Event for select-dropdown menu closing - javascript

Is there an javascript event for the closing of an expanded dropdown (select-element)?
The blur event does only fire when the element loses its focus, but that seems to be independently of the dropdown.
The change event does only fire when the client selects an options instead of clicking somewhere else.

Try with "change" event. It will be fired when you select value from list.

Related

Mouseover event not fired on <select> options list item hovers

I don't see any mouseover events from the <select> tag's options list. For example on this page: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/select I can add an event listener document.addEventListener('mouseover', console.log) and I will see all other mouseover events except as soon as I am hovering on the options list.
Any ideas on why a mouseover event isn't fired here? I am aware that I can listen for a change event on successful selection by user, just baffled why the mouseover event isn't being fired.
Chrome doesn't support mouse events on option elements.
Check this answer out
https://stackoverflow.com/a/48668859/8474551

onclick() and onblur() ordering issue

I have an input field that brings up a custom drop-down menu. I would like the following functionality:
When the user clicks anywhere outside the input field, the menu should be removed.
If, more specifically, the user clicks on a div inside the menu, the menu should be removed, and special processing should occur based on which div was clicked.
Here is my implementation:
The input field has an onblur() event which deletes the menu (by setting its parent's innerHTML to an empty string) whenever the user clicks outside the input field. The divs inside the menu also have onclick() events which execute the special processing.
The problem is that the onclick() events never fire when the menu is clicked, because the input field's onblur() fires first and deletes the menu, including the onclick()s!
I solved the problem by splitting the menu divs' onclick() into onmousedown() and onmouseup() events and setting a global flag on mouse down which is cleared on mouse up, similar to what was suggested in this answer. Because onmousedown() fires before onblur(), the flag will be set in onblur() if one of the menu divs was clicked, but not if somewhere else on the screen was. If the menu was clicked, I immediately return from onblur() without deleting the menu, then wait for the onclick() to fire, at which point I can safely delete the menu.
Is there a more elegant solution?
The code looks something like this:
<div class="menu" onmousedown="setFlag()" onmouseup="doProcessing()">...</div>
<input id="input" onblur="removeMenu()" ... />
var mouseflag;
function setFlag() {
mouseflag = true;
}
function removeMenu() {
if (!mouseflag) {
document.getElementById('menu').innerHTML = '';
}
}
function doProcessing(id, name) {
mouseflag = false;
...
}
I was having the exact same issue as you, my UI is designed exactly as you describe. I solved the problem by simply replacing the onClick for the menu items with an onMouseDown. I did nothing else; no onMouseUp, no flags. This resolved the problem by letting the browser automatically re-order based on the priority of these event handlers, without any additional work from me.
Is there any reason why this wouldn't have also worked for you?
onClick should not be replaced with onMouseDown.
While this approach somewhat works, the two are fundamentally different events that have different expectations in the eyes of the user. Using onMouseDown instead of onClick will ruin the predictability of your software in this case. Thus, the two events are noninterchangeable.
To illustrate: when accidentally clicking on a button, users expect to be able to hold down the mouse click, drag the cursor outside of the element, and release the mouse button, ultimately resulting in no action. onClick does this. onMouseDown doesn't allow the user to hold the mouse down, and instead will immediately trigger an action, without any recourse for the user. onClick is the standard by which we expect to trigger actions on a computer.
In this situation, call event.preventDefault() on the onMouseDown event. onMouseDown will cause a blur event by default, and will not do so when preventDefault is called. Then, onClick will have a chance to be called. A blur event will still happen, only after onClick.
After all, the onClick event is a combination of onMouseDown and onMouseUp, if and only if they both occur within the same element.
Replace on onmousedown with onfocus. So this event will be triggered when the focus is inside the textbox.
Replace on onmouseup with onblur. The moment you take out your focus out of textbox, onblur will execute.
I guess this is what you might need.
UPDATE:
when you execute your function onfocus-->remove the classes that you will apply in onblur and add the classes that you want to be executed onfocus
and
when you execute your function onblur-->remove the classes that you will apply in onfocus
and add the classes that you want to be executed onblur
I don't see any need of flag variables.
UPDATE 2:
You can use the events onmouseout and onmouseover
onmouseover-Detects when the cursor is over it.
onmouseout-Detects when the cursor leaves.
onFocus / onBlur are events that don't bubble. There are however focus events that do bubble. These being focusin and focusout.
Now to the solution: We wrap both the input and our dropdown into a div-element and set the tabindex of that div to -1 (so that it can recieve focus / but does not appear in the tab order). We now add an eventlistener for focusin and focusout to this div. And since these events do bubble a click on our input element will trigger our divs focusin event (which opens the drop-down)
The neat part now is that a click on our dropdown will also trigger the focusin event on our div (so we basically maintain focus which means: focusout/blur never fires and our dropdown stays open)
You can try this out with the code snippit below (the dropdown only closes on loss of focus - but if you want it to close when clicking on the dropdown aswell just uncomment the one line of JS)
const container = document.getElementById("container")
const dropDown = document.getElementById("drop-down")
container.addEventListener("focusin", (event) => {
dropDown.classList.toggle("hidden", false)
})
container.addEventListener("focusout", (event) => {
dropDown.classList.toggle("hidden", true)
})
dropDown.addEventListener("click", (event) => {
console.log("I - the drop down - have been clicked");
//dropDown.classList.toggle("hidden", true);
});
.container {
width: fit-content;
}
.drop-down {
width: 100%;
height: 200px;
border: solid 1px black
}
.hidden {
display: none
}
<div class="container" id="container" tabindex="-1">
<input id="input" />
<div class="drop-down hidden" id="drop-down" > Hi I'm a drop down </div>
</div>
there arises however one issue if you want to add your dropdown into the tabbing order, have buttons in your dropdown or in general have an element in the dropdown, that can recieve focus. Because then a click will give the element in the dropdown focus first. This triggers our container div to lose focus which closes the dropdown so the focus event can't bubble further and therefore can't trigger the focusin on our container.
We can solve this issue by expanding the focusout eventlistener a bit.
The new eventlistener is as follows:
container.addEventListener("focusout", (event) => {
dropDown.classList.toggle("hidden", !container.matches(":hover"))
})
We basically say: "don't you close that dropDown if someone is hovering over it" (This solution only considers mouse-use; but in that case this is fine, because the problem this tries to fix only ever occured when using a mouse, when tabbing onto/through the dropDown everything worked fine from the start)
change onclick by onfocus
even if the onblur and onclick do not get along very well, but obviously onfocus and yes onblur. since even after the menu is closed the onfocus is still valid for the element clicked inside.
I did and it worked.
An ideal solution I found to work for me was to simply add a timeout in my onBlur function. I used 250ms, that provided smooth behaviour for my blur event and allowed my onClick to fire before the onBlur. I used this example as a reference https://erikmartinjordan.com/onblur-prevents-onclick-react
You can use a setInterval function inside your onBlur handler, like this:
<input id="input" onblur="removeMenu()" ... />
function removeMenu() {
setInterval(function(){
if (!mouseflag) {
document.getElementById('menu').innerHTML = '';
}
}, 0);
}
the setInterval function will remove your onBlur function out from the call stack, add because you set time to 0, this function will be called immediately after other event handler finished

Why browser doesn't fire change event

I have
<input type="text" id="pies" value="" />
and
$( document ).ready(function() {
$('#pies').on('change', function() { alert('cham'); });
$('#pies').focus();
$('#pies').val('kooooo');
$('#pies').blur();
});
Why browser doesn't fire change event? How can I make that browser will fire change event. I don't want to trigger "change" manually, because if I will trigger change, in some cases trigger change will be triggered twice. This is only example.
Call the change using :
$('#pies').change();
You have to do it manually
$('#pies').change();
As docs says
The change event is sent to an element when its value changes. This event is limited to elements, boxes and elements. For select boxes, checkboxes, and radio buttons, the event is fired immediately when the user makes a selection with the mouse, but for the other element types the event is deferred until the element loses focus.
In auto complete case try to do $("#pies").trigger("autocompleteselect");
Better use keypress instead of change

Why does dynamically changing a checkbox not trigger a form change event?

I wrote this snippet of javascript/jQuery to change a check box.
http://jsfiddle.net/johnhoffman/crF93/
Javascript
$(function() {
$("a").click(function() {
if ($("input[type='checkbox']").attr('checked') == "checked")
$("input[type='checkbox']").removeAttr('checked');
else
$("input[type='checkbox']").attr('checked', 'checked');
return false;
});
$("input[type='checkbox']").change(function(){
console.log("Checkbox changed.");
});
});​
HTML
<input type="checkbox" />
Change CheckBox​
Interestingly, clicking the link alters the text box, but does not trigger the form change event that calls the function that logs a message in Chrome Web Developer Console. Why? How do I make it do that?
You need to trigger the change event, .trigger('change'), so that event knows that a change took place.
From http://api.jquery.com/change/:
Description: Bind an event handler to the "change" JavaScript event, or trigger that event on an element.
This method is a shortcut for .on( "change", handler ) in the first two variations, and .trigger( "change" ) in the third.
The change event is sent to an element when its value changes. This event is limited to <input> elements, <textarea> boxes and <select> elements. For select boxes, checkboxes, and radio buttons, the event is fired immediately when the user makes a selection with the mouse, but for the other element types the event is deferred until the element loses focus.
Demo:
http://jsfiddle.net/nPkPw/3/
Using chaining: http://jsfiddle.net/nPkPw/5/
i.e. $("input[type='checkbox']").trigger('change').attr('checked', 'checked');
This isn't surprising, but I guess you could as this to the list of non-effect in the msdn.
"This event is fired when the contents are committed and not while
the value is changing."
"The onchange event does not fire when the
selected option of the select object is changed programmatically."
You could always just .click() it jsFiddle

jQuery blur handler not working on div element?

I don't understand why the jQuery blur handler isn't working in the most simple case. I'm literally creating a div 100px by 100px and setting a blur event on it, but it's not firing (JSFiddle):
<div id="test">this is a test</div>
$(document).ready(function() {
$('#test').bind('blur', function() {
alert('blur event!');
});
});
Is my understanding of blur wrong? I expect the blur event to fire when I click anywhere that is not the div...right?
According to jQuery's documentation:
In recent browsers, the domain of the event has been extended to
include all element types. An element can lose focus via keyboard
commands, such as the Tab key, or by mouse clicks elsewhere on the
page.
I've tried it on the latest Chrome and Firefox on Mac.
From the W3C DOM Events specification:
focus
The focus event occurs when an element receives focus either via a pointing device or by
tabbing navigation. This event is valid for the following elements: LABEL, INPUT, SELECT,
TEXTAREA, and BUTTON.
blur
The blur event occurs when an element loses focus either via the pointing device or by
tabbing navigation. This event is valid for the following elements: LABEL, INPUT, SELECT,
TEXTAREA, and BUTTON.
The jQuery docs state browsers extended the events to other elements, which I'm guessing means blur and focus are aliases for the more generic DOMFocusIn and DOMFocusOut events. Non-input elements aren't eligible to receive those by default though, and an element has to somehow gain focus before losing it - a blur still won't fire for every click outside the div.
This SO question mentions that giving an element a tabindex would allow that, and seems to work for me in Chrome after modifying your jsFiddle. (Albeit with a fairly ugly outline.)
As far as I knew, blur happens on inputs that had the focus, either way you say
I expect the blur event to fire when I click anywhere that is not the div...right?
Not exactly, the blur event only happens for an element that had the focus first
So in order for a blur event to occur, you would first have to give focus to the div, how is the div getting focus first?
If you are really try to determine if there was a click outside of your div, you need to attach a click handler to the document, and then check to see where your click came from.
var div_id = "#my_div";
var outsideDivClick = function (event) {
var target = event.target || event.srcElement;
var box = jQuery(div_id);
do {
if (box[0] == target) {
// Click occured inside the box, do nothing.
return;
}
target = target.parentNode;
} while (target);
}
jQuery(document).click(outsideDivClick);
Just remember that this handler will be run for EVERY click on the page. (in the past if i ha to use something like this, i attach the handler when I need it, and remove it when I no longer need to look for it)
A can't "blur" because that would involve the div having focus in the first place. Non-input elements like a and textarea can have focus, which is what jQuery's documentation refers to.
What you need is the "mouseout" or "mouseleave" event (mouseleave doesn't bubble, mouseout does), which will be fired when the cursor leaves the div. If you need to have clicks, I would attach a "click" event to the body, as well as the div and stopping the event propagation on only the div:
$("div").click(function(e) {
return false; // stop propagation
});
Or, if you're really determined, you can fake the appearance of a div with a and some CSS rules :)
If you want something to happen while you move your mouse over the box, you could use the mouseover event.

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