Develop Reference

jquery slideDown, slideUp wiggling

I am new to jquery and have problem with one part of my script. basically I am making dropdown div when mouse is over the button, but div starts moving up and down like crazy. here is what i have done: `
<script type="text/javascript">
public var boolean opened = false;
$("#drop1").slideUp();
$("#first").mouseover(function(){
$("#drop1").slideDown();
});
$("#first").mouseout(function(){
$("#drop1").slideUp();
});
});
also I tried using boolean variable but it gives me error.
<script type="text/javascript">
$(document).ready(function(){
public var boolean opened = false;
$("#drop1").slideUp();
$("#first").mouseover(function(){
if(!opened){
$("#drop1").slideDown();
opened = true;
}
});
$("#first").mouseout(function(){
if(opened){
$("#drop1").slideUp();
opened = false;
}
});
});
here is HTML if you want, but I think there is everything ok.
<link rel="stylesheet" type="text/css" href="design.css">
<div id="first" style="position: absolute; left: 0px;">
<a class="btn" href = "TheShooter/Launcher.exe" ><b>LAN shooter project</b></a>
<div id="drop1">
<em>shooter project main page</em> <br/>
info: Local Area Network multiplayer game, made with unity. Project not finished yet, but sometimes fun to play. <br/>
controls: walking: w,a,s,d<br/>
shoot: LMB.<br/>
zoom: RMB.
</div>
</div>
Thanks for any help.
--Nick.

So it looks like you might be more used to strongly typed languages like C#. JavaScript and its library jQuery are loosely typed, meaning you don't declare scope or type. Here's your code above cleaned up a bit to use correct syntax and solve the issues you're seeing:
$(document).ready(function(){
var opened = false;
// Instead of sliding this up, give the #drop1 element
// a property of display: none; to start - then remove the line below
$("#drop1").slideUp();
$("#first").mouseover(function(){
if(!opened){
// Below, I'm using a callback, which means the boolean
// won't update to true until after the animation is finished
$("#drop1").slideDown(400, function() {
opened = true;
});
}
})// Since it's the same element, we can chain events
.mouseout(function(){
if(opened){
// Another callback
$("#drop1").slideUp(400, function() {
opened = false;
});
}
}
});
});
Let me know if you have any questions about the above!

Hi please refer this fiddle which should answer your question. No need to add any boolean or conditional checking:
<div id="wrap">
<div id="text">text</div>
<div id="video">video</div>
and js
$(document).ready(function(){
$("#wrap").mouseover(function(){
$("#video").stop().slideDown("slow");
});
$("#wrap").mouseout(function(){
$("#video").slideUp("slow");
});
});
and css
#text
{
margin-top:20px;
float:center;
font:VNF-Museo;
font-size:40px;
color: #333;
margin-left:auto;
margin-right:auto;
border: 1px solid #000;
}
#video
{
display:none;
width:1024px;
height:278px;
border: 1px solid #000;
}

I think you should try something like this:
$(document).ready(function() {
$("#first").mouseover(function(){
$("#drop1").slideDown("slow");
});
$("#first").mouseout(function(){
$("#drop1").slideUp("slow");
});
});
See this example above, from the jQuery offical documentation, for more information:
http://api.jquery.com/mouseover/
http://api.jquery.com/mouseout/

Here is one more answer with live example,
$(document).ready(function(){
$("#drop1").mouseover(function(){
$("#first").slideDown("slow");
});
$("#drop1").mouseout(function(){
$("#first").slideUp("slow");
});
});
#first, #drop1 {
padding: 5px;
text-align: center;
background-color: #acacac;
border: solid 1px #c3c3c3;
}
#first {
padding: 50px;
display: none;
background-color: skyblue;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.2/jquery.min.js"></script>
<div id="drop1">Mouse over on panel to slide down</div>
<div id="first">Hello Stackoverflow ..!</div>

JQuery:Selecting second element in case element with same ID exists

I know it's not a good practice to use same id for different element , but in a case I am forced to use same id for two different elements ( which will be automatically generated in the original program)
I'm trying to select the second element with the same id ( or when scaling say , nth element ).
Is there a way to do this ?
I have created a code snippet here , that shows the problem.
$("#btn").click(function(){
$("#test").css("background","blue");
});
#test {
height: 100px;
width: 100px;
border: 1px solid #ccc;
margin:10px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="test">
</div>
<div id="test">
</div>
<button id="btn">Click Me</button>

You must not have duplicate ids but if you can not do that you can use Attribute Equals Selector [name=”value”] with :eq(index). The :eq takes the index of element of the collection. You may also want to use background-color.
Live Demo
$("[id=test]:eq(1)").css("background-color","blue");

Try using the data-id attribute instead since duplicate ids can produce unpredictable behaviour.
$("#btn").click(function(){
$("[data-id='test']:eq(1)").css("background","blue");
});
[data-id='test'] {
height: 100px;
width: 100px;
border: 1px solid #ccc;
margin:10px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div data-id="test">
</div>
<div data-id="test">
</div>
<button id="btn">Click Me</button>

$("#test:eq(1)").css("background-color","blue");

jQuery .is(":disabled") - Why doesn't this work?

http://jsfiddle.net/hw4bz89k/
Why doesn't the following return 'true'? I know I must be missing something elementary.
var test = $("#test");
test.prop("disabled", true);
alert(test.is(":disabled"));
#test {
width: 100px;
height: 50px;
background-color: red;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script>
<div id="test"></div>

You cannot disable a <div> element.
From the jQuery doc for :disable
The :disabled selector should only be used for selecting HTML elements that support the disabled attribute (<button>, <input>, <optgroup>, <option>, <select>, and <textarea>).

How to use JavaScript to Alter CSS for Multiple Elements

I am trying to use JavaScript to change the background color of an element after being selected, and also to make sure that only one element at a time has the particular background color. Once the user selects on a different element I would like the previous element that was selected to be replaced by a different background color. Currently I am only able to toggle individual elements by selecting on EACH element. I need to be able to select on an element and apply the new background color, then have JavaScript change the background color of the previously active element to a different color (one less click).
What I am trying to do is very similar to modern navbars or list items where only one element at a time is “active” and has a background color that is different than the other elements in the same div, row, etc.
Notes about my work I am utilizing bootstrap and have no desire to use jQuery for this particular project.
CSS:
<!DOCTYPE html>
<html lang="en">
<head>
<style>
h4 {
border: 1px solid black;
border-radius: 8px;
padding: 10px 2px 10px 2px;
margin: 20px 20px 0px 20px;
background-color: #F0F0F0;
border-color: #F8F8F8;
color: #505050;
cursor: pointer;
}
.active {
background-color: #99E6FF;
}
</style>
</head>
</html>
HTML:
<div id="pTwoRowOne">
<div class="row">
<div class="col-md-4 row row-centered">
<h4 id="techBio" class="test">Biology</h4>
</div>
<div class="col-md-4 row row-centered">
<h4 id="techCart" class="test">Cartography</h4>
</div>
<div class="col-md-4 row row-centered">
<h4 id="techChem" class="test">Chemistry</h4>
</div>
</div>
</div>
JavaScript:
document.getElementById("techBio").onclick=function() {
document.getElementById("techBio").classList.toggle('active');
}
document.getElementById("techCart").onclick=function() {
document.getElementById("techCart").classList.toggle('active');
}
document.getElementById("techChem").onclick=function() {
document.getElementById("techChem").classList.toggle('active');
}
An example can be seen here: http://jsbin.com/fugogarove/1/edit?html,css,js,output
If clarification is needed let me know.

Yup, pretty straightforward.
Assumptions
You're not trying to support IE8, since you're using classList
You're okay with housing your elements as variables as opposed to repeatedly querying the DOM.
Example
JSBin
Code
I rewrote your JavaScript to make it a little bit cleaner and to DRY it up a bit:
var techs = [].slice.call(document.querySelectorAll('#pTwoRowOne h4'));
function set_active(event) {
techs.forEach(function(tech){
if (event.target == tech) { return; }
tech.classList.remove('active');
});
event.target.classList.toggle('active');
}
techs.forEach(function(item) {
item.addEventListener('click', set_active);
});
Some explanation
[].slice.call(document.querySelectorAll('#pTwoRowOne h4')); – We're using this to change the output from a NodeList to an Array. This allows us to use forEach later. querySelectorAll returns a NodeList that contains all elements matching the CSS selector. You can probably replace that with a better CSS selector depending on your environment.
addEventListener is a much nicer way than the iterative add via onclick += to bind an event listener. It's also the recommended way (as far as I know) in ECMA5 and later.
By setting the element queries as variables, you'll be able to keep the reference in memory instead of polling the DOM every time to alter elements. That'll make your JavaScript marginally faster, and it's again just a nicer, cleaner version of the code which it produces.
updates
I reworked the JS to make more sense.

Assuming you only ever have one active element, you can find it using document.querySelector() - if you can have multiples you can use document.querySelectorAll() and iterate through them.
Simple case:
function activate(event) {
var active=document.querySelector('.active');
// activate the clicked element (even if it was already active)
event.target.classList.add('active');
// deactivate the previously-active element (even if it was the clicked one => toggle)
if (active) active.classList.remove('active');
}
document.getElementById("techBio").addEventListener("click",activate);
document.getElementById("techCart").addEventListener("click",activate);
document.getElementById("techChem").addEventListener("click",activate);
h4 {
border: 1px solid black;
border-radius: 8px;
padding: 10px 2px 10px 2px;
margin: 20px 20px 0px 20px;
background-color: #F0F0F0;
border-color: #F8F8F8;
color: #505050;
cursor: pointer;
}
.active {
background-color: #99E6FF;
}
<div id="pTwoRowOne">
<div class="row">
<div class="col-md-4 row row-centered">
<h4 id="techBio" class="test">Biology</h4>
</div>
<div class="col-md-4 row row-centered">
<h4 id="techCart" class="test">Cartography</h4>
</div>
<div class="col-md-4 row row-centered">
<h4 id="techChem" class="test">Chemistry</h4>
</div>
</div>
</div>

Another similar yet simpler way to do it: jsBin ;)
var H4 = document.getElementsByClassName("test"), act;
[].forEach.call(H4, function(el){
el.addEventListener("click", function(){
if(act) act.classList.remove("active");
return (this.classList.toggle("active"), act=this);
});
});

You can do something like this:
[].slice.call(document.querySelectorAll(".test")).forEach(function(element) {
element.addEventListener('click', function(event) {
if (activeElement = document.querySelector(".test.active")) {
activeElement.classList.remove("active");
};
event.target.classList.add('active');
});
});
Basically, first we remove the active class from the active element, then we add it to the target.
JSBin

How to move an element into another element

I would like to move one DIV element inside another. For example, I want to move this (including all children):
<div id="source">
...
</div>
into this:
<div id="destination">
...
</div>
so that I have this:
<div id="destination">
<div id="source">
...
</div>
</div>

You may want to use the appendTo function (which adds to the end of the element):
$("#source").appendTo("#destination");
Alternatively you could use the prependTo function (which adds to the beginning of the element):
$("#source").prependTo("#destination");
Example:
$("#appendTo").click(function() {
$("#moveMeIntoMain").appendTo($("#main"));
});
$("#prependTo").click(function() {
$("#moveMeIntoMain").prependTo($("#main"));
});
#main {
border: 2px solid blue;
min-height: 100px;
}
.moveMeIntoMain {
border: 1px solid red;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="main">main</div>
<div id="moveMeIntoMain" class="moveMeIntoMain">move me to main</div>
<button id="appendTo">appendTo main</button>
<button id="prependTo">prependTo main</button>

My solution:
Move:
jQuery("#NodesToMove").detach().appendTo('#DestinationContainerNode')
copy:
jQuery("#NodesToMove").appendTo('#DestinationContainerNode')
Note the usage of .detach(). When copying, be careful that you are not duplicating IDs.

Use a vanilla JavaScript solution:
// Declare a fragment:
var fragment = document.createDocumentFragment();
// Append desired element to the fragment:
fragment.appendChild(document.getElementById('source'));
// Append fragment to desired element:
document.getElementById('destination').appendChild(fragment);
Check it out.

Try plain JavaScript: destination.appendChild(source);.
onclick = function(){ destination.appendChild(source) };
div {
margin: .1em;
}
#destination {
border: solid 1px red;
}
#source {
border: solid 1px gray;
}
<div id=destination>
###
</div>
<div id=source>
***
</div>

I just used:
$('#source').prependTo('#destination');
Which I grabbed from here.

If the div where you want to put your element has content inside, and you want the element to show after the main content:
$("#destination").append($("#source"));
If the div where you want to put your element has content inside, and you want to show the element before the main content:
$("#destination").prepend($("#source"));
If the div where you want to put your element is empty, or you want to replace it entirely:
$("#element").html('<div id="source">...</div>');
If you want to duplicate an element before any of the above:
$("#destination").append($("#source").clone());
// etc.

You can use:
To insert after,
jQuery("#source").insertAfter("#destination");
To insert inside another element,
jQuery("#source").appendTo("#destination");

You can use the following code to move the source to the destination:
jQuery("#source")
.detach()
.appendTo('#destination');
Try the working CodePen.
function move() {
jQuery("#source")
.detach()
.appendTo('#destination');
}
#source{
background-color: red;
color: #ffffff;
display: inline-block;
padding: 35px;
}
#destination{
background-color:blue;
color: #ffffff;
display: inline-block;
padding: 50px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="source">
I am source
</div>
<div id="destination">
I am destination
</div>
<button onclick="move();">Move</button>

If you want a quick demo and more details about how you move elements, try this link:
http://html-tuts.com/move-div-in-another-div-with-jquery
Here is a short example:
To move ABOVE an element:
$('.whatToMove').insertBefore('.whereToMove');
To move AFTER an element:
$('.whatToMove').insertAfter('.whereToMove');
To move inside an element, ABOVE ALL elements inside that container:
$('.whatToMove').prependTo('.whereToMove');
To move inside an element, AFTER ALL elements inside that container:
$('.whatToMove').appendTo('.whereToMove');

I need to move content from one container to another including all the event listeners. jQuery doesn't have a way to do it, but the standard DOM function appendChild does.
// Assuming only one .source and one .target
$('.source').on('click',function(){console.log('I am clicked');});
$('.target')[0].appendChild($('.source')[0]);
Using appendChild removes the .source* and places it into target including its event listeners: Node.appendChild() (MDN)

You may also try:
$("#destination").html($("#source"))
But this will completely overwrite anything you have in #destination.

You can use pure JavaScript, using appendChild() method...
The appendChild() method appends a node as the last child of a node.
Tip: If you want to create a new paragraph, with text, remember to
create the text as a Text node which you append to the paragraph, then
append the paragraph to the document.
You can also use this method to move an element from one element to
another.
Tip: Use the insertBefore() method to insert a new child node before a
specified, existing, child node.
So you can do that to do the job, this is what I created for you, using appendChild(), run and see how it works for your case:
function appendIt() {
var source = document.getElementById("source");
document.getElementById("destination").appendChild(source);
}
#source {
color: white;
background: green;
padding: 4px 8px;
}
#destination {
color: white;
background: red;
padding: 4px 8px;
}
button {
margin-top: 20px;
}
<div id="source">
<p>Source</p>
</div>
<div id="destination">
<p>Destination</p>
</div>
<button onclick="appendIt()">Move Element</button>

I noticed huge memory leak & performance difference between insertAfter & after or insertBefore & before .. If you have tons of DOM elements, or you need to use after() or before() inside a MouseMove event, the browser memory will probably increase and next operations will run really slow.
The solution I've just experienced is to use inserBefore instead before() and insertAfter instead after().

Dirty size improvement of Bekim Bacaj's answer:
div { border: 1px solid ; margin: 5px }
<div id="source" onclick="destination.appendChild(this)">click me</div>
<div id="destination" >...</div>

For the sake of completeness, there is another approach wrap() or wrapAll() mentioned in this article. So the OP's question could possibly be solved by this (that is, assuming the <div id="destination" /> does not yet exist, the following approach will create such a wrapper from scratch - the OP was not clear about whether the wrapper already exists or not):
$("#source").wrap('<div id="destination" />')
// or
$(".source").wrapAll('<div id="destination" />')
It sounds promising. However, when I was trying to do $("[id^=row]").wrapAll("<fieldset></fieldset>") on multiple nested structure like this:
<div id="row1">
<label>Name</label>
<input ...>
</div>
It correctly wraps those <div>...</div> and <input>...</input> BUT SOMEHOW LEAVES OUT the <label>...</label>. So I ended up use the explicit $("row1").append("#a_predefined_fieldset") instead. So, YMMV.

The .appendChild does precisely that - basically a cut& paste.
It moves the selected element and all of its child nodes.