Develop Reference

Javascript - simplifying a bunch of long repetative hide/show functions

Things have gotten out of hand for me. What started off as the simplest solution has ballooned to the point where it is no longer manageable. I need to come up with a way to simplify a process.
Currently I have a map with pins denoting specific countries world-wide. As the mouse hovers over a pin, a hidden div appears. When you mouse over another one, the previous div disappears and a new one opens. I started with like 5 of these and it wasn't an issue but I keep getting requests for more and want to manage the script in a different way now.
$('#PH1').mouseenter(function () {
$('#BO2').hide();
$('#US2').hide();
$('#UK2').hide();
$('#CH2').hide();
$('#BZ2').hide();
$('#QC2').hide();
$('#OT2').hide();
$('#VA2').hide();
$('#RU2').hide();
$('#JT2').hide();
$('#HK2').hide();
$('#SH2').hide();
$('#BJ2').hide();
$('#XI2').hide();
$('#BE2').hide();
$('#AT2').hide();
$('#FR2').hide();
$('#MX2').hide();
$('#PH2').show();
});
$('#PH1').click(function (e) {
e.stopPropagation();
});
$('#mint').click(function () {
$('#PH2').hide();
});
In this instance div id #PH1 is the pin, when the mouse enters the div it hides all of the other div's #**2 and displays the one related to #PH1, which is #PH2
This list is repeated for each DIV. Every time I need to add a new DIV I need to make each existing list longer as well as create a new one. How can this process be made much simpler?

Thats not a right way to do this, you should use classes for this. But their is a wayaround for this all you need to is add a class add class ele1 to all #**1 and ele2 to all #**2:
then
$('.ele1').mouseenter(function () {
$(".ele2").hide();
var id = this.id;
var newId = id.substring(0,2)+"2";
$("#"+newId).show();
});

Make a loop:
var all= ['#BO2', '#US2', '#UK2', '#CH2', '#BZ2', '#QC2', '#OT2', '#VA2', '#RU2', '#JT2', '#HK2', '#SH2', '#BJ2', '#XI2' , '#BE2', '#AT2', '#FR2', '#MX2', '#PH2']
all.forEach(function (i){
$(i).hide();
});

Use a class selector on all of the DIVs you want to hide/show instead of an ID.
First, add a shared class to all DIVs so we target all of them by class.
HTML: class="hidden-divs"
jQuery: $('.hidden-divs').hide();
Then show the relevant DIV.
$('#PH2').show();
Using your first example, it would look like this:
$('#PH1').mouseenter(function () {
$('.hidden-divs').hide();
$('#PH2').show();
});

You can use jquery to hide multiple divs if you can select them. For example, suppose you have a common class ".map_divs" on all your divs, you could easily do:
$(".map_divs").hide();
On a side-note, you could solve all this on CSS, using :hover. For example:
.map_divs:hover {
display: block;
}

If you can edit the div's yourself (if it is not generated by a library) I would do it like this.
Add a common class to all your divs. Then on each div, add a data attribtue to the related id.
<div class="pin" id="PH1" data-rel="PH2"></div>
Then you can have a simple function like this:
$(".pin").mouseenter(function() {
var relatedId = $(this).data("rel");
$(".pin[id$='2']").hide(); // Hide all pins with id ending in 2
$("#" + relatedId).show() //show PH2
})

Using classes might be a better option here. You can then just attach the mouseenter event on document ready to all pins. This will work for an infinite number of pins too.
$('.pin').mouseenter(function () {
$('.popup').removeClass('show');
var id = this.id.split('_')[1];
$('#popup_' + id).addClass('show');
});
.pin {
width:30px;
height:30px;
margin-bottom:20px;
background-color:red;
}
.popup {
display:none;
width:100px;
height:100px;
margin-bottom:20px;
background-color:blue;
}
.popup.show {
display:block;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="pin_1" class="pin"></div>
<div id="popup_1" class="popup"></div>
<div id="pin_2" class="pin"></div>
<div id="popup_2" class="popup"></div>

If your div element is ordered like below, you can get the same result using css only, which will increase speed and overall experience (especially on phones and tablets).
When "hover" the yellow squares, the popup will be visibible even when "hover" the popup.
.pin {
width:30px;
height:30px;
margin-bottom:20px;
background-color:red;
}
.popup {
display:none;
width:100px;
height:100px;
margin-bottom:20px;
background-color:blue;
}
.pin:hover + .popup {
display:block;
}
.pin.type2 {
background-color:yellow;
}
.pin.type2:hover .popup {
display: inline-block;
margin-top: 30px;
}
<div id="pin_1" class="pin"></div>
<div id="popup_1" class="popup"></div>
<div id="pin_2" class="pin"></div>
<div id="popup_2" class="popup"></div>
<div id="pin_3" class="pin type2"><div id="popup_3" class="popup"></div></div>
<div id="pin_4" class="pin type2"><div id="popup_4" class="popup"></div></div>

Run function after .append

I'm having the following html code:
<div>
<div id="a"></div>
</div>
When the div with id="a" is clicked, I want to replace this div with the following div:
<div id="b"></div>
I managed to create the following fiddle: http://jsfiddle.net/ucant5uy/
In this fiddle, you can see that the first function (#a is clicked) runs perfect, but the second function (#b is clicked) doesn't run, because the div #b doesn't exist when the page is loaded.
Then I decided to put the second function inside the first function: http://jsfiddle.net/ucant5uy/2/. As you can see, you can click #a once, and #b once, and then the code stops working. I want to be able to click #a and #b as many times as I would like to. I know you can achieve this with some simple CSS tricks (adding both divs to the HTML and using display:none;), but I'm wondering wether it's possible to achieve the same thing using .append().
Thanks in advance!

You should bind the function to the parent div (and it is as main), which exist in the DOM and will exist, otherwise you can assign the function only to the elements, which already exist in DOM.
$(document).ready(function() {
$('#main').on("click","#a",function() {
$(this).parent().append('<div id="b"></div>');
$(this).remove();
})
$('#main').on("click","#b",function() {
$(this).parent().append('<div id="a"></div>');
$(this).remove();
})
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="main">
<div id="a"></div>
</div>

use .on() for future elements event handler
$("div").on('click','div#b',function() {
$(this).parent().append('<div id="a"></div>');
$(this).remove();
})
Demo:
$(document).ready(function() {
$("div").on('click','div#a',function() {
$(this).parent().append('<div id="b"></div>');
$(this).remove();
})
$("div").on('click','div#b',function() {
$(this).parent().append('<div id="a"></div>');
$(this).remove();
})
});
div {
width:200px;
height:200px;
background:red;
}
#a, #b {
width:100px;
height:100px;
}
#a {
background-color:green;
}
#b {
background-color:blue;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div>
<div id="a"></div>
</div>

jQuery binding events to elements with dynamic class

I have a trigger element and a responding element.
<div class="more"></div>
<div class="info"></div>
I would like to bind an open/close type event.
$('.more').delegate($('.more'), 'click', function(){
$(this).removeClass('more');
$(this).addClass('less');
$(this).text("less...");
$('.info').addClass("open");
});
$('.less').delegate($('.less'), 'click', function(){
$(this).addClass('more');
$(this).removeClass('less');
$(this).text("more...");
$('.info').removeClass("open");
});
It doesn't work as intended, if the second function is nested in the first then you can open and close only once.
If the script is formatted sensibly as above it will open but not close.
Could anyone help me out?
Bonus if the script could support the .info could be either a sibling or the element immediately following $(.more/.less)'s parent.
I've been toying with .on/.live/.bind but less successfully than above.

Use event delegation ,and binded to document or immediate parent,not same element
$(document).on( 'click',".more", function(){
$(this).removeClass('more');
$(this).addClass('less');
$(this).text("less...");
$('.info').addClass("open");
});
$(document).on('click',".less", function(){
$(this).addClass('more');
$(this).removeClass('less');
$(this).text("more...");
$('.info').removeClass("open");
});
DEMO
NOTE: delegate was outdated with latest version of jquery ,so use on instead,
ISSUE: you are delegated with same element $('.less'),$('.more') use immediate parent or document

Just use JavaScript to toggle a class, and let CSS magic do the rest. Here is a demo: http://jsfiddle.net/pomeh/69sX5/1/
And here is the code:
HTML
<div>
Some visible content
</div>
<div class="content-fold">
<div class="more">More...</div>
<div class="less">Less...</div>
</div>
<div class="info">Some hidden additional content</div>
CSS
/* Additional content and Less button hidden by default */
.content-fold + .info, .content-fold .less {
display: none;
}
/* Additional content and Less button shown when class shown is active */
.content-fold.shown + .info, .content-fold.shown .less {
display: block;
}
/* More button hidden when additional content is shown */
.content-fold.shown .more {
display: none;
}
/*
You can also move the "div.info" into the "div.content-fold",
and use ".content-fold.shown > .info" instead of ".content-fold.shown + .info"
Browser support is quite good for adjacent selector (see http://www.quirksmode.org/css/selectors/#t11 and https://developer.mozilla.org/en-US/docs/Web/CSS/Adjacent_sibling_selectors#Browser_compatibility)
*/
JavaScript
$('.content-fold').on('click', function(){
$(this).toggleClass('shown');
});

Use id to do your task. it's easy.
Html
<div class="more" id="toggle"></div>
<div class="info"></div>
Jquery
$('#toggle').click(function(){
var $this = $(this) //store object
if($this.hasClass('more')) {
$this.removeClass('more').addClass('less').text('Less...')
$this.next('.info').addClass('open');
} else {
$this.removeClass('less').addClass('more').text('More...')
$this.next('.info').removeClass('open');
}
});
js Fiddle: http://jsfiddle.net/5N6TL/53/

Display element only if another element exists

How would I go about hiding a div and only displaying it if another div existed on a page? I'm guessing jquery or js would be the way to go....
<style type="text/css">
.always-here {
display:none;
}
</style>
<div class="im-here">This div exists on this particular page!</div>
<div class="always-here">This div is always here but has the style
display: none unless a div with the class "im-here" exists.</div>

For your current current html you can do
.always-here {
display:none;
}
.im-here ~ .always-here{
display:block;
}
this will only work if .always-here and .im-here are siblings and .im-here comes before.
http://jsfiddle.net/BKYSV/ - .im-here present
http://jsfiddle.net/BKYSV/1/ - .im-here absent

$(document).ready(function(){
if($(".im-here").length > 0)
{
$(".always-here").show();
}
});
here is the code
Click Here!

Try this:
if($(".im-here").length)
$(".always-here").show();

How to show the child div on mouse hover of parent div

I have a number of parent divs (.parent_div), which each contain a child div (.hotqcontent) where I output data from my database using a loop.
The following is my current markup:
<div class="content">
<div class="parent_div">
<div class="hotqcontent">
content of first div goes here...
</div>
<hr>
</div>
<div class="parent_div">
<div class="hotqcontent">
content of second div goes here...
</div>
<hr>
</div>
<div class="parent_div">
<div class="hotqcontent">
content of third div goes here...
</div>
<hr>
</div>
<div class="parent_div">
<div class="hotqcontent">
content of fourth div goes here...
</div>
<hr>
</div>
</div>
What I would like to achieve is when a user hovers / mouseovers a parent div, the contents of the child div contained within should be revealed.
To achieve this I wrote the following jQuery script but it doesn't appear to be working. It's not even showing the alert!
<script>
$(document).ready(function() {
$(function() {
$('.parent_div').hover(function() {
alert("hello");
$('.hotqcontent').toggle();
});
});
});
</script>
How can I modify or replace my existing code to achieve the desired output?

If you want pure CSS than you can do it like this....
In the CSS below, on initialization/page load, I am hiding child element using display: none; and then on hover of the parent element, say having a class parent_div, I use display: block; to unhide the element.
.hotqcontent {
display: none;
/* I assume you'll need display: none; on initialization */
}
.parent_div:hover .hotqcontent {
/* This selector will apply styles to hotqcontent when parent_div will be hovered */
display: block;
/* Other styles goes here */
}
Demo

Try this
$(document).ready(function() {
$('.parent_div').hover(function() {
alert("hello");
$(this).find('.hotqcontent').toggle();
});
});
Or
$(function() {
$('.parent_div').hover(function() {
alert("hello");
$(this).find('.hotqcontent').toggle();
});
});

You can use css for this,
.parent_div:hover .hotqcontent {display:block;}

This can be done with pure css (I've added a couple of bits in just to make it a bit neater for the JSFIDDLE):
.parent_div {
height: 50px;
background-color:#ff0000;
margin-top: 10px;
}
.parent_div .hotqcontent {
display: none;
}
.parent_div:hover .hotqcontent {
display:block;
}
This will ensure that your site still functions in the same way if users have Javascript disabled.
Demonstration:
http://jsfiddle.net/jezzipin/LDchj/

With .hotqcontent you are selecting every element with this class. But you want to select only the .hotqcontent element underneath the parent.
$('.hotqcontent', this).toggle();

$(document).ready(function(){
$('.parent_div').on('mouseover',function(){
$(this).children('.hotqcontent').show();
}).on('mouseout',function(){
$(this).children('.hotqcontent').hide();
});;
});
JSFIDDLE

you don't need document.ready function inside document.ready..
try this
$(function() { //<--this is shorthand for document.ready
$('.parent_div').hover(function() {
alert("hello");
$(this).find('.hotqcontent').toggle();
//or
$(this).children().toggle();
});
});
and yes your code will toggle all div with class hotqcontent..(which i think you don't need this) anyways if you want to toggle that particular div then use this reference to toggle that particular div
updated
you can use on delegated event for dynamically generated elements
$(function() { //<--this is shorthand for document.ready
$('.content').on('mouseenter','.parent_div',function() {
alert("hello");
$(this).find('.hotqcontent').toggle();
//or
$(this).children().toggle();
});
});

you can try this:
jQuery(document).ready(function() {
jQuery("div.hotqcontent").css('display','none');
jQuery("div.parent_div").each(function(){
jQuery(this).hover(function(){
jQuery(this).children("div.hotqcontent").show(200);
}, function(){
jQuery(this).children("div.hotqcontent").hide(200);
});
});
});