3,
"More...",
"Less..."
);
</script>
</body>
This design separates the lib part (to be linked in the HEAD as an external script) from the activation part. It also lets you inject localized text while generating the view, and preserve existing options in case you have other scripts interacting with them. Note that you should still use your own event manager, and not addEventListener directly as shown in the script, for better cross-browser support.
EDIT: here's how the scripts works:
You call the makeDynamicOptions() function on the select object you want to augment, passing the number of options you want to display, as well as messages to expand/collapse other options. The messages can be written by the view manager, i.e. it could be easily localized if needed.
The first initialization step sees that all original options be collected, so that they can be added back when the user wants to expand the select. Note that we collect the objects themselves, and not only their value/text property values, as other scripts could reference these objects.
The second initialization step registers a change handler on the select, so as to trigger the update on the options list. The script uses addEventListener, but one should substitute one's own event management mechanism, for better cross-browser support.
The last initialization step collapses the select in the intended start position.
The rest is pretty straightforward. Once the user selects an option, the script decides whether the list of options should be repopulated, by analyzing the text of the selected option, and comparing it to the provided expand/collapse labels. If options are to be redrawn, then the script removes all options, adds the expected ones, then adds the new expand/collapse message.
HTH.

Hiding <option>s in IE

I wrote this nifty function to filter select boxes when their value is changed...
$.fn.cascade = function() {
var opts = this.children('option');
var rel = this.attr('rel');
$('[name='+rel+']').change(function() {
var val = $(this).val();
var disp = opts.filter('[rel='+val+']');
opts.filter(':visible').hide();
disp.show();
if(!disp.filter(':selected').length) {
disp.filter(':first').attr('selected','selected');
}
}).trigger('change');
return this;
}
It looks at the rel property, and if the element indicated by rel changes, then it filters the list to only show the options that have that value... for example, it works on HTML that looks like this:
<select id="id-pickup_address-country" name="pickup_address-country">
<option selected="selected" value="CA">Canada
</option>
<option value="US">United States
</option>
</select>
<select id="id-pickup_address-province" rel="pickup_address-country" name="pickup_address-province">
<option rel="CA" value="AB">Alberta
</option>
<option selected="selected" rel="CA" value="BC">British Columbia
</option>
<option rel="CA" value="MB">Manitoba
</option>...
</select>
However, I just discovered it doesn't work properly in IE (of course!) which doesn't seem to allow you to hide options. How can I work around this?
Here's what I've got now:
(function($) {
$.fn.cascade = function() {
var filteredSelect = $(this);
var filteredOpts = this.children('option');
var triggerSelect = $('[name='+this.attr('rel')+']');
triggerSelect.change(function() {
var triggerValue = $(this).val();
filteredOpts.detach()
.filter('[rel='+triggerValue+']').appendTo(filteredSelect)
.filter(':first').attr('selected','selected');
}).trigger('change');
return this;
}
})(jQuery);
Which does work in IE, but still has two problems. The .filter(':first').attr('selected','selected'); bit doesn't seem to do anything in IE (it should select the first visible element). Since I've been using appendTo it currently defaults to the last. And the other problem is that since I detach all the elements immediately, you can't have default values in your HTML.

Options cannot be marked hidden. You must use the SelectElement.add(option) and SelectElement.remove(index)...
Here is a link to remove and add select Options in the same order.
How can I restore the order of an (incomplete) select list to its original order?
Here is a link where I made a post for just doing the most simple thing
How to hide optgroup/option elements?
Note in my post the try catch. This is necessary when adding elements expecially when making the site usable in firefox and IE.