Develop Reference

Detect focus loss for input element, not onBlur

I'm implementing an autocomplete/combobox in dart. I'm using two elements for this, a <input type="text"> and a <ul> for the suggestions. I want to hide via css style display: none whenever the user leaves the input box. This works when using onBluron the input element.
If the user tries to click an item in the <ul>, the input looses focus and the <ul>is hidden before the click event on the <li> is run.
_listElement = new UListElement();
_textElement = new TextInputElement()
..onBlur((e) => setDisplayToNone(_listElement)); // hide element
I noticed that a jQueryUI implementation does not have this issue and I can not figure out how they detect when to hide the suggestion box. see https://jqueryui.com/autocomplete/
What alternate way can i use to hide the <ul> without hiding it on _textElement.onBlur?
If it helps, the two elements are always wrapped by a <div>. I'm looking for a dart-only solution, although vanilla-js answers that I can rebuild in dart are also appreciated.

Please look at events sequence:
input.focus
li.mousedown
input.blur
li.mouseup
li.click
So you might setup a flag variable, turn it up on li.mousedown, check it on input.blur and decide if you need to hide the list, and then turn it down on li.click

jQuery: generate Select element

I have a table with data, and when I click on a cell in a certain column, I want it to change into a select dropdown for the user to choose a category for that row (which will be written to the database by AJAX but that'll come later).
I've done something similar before with text boxes using this, which works great, but I'm not sure if I'm modifying it correctly.
I've created a JSFiddle which shows the problem I'm having. I click on the text and it turns into a select element as expected, but when I click on that to choose an option, the dropdown doesn't stay open and I can't select anything. Debugging has shown me that when I click the dropdown, it runs the $("td.ChooseType").click() routine again so I've tried to suppress that by removing the class then adding it back on on selection, but that hasn't solved it. On the rare occasion that the dropdown stays open, I am unable to select anything by either mouse or keyboard.
All of the users will be on IE8 unfortunately, so I need it to be compatible with that.
Thanks!

You need to use event delegation, as otherwise that click event is always bound to that td - regardless of whether its class changes.
Simply change:
$("td.ChooseType").click(function() {
To:
$("table").on('click', '.ChooseType', function () {
JSFiddle demo.

Purely as an alternative to the accepted answer, you can remove an attached handler with unbind. So instead of adding and removing the class, you could unbind and rebind your handler. Only requirement is that the function can't be in-line, but has to be declared separately.
example: http://jsbin.com/qiqunici/1/edit
var handler = function () {
$(this).unbind('click', handler); //unbind the clicked element only
//create and change the element
//inside the select-change event, instead of addClass, re-attach:
{
//$(this).parent().addClass("ChooseType").text(selected).find('select').remove();
$(this).parent().click(handler).text(selected).find('select').remove();
}
};
$("td.ChooseType").click(handler);

How to prevent deselection of selected text on blur (focus lost) in html

I have been doing research on this simple sounding issue for a couple of days and I have not seen any result.
In a nutshell my problem is as follows: I would like to select text in a some input field, move focus to another field (or generally speaking some other element), but not lose my selected text.
Such a situation could correspond to a use-case in which I select text in a field, right-click and display a custom popup menu, but do not wish to lose focus of selected text, because I want to do some operations on the previously selected text.
A small code test sample would be (for my initial simple scenario - here I am forcing text selection when the second input field gains focus):
<html>
<head>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<input type="text" id="text1" size="20" value="Test1"/>
<input type="text" id="text2" size="20" value="Test2"/>
<script>
$('#text2').focus( function (evt) {
var target = $('#text1')[0];
target.select();
console.log('active/focused element: ' + document.activeElement.id);
});
</script>
</body>
</html>
I have been searching SO and web for a solution to this and have not seen much if any help.
I am not sure this is even really possible (due to the link between blur and selection lost and focus and selection). I have seen a style property called preventDeselect, in another SO answer - this does not work and I have not even such documentation or browser support for this.
I am quite struggling with this and would appreciate some help: even saying I can't do this at all or maybe some ways to go.
UPDATE:
Just for the record, my user scenario, which refers to text selection and context menu, is a common one (it slipped my mind to mention): just select some text in this page (or in an input type field) and right click to get the browser's default context menu - my scenario is different in that i want to use a custom menu, but with similar behavior to the browser's context menu - which normally allows to select some text, cut/copy the selection, navigate within the context menu without losing the selected text. So I think it should be possible somehow :) to do all these things with a context menu and still have your selection.

Attempting to answer this part of your question:
Such a situation could correspond to a use-case in which I select text
in a field, right-click and display a custom popup menu, but do not
wish to lose focus of selected text, because I want to do some
operations on the previously selected text.
For this use-case, I created a quick fiddle: http://jsfiddle.net/4XE9a/1/
Note: Am using the same getSelection function from #David's answer.
If you select any text and then right-click on the input, a custom popup menu appears. Click "option 1". You will find that the selection is not lost even though the focus has shifted to that anchor tag.
However, for the second part of your question regarding focus shifting to another textbox, #David's answer suffices.
Update: (after your comments)
Please see this updated fiddle: http://jsfiddle.net/783mA/1/
Now, when you select some text and right-click on the input it will show the custom popup menu with three options. Use tab to navigate and press space or click on the highlighted option. (Due to paucity of time I could not implement up/down arrow keys, but the concept remains the same)
This demonstrates your question in the comment that the selection is still not lost while navigating the menu.
Note: You are wanting to visually keep the selection highlight and not lose the selection while clicking anywhere else. Please note that this is not possible because text selection behavior is OS implemented. Browser, html etc do not play a role here. The text selection is lost as soon as you click anywhere outside the context of selection. This is because the system starts expecting a new selection as soon as you click anywhere outside. However, controls without text surface are exempt. Button, scrollbar arrows etc will not cause selection to lose.
To view this behaviour, in the fiddle, select some text and then click any dropdown on the left pane. The text selection is not lost, even visually for that matter.
This is why in the new fiddle above, I purposely used buttons to demonstrate.

You can save each selection in an interval, then retrieve it when you like. Here is an example that pulls the selection when the input has focus and clears the interval on blur:
function getSelection(elm) {
var start = elm.selectionStart;
var end = elm.selectionEnd;
return elm.value.substring(start, end);
}
$('input').focus(function() {
var self = this;
$(this).data('interval', setInterval(function() {
$(self).data('selection', getSelection(self));
},20));
}).blur(function() {
clearInterval($(this).data('interval'));
});
Now you can stuff like:
$('#text2').focus(function() {
console.log('selection in #text1 was: '+$('#text1').data('selection'));
});
Demo: http://jsfiddle.net/qCCY5/

SELECT onChange event

How can I keep track of changes in SELECT element BEFORE user chooses an item using mouse or by pressing Enter?
One can listen to keyUp event, which allows to track user navigating through the list using keyboard. But is there more generic approach, which allows tracking list "prefinal" changes?

I always use focus click listener for this.
$('select').bind('focus click',function(){
//IMACHANGINGMYOPTION!!!!!!!!!!
//var val=$(this).val();
});
The above should be triggered before the on change event:
$('select').change(function(){
//The option has been changed.
});
Explanation: whenever a user focuses select, we do get the value of the selected item, and we can manipulate it before the onchange event if triggered. The click listener is added in case our select is already focused, and the user clicks it to expand before he actually selects an option and triggers a change.
This is an example of usage, that lets us track the previous value:
http://jsfiddle.net/SUKqS/8/

Javascript supports an 'onbeforechange' event which will probably do the trick, but I don't know how widely implemented this is across browsers? If that is supported widely enough, store the previous value before it is changed. Failing that, just store the original values in hidden fields or JS variables.

there is no event that fires when moving the mouse over the select-items.
you can, as you said, track the mouse movement. But as different browsers render the lists differently, that would be a difficult task.
you can however create a selectbox yourself without using the native select

you have to create a function like this example:-
function example(){
jQuery('select#service_billing_state').change(function () {
//your code here
});
}
and you have to call this function in onchange, onblur, onkey , onfocus...

disableSelection on everything except input[type=text]

I am looking to use jQuery's "disableSelection()" function because I have a lot of drag and drop on the pages but I do not want to disable selection on input boxes, just everything else.
I have tried
$('body').disableSelection(); $('input').enableSelection();
$('body').not('input').disableSelection();
still DISABLES EVERYTHING ON THE PAGE. Thank you.

With
$('body').not('input').disableSelection();
You disable selection on every instance of body that is not an input. Since body is not an input this will just disable selection on body.
Try this:
$('body *').not(':has(input)').not('input').disableSelection();
However, like other people pointed out it's probably pretty useless disabling selection on things that aren't draggable in the first place. So maybe you should replace body with .drag or however you can select all the objects that are draggable (keeping the rest of the function the same).

I dont think so disableSelection will work for input textboxes. It's useful for making text elements, or elements that contain text, not text-selectable. For example, if you have a draggable element, you may not want text selection to occur when the user goes to drag the element.