Develop Reference

HTML, CSS: Form input list with scrollbar, but not a dropdown, all options visible

I have this code for a dropdown list input in a form:
<form action="/action_page.php" method="get">
<label for="browser">Choose your browser from the list:</label>
<input list="browsers" name="browser" id="browser">
<datalist id="browsers">
<option value="Edge">
<option value="Firefox">
<option value="Chrome">
<option value="Opera">
<option value="Safari">
...
</datalist>
<input type="submit">
</form>
It shows this:
However it only shows the list after I click on the input element.
I'd like the dropdown list to always be shown. Is it possible to achieve?

datalist element is hidden in rendering
According to HTML spec:
In the rendering, the datalist element represents nothing and it, along with its children, should be hidden.
What you describe in the question and screenshot seems to be the expected behavior: i.e. displaying the list of options when input is active. If you need to display the list at all times, perhaps you might want to consider an additional (or an alternative) element to do that.

Backing to a form with a chosen dropdown forgets its value visually

Using the chosen lib I run into the following issue, you can reproduce it yourself by going to their show-and-tell-page:
https://harvesthq.github.io/chosen/
Steps to reproduce:
In their standard select section, select -any country you want- in both the standard dropdown and the chosen dropdown
Click 'fork on github'(or any link) to leave the page
Navigate back by hitting the back button in chrome
The standard dropdown shows you the previously selected country
The chosen dropdown is empty (but under the hood the value is selected, according to what I'm seeing with my form. It just is not showing)
So this leads to confusion. When the user would back and then go forward again by submitting the form(in my case) it would use another value than what is shown.
My form basically looks like:
<form id="myForm" action="${home}mySite/foo/bar" method="GET">
<select id="bar" name="barName" class="chosen-select">
<option value="a">foo 1</option>
<option value="b">foo 2</option>
<option value="c">foo 3</option>
<option value="d">foo 4</option>
</select>
<input type="submit" value="Continue"/>
</form>
If I remove the class="chosen-select" it works as I expect, but I lose chosen's nice search feature which I want. I've tried messing around with
<option value="a" selected="selected">Foo 1</option>
in the dropdown, but that doesn't help.
I've also tried changing the method="GET" to POST but there is no difference in behaviour. It still works as in the example link I provided.
The chosen lib generates the following in on the page:
<div class="chosen-container chosen-container-single" title="" id="parkingZoneOwner_chosen" style="width: 40%;"><a class="chosen-single">
<span>Foo 1</span>
<div><b></b></div>
</a>
<div class="chosen-drop">
<div class="chosen-search">
<input class="chosen-search-input" type="text" autocomplete="off">
</div>
<ul class="chosen-results"></ul>
</div></div>
But nothing about the generated html looks wrong to me, even after backing to the page.
I tried this in the js (events):
<script type="text/javascript">
$(function () {
$(document).ready(function () {
$(".chosen-select").chosen({
width: "40%",
search_contains: true
});
$('.chosen-select').on('chosen:ready', function(evt, params) {
$(".chosen-select").val("a");
});
});
});
$('.chosen-select').on('chosen:ready', function(evt, params) {
// alert("reached")
// I had really high hopes for this one:
$('.chosen-select').trigger('chosen:updated');
//Also tried this one:
$('#myForm')[0].reset();
});
Anyone know a way to fix this? Either the chosen dropdown needs to show what actually will be submitted in the form or the entire form maybe could be reset to default values somehow.

This solved it in the end, turning off autocomplete on the form.
<form id="myForm" action="${home}mySite/foo/bar" autocomplete="off" method="GET">
I don't know why this works.

multiple select drop down gets reset when calling window.print()

I happened to notice that my multiple select dropdowns are getting reset when I call the window.print() function on the click of a button to print the current page.
This seems to have been working on Chrome v80 but it seems the issue is part of v81.
I am using a workaround for this by displaying values in an input box (rather than the multiple select tag) on the print button click. I was wondering if there is a better solution to the issue.
A sample code is given below: Selected option values are retained in Chrome v80 but not on v81 when the print button is clicked.
<html>
<head>
<script>
function printPage(){
window.print();
}
</script>
</head>
<body>
<select id="test" name="test" multiple>
<option value="1">My val 1</option>
<option value="2" selected>My val 2</option>
<option value="3">My val 3</option>
<option value="4" selected>My val 4</option>
<option value="5">My val 5</option>
</select>
<input type="button" value="print" onclick="printPage()"/>
</body>
</html>

Is your issue that the elements do not appear selected in the printout, or that after pressing print, the page forgets what was selected and the user must select them again? If it is just about appearing in the printout, it is possible you have "background graphics" unchecked in the "more options" section of the print dialog

Cannot Fill Textbox with Javascript After Editing

I have a simple drop-down box and I am successfully using Javascript to automatically fill a textbox when a drop-down item is selected.
Once I edit any of the textbox's automatically filled text, or use a "Clear" button to erase textbox, the drop-down list no longer replaces fills the textbox.
How can I continue to use the drop-down box once the user has altered the textbox?
JSFiddle Version
HTML code:
<select id="dropdown" onchange="preset();">
<option value="">Select a person:</option>
<option value="Abe" >Abe</option>
<option value="Bob" >Bob</option>
<option value="Cal" >Cal</option>
<option value="Dan" >Dan</option>
</select>
<input type=Submit value="Clear" onclick="document.getElementById('mytext').value='';">
<textarea id="mytext"></textarea>
Javascript code:
function preset() {
document.getElementById("mytext").innerHTML=document.getElementById("dropdown").value
}

You use innerHTML in one place, and value in another. Using value in both fixes it.
Demo

Update the submit button to this:
<input type=Submit value="Clear" onclick="document.getElementById('mytext').innerHTML='';">

Editable Dropdown?

I have a php page with 4 text boxes, each need a "drop down" when the text boxes have the focus. Clicking the options would populate the (editable) text box(es) and close the drop down. The text boxes are of course part of html forms. How can I do this inline with javascript or ajax using minimal code?

Unless you are calling a webserver ajax is useless here.
You will need to have or create a div, since it is below your input box, and absolute positioning will be useful to ensure it is appropriately placed relative to the input box.
You should only have one function, so it should be adaptable to the input fields, hence the reason for absolute positioning.
You will want to track the keypress and mouseclick events in this div, and ensure that only one is open at a time, so have an onblur so that if the user clicks anywhere else the div closes.

if you use jquery you can do this extremely easily.
you could tweak this to your liking:
<html>
<script language='javascript' src='http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js'></script>
<script language='javascript'>
$(document).ready(function(){
$("input[type='text']").focus(function(){
$(this).parent().find('select').show();
});
$('select').change(function(){
$(this).parent().find('input[type="text"]').val($(this).val());
$(this).hide();
}).blur(function(){
$(this).hide();
});
});
</script>
<form>
<fieldset>
<input type='text' /><br/>
<select style='display:none;'>
<option value=''>----</option>
<option value='1'>opt1</option>
<option value='2'>opt2</option>
<option value='3'>opt3</option>
</select><br/>
</fieldset>
<fieldset>
<input type='text' /><br/>
<select style='display:none;'>
<option value=''>----</option>
<option value='1'>opt1</option>
<option value='2'>opt2</option>
<option value='3'>opt3</option>
</select><br/>
</fieldset>
<fieldset>
<input type='text' /><br/>
<select style='display:none;'>
<option value=''>----</option>
<option value='1'>opt1</option>
<option value='2'>opt2</option>
<option value='3'>opt3</option>
</select><br/>
</fieldset>
<fieldset>
<input type='text' /><br/>
<select style='display:none;'>
<option value=''>----</option>
<option value='1'>opt1</option>
<option value='2'>opt2</option>
<option value='3'>opt3</option>
</select><br/>
</fieldset>
</form>
</html>
if your select options need to be dynamic, ajax is very simple with jquery. if you already know what's going to be in there, have the php populate the hidden select boxes, and the focus event will show them.