Develop Reference

jQuery nested functions

I am still new to JavaScript and jQuery, so I am confused as to why the following code is not working as I anticipated. All I am trying to do is save input on a button click (id=recordInput) and display it with another button click (id=displayInput). What I observe is that tempInput is stored, (the code works until that point) but assignment of displayInputs onclick attribute is not executed. My question is, can you not nest a $().click() call inside of another &().click() call?
<script>
$(document).ready(function () {
$('#recordInput').click(function(event) {
var tempInput = $('#testInput').val();
&('#displayInput').click(function(event) {
console.log(tempInput);
});
});
});
</script>
My thinking is this in pseudocode:
assign recordInput onclick attribute to the following function:
store tempInput
set displayInput onclick to alert the tempInput value
what is wrong with my thinking?
NOTE: I did not include any html tags but all of the ids are referenced correctly

It's not working because you have put & instead of $ here
$('#displayInput').click(function(event) {
Fixing this may work, but you shouldn't set event handlers this way. Because every time your first handler function is called it will set an event handler for the second one. You can try with your console.log and you will see that the number of console.log is increasing by every click on #recordInput. So you should better set it like this :
var tempInput;
$('#recordInput').click(function(event) {
tempInput = $('#testInput').val();
});
$('#displayInput').click(function(event) {
console.log(tempInput);
});

I would change
$(document).ready(function () {
$('#recordInput').click(function(event) {
var tempInput = $('#testInput').val();
&('#displayInput').click(function(event) {
console.log(tempInput);
});
});
});
to
$(function(){
var testInput = '';
$('#recordInput').click(function(){
testInput = $('#testInput').val();
});
$('#displayInput').click(function(){
if(testInput !== ''){
console.log(testInput);
}
});
});
You are using & instead of $. Of course, you don't have to format the code exactly like I did.

2 anchor with one click

So here is my code
prev
prev
How do I make it both click if I click any of it ?
If I click .slider-1-prev, at the same I click .slider-2-prev
If I click .slider-2-prev, at the same I click .slider-2-prev
How to make it by javascript ?

As well as triggering the event on the other link, you need to shield against infinite repeating (e.g. with a shield variable):
var inClick = false;
$(document).ready(function {
$('.slider-1-prev').on('click', function {
if (!inClick) {
inClick = true;
$('.slider-2-prev').trigger('click');
inClick = false;
}
});
$('.slider-2-prev').on('click', function {
if (!inClick) {
inClick = true;
$('.slider-1-prev').trigger('click');
inClick = false;
}
});
})
If you want a shorter version, you can listen for both on one handler and click "the other":
var inClick = false;
$(document).ready(function {
var $sliders = $('.slider-1-prev,.slider-2-prev');
$sliders.on('click', function {
if (!inClick) {
inClick = true;
// Click the one that was not clicked (not this)
$sliders.not(this).trigger('click');
inClick = false;
}
});
})
Another option is a bit more complicated as you need to turn the handler off and then on again. Stick with this simple one for now.
The on/off approach involves disabling the handling while executing it, so that it will not trigger again until you reconnect it. The downside is you need to reference a separate function so that it can effectively reference itself:
$(document).ready(function {
var $sliders = $('.slider-1-prev,.slider-2-prev');
// Define separate named function
var clickTheOtherOne = function(){
// Disable the click
$sliders.off('click');
// Click the one that was not clicked (not this)
$sliders.not(this).trigger('click');
// Reenable the click handler
$sliders.on('click', clickTheOtherOne);
}
// Initial enabling of the handler
$sliders.on('click', clickTheOtherOne);
});

If they're going to behave the same, why not define only one function for both?
$('.slider-1-prev, .slider-2-prev').click(function(){
//... mutual code
});

I can't figure why you need to do what you ask, but try this approach:
js code:
// this will work on all classes that start with 'slider-prev'
$('*[class^="slider-prev"]').on('click',function{
// do something
});
Of course you will need to alter your htm code to:
prev
prev

this should do the trick
$(document).ready(function{
$('.slider-1-prev').on('click',function{
$('.slider-2-prev').trigger('click');
});
$('.slider-2-prev').on('click',function{
$('.slider-1-prev').trigger('click');
});
})

Try this -
$('.slider-1-prev').click(function(){
$('.slider-2-prev').trigger('click');
});
// If you need the opposite, then do -
$('.slider-2-prev').click(function(){
$('.slider-1-prev').trigger('click');
});

How to get the current active element in chrome?

I am trying to use a if statement to determine which button/textbox is submitted.
For example In firefox/IE/Opera, the following code can always return true when I click the button labeled submitNameSearch as id;
$(document.activeElement)[0] === $("#submitNameSearch")[0]
However, when I test my code in chrome/safari, the return value is false.
May I ask if I did anything wrong?
Thanks a lot for your help!

If it's triggered on a click, why don't you just do:
$('button').on('click', function() {
if (this.id=='submitNameSearch') {
//do something
}
});
and to see what element had focus before the focus was shifted to the clicked button you can always do :
var activeElm = null;
$('button').on({
mousedown: function() {
activeElm = document.activeElement;
},
click: function() {
if (activeElm&&aciveElm.id=='submitNameSearch') {
activeElm.focus; //returns focus
}
}
});

A smart toggle class in jQuery

I am trying to implement a script to set different class name on a specific element…
Let's suppose the dom looks like this:
<body class='pre-existing-class-name'>
If I make
smartToogle('body', 'new-class');
// the dom should look like this
// <body class='pre-existing-class-name new-class'>
smartToogle('body', 'new-class-2');
// the dom should look like this
// <body class='pre-existing-class-name new-class-2'>
I did the following code but it does not work:
var smartToogle = function (element, newClassName) {
var oldClassName;
var $element = $(element);
$element.addClass(newClassName);
if (oldClassName !== newClassName) {
$element.removeClass(oldClassName);
}
oldClassName = newClassName;
};
Requirements:
1) I am using query
2) I would like to pass just one class name, the new one.
Solution:
The following code works but I do not like it because it uses global variable.
Any hint to fix it?
function myToggle(newClassName) {
if (window.oldClassName) {
$('body').toggleClass(window.oldClassName);
}
window.oldClassName = newClassName;
$('body').toggleClass(newClassName);
}

You can use data attribute for the element, that is accessible using
$(element).data(attrib_name)
Just a small change is required in your method
function myToggle(newClassName) {
if (window.oldClassName) {
$('body').toggleClass(window.oldClassName);
}
window.oldClassName = newClassName;
$('body').toggleClass(newClassName);
}
can be replaced with
function myToggle(element, newClassName) {
if ($(element).data('oldClassName')) {
$(element).toggleClass($(element).data('oldClassName'));
}
$(element).data('oldClassName', newClassName)
$(element).toggleClass(newClassName);
}
Hope this solves it for you.

Update:
There is one thing you need to understand.
If you want two different behaviors you don't need 2 different classes for the change in behavior.
One is enough, because you can change the behavior based on weither the class is on or off.
Let's say I want my element to have a red hover event in one way.
And want it to have a blue hover event the other way with CSS.
Then this is the way to go:
$('#toggle').click(function(){
$('.normal').each(function(){
$(this).toggleClass('active');
});
});
JSFiddle Demo
Here we use a button to toggle all the divs and change their CSS behavior, looks easy now right?
However if you need to toggle Javascript/jQuery events as well this won't do. In that case you will need to use 3 other methods to manage this; .on(), .off(), and .hasClass().
$('#toggle').click(function(){
$('.normal').each(function(){
if($(this).hasClass('active')){
$(this).off('click');
} else {
$(this).on('click', function(){
alert('You are clicking on an active div.');
});
}
$(this).toggleClass('active');
});
});
JSFiddle Demo 2
As you can see we have added an if statement. If the element has the .active class we turn .off() the .click(). And if there isn't an active class we turn the .click() .on(). Under the if statement we always toggle the .active class. So this doesn't have to be placed inside the if statement.
I hope this clears everything up for you, good luck!
Old Answer:
It is better to use .toggleClass() here.
Use a first class on the element for the default properties and a second like .active for example for the interaction.
Also, using a .on('click', function(){}) bind will make you able to add interaction that will be bound instantly once the element is toggled.

Here's a fiddle: http://jsfiddle.net/NCwmF/2/
I little jQuery plugin for that. Removes the current smart class (if any) and adds the new smart class. If called without parameter className the current smart class gets only removed.
$.fn.smartToggle = function (className) {
var dataId = 'smartToggle';
return this.each(function () {
var $el = $(this);
$el
.removeClass($el.data(dataId) || '')
.addClass(className)
.data(dataId, className);
});
};
​use it like every other jQuery method:
$('body').smartToggle('myClass');

NEW, SIMPLER ANSWER
Works similar to before, with 2 additions: 1.) works if there is no class initially and 2.) works if other functions change the elements class in between calls. I also changed the function name so it doesn't interfere with jQuerys native toggleClass.
$.fn.fancyToggleClass = function(new_class) {
return this.each(function() {
// get the last class this function added (if exists) or false (if not)
var $this = $(this),
toggled_class = $this.data('toggled-class') || false;
// if we dont have an original class, then set it based on current class
if (toggled_class) {
$this.removeClass(toggled_class);
}
// add new class and store as data,
// which we check for next time function is called
$this.addClass(new_class).data('toggled-class', new_class);
// alert the class, just as a check to make sure everything worked!
// remove this for production, or switch to console.log
alert('element class: ' + $this.attr('class'));
});
}
updated fiddle: http://jsfiddle.net/facultymatt/xSvFC/3/
OLD ANSWER
I would suggest storing the original class in the elements data attribute. Then, your function can check if this data is set, and if so clear the elements class adding the original class from the elements data and also the new class you passed in the function.
If data is not set, the function will store the current class as data the first time it runs.
Check out this fiddle for a working example with comments: http://jsfiddle.net/facultymatt/xSvFC/
here is the code. It's a jquery function so it can be called on any element (and is chainable too!)
$.fn.toggleClass = function(new_class) {
return this.each(function() {
// cache selector for this
$this = $(this);
// get original class (if exists) or false (if not)
var original_class = $this.data('original-class') || false;
// if we dont have an original class, then set it based on current class
if (!original_class) {
original_class = $this.attr('class');
$this.data('original-class', original_class);
// we do have an original class, so we know user is now trying to add class
// here we clear the class, add the original class, and add the new class
} else {
// assign the original class, and new class,
// and a space to keep the classes from becoming one
$this.attr('class', original_class + ' ' + new_class);
}
// alert the class, just as a check to make sure everything worked!
// remove this for production, or switch to console.log
alert('element class: ' + $this.attr('class'));
});
}
Hope this helps!

To avoid a global variable you can use data attribute as #ankur writes. Here is a working solution for your problem:
function myToggle(element, newClassName) {
if (!$(element).data('baseclassname')) {
$(element).data('baseclassname', $(element).attr('class'));
}
$(element)
.attr('class', $(element).data('baseclassname'))
.addClass(newClassName);
}

Does this do your job?
var smartToogle = function (element, preExistingClassName, newClassName) {
$(element)[0].className = preExistingClassName + ' ' + newClassName;
};

Just use hasClass. But you'll have to tell the function what both classes are:
function smartToggle(element, class1, class2) {
var $element = $(element);
if ($element.hasClass(class1)) {
$element.removeClass(class1);
$element.addClass(class2);
}
else {
$element.removeClass(class2);
$element.addClass(class1);
}
}

$(function(){
var smartToggle = function (element, newClassName) {
var elementClasses = element.attr('class');
element.addClass(newClassName);
// check if there is more than one class on the element
if(elementClasses .indexOf(' ') >= 0){
var oldClassNames = elementClasses.split(" ");
if (oldClassNames[oldClassNames.length - 1] !== newClassName) {
element.removeClass(oldClassNames[oldClassNames.length - 1]);
}
}
};
smartToggle($('.test'), 'newclass');
smartToggle($('.test'), 'newclass2');
});
Demo - http://jsfiddle.net/Q9A8N/ (look at the console to see what it is doing on each pass)
That should do what you want but as #T.J. Crowder said it is rather fragile and assumes that the class you want to remove is the last one on the element.

As an answer to your question, I would go with ankur's answer
As a follow-up to Sem's answer, regarding the handling of jQuery events :
you can use the on function to handle any jquery event from a parent node, based on a live filter :
function myToggle(element, newClassName) {
if ($(element).data('oldClassName')) {
$(element).toggleClass($(element).data('oldClassName'));
}
$(element).data('oldClassName', newClassName);
$(element).toggleClass(newClassName);
}
//event delegation : 'on' is called on the $('.divContainer') node, but we handle
//clicks on '.divItm' items, depending on their current class
$('.divContainer')
.on('click', '.divItm.plain', function(){ myToggle( this, 'red' ); })
.on('click', '.divItm.red', function(){ myToggle( this, 'blue' ); })
.on('click', '.divItm.blue', function(){ myToggle( this, 'plain' ); });
//initialize each item with the 'plain' class
myToggle( $('.divItm'), 'plain' );
Here is the jsFiddle.
You will note that the function called each time you click on an item depends on its "live" class, and that you don't need to manually enable/disable click handlers each time an item changes class.
You can learn more details from the documentation page.

var smartToogle = function (element, newClass) {
var $element = $(element),
currentClass = $element.data('toggle-class');
if (currentClass != newClass) $element.data('toggle-class',newClass).removeClass(currentClass || '');
$element.toggleClass(newClass);
};
or the other variant:
$.fn.smartToogle = function (newClass) {
currentClass = this.data('toggle-class');
if (currentClass != newClass) this.data('toggle-class',newClass).removeClass(currentClass || '');
this.toggleClass(newClass);
};

In this implementation you'll have to keep the a reference to this instance of fancytoggle.
var fancytoggle = function(el, oldClass){
// create a function scope so we'll have a reference to oldClass
return function(newClass) {
// toggle the old class and the new class
$(el).toggleClass(oldClass+ ' ' + newClass);
// update the new class to be the old class
oldClass = newClass;
};
};
for your example the code would look something like.
var bodytoggle = fancytoggle('body', 'pre-existing-class-name');
bodytoggle('new-class');
// 'new-class' replaces 'pre-existing-class-name'
bodytoggle('new-class-2');
// 'new-class-2' replaces 'new-class'
to see it in action refer to http://jsfiddle.net/aaf2L/6/

jQuery .load() How to prevent double loading from double clicking

I am using jQuery load() function to load some pages into container. Here is the code:
$('div.next a').live('click',function() {
$('.content').load('page/3/ #info','',function(){
//do something
});
return false;
});
Everything works just fine but the problem is when I quickly double click the div.next link, from console I see that it loads the page twice because I did a quick double click. I could even make it 3 clicks and it will load it 3 times and show in console smth like that:
GET http://site/page/3/ 200 OK 270ms
GET http://site/page/3/ 200 OK 260ms
My question is how to prevent such double clicking and not to let load the target page more then once no matter how many times it was clicked.
Thank you.

Whatever happened to good ol' JavaScript? Why are you all trying to figure it out with pure jQuery?
var hasBeenClicked = false;
$('div.next a').live('click',function() {
if(!hasBeenClicked){
hasBeenClicked = true;
$('.content').load('page/3/ #info','',function(){
//do something
//If you want it clickable AFTER it loads just uncomment the next line
//hasBeenClicked = false;
});
}
return false;
});
As a side note, never never never use .live(). Use .delegate instead like:
var hasBeenClicked = false;
$('div.next').delegate('a','click',function() {
if(!hasBeenClicked){
hasBeenClicked = true;
$('.content').load('page/3/ #info','',function(){
//do something
//If you want it clickable AFTER it loads just uncomment the next line
//hasBeenClicked = false;
});
}
return false;
});
Why? Paul Irish explains: http://paulirish.com/2010/on-jquery-live/
To answer your comment...
This could happen if you have your delegate function nested inside your AJAX call (.load(), .get(), etc). The div.next has to be on the page for this to work. If div.next isn't on the page, and this isn't nested, just do this:
$('#wrapper').delegate('div.next a','click',function() {
http://api.jquery.com/delegate/
Delegate needs the selector to be the parent of the dynamically added element. Then, the first parameter of delegate (div.next a in the last example) is the element to look for within the selected element (#wrapper). The wrapper could also be body if it's not wrapped in any element.

You could try using the jquery one method:
$("a.button").one("click", function() {
$('.content').load('page/3/ #info','',function(){
//do something
});
});

You could unbind the click event with die():
$(this).die('click').click(function() { return False; });
Or you could give the element a .clicked class once it is clicked:
$(this).addClass('clicked');
And check if that class exists when performing your logic:
$('div.next a').live('click',function() {
if (!$(this).is('.clicked')) {
$(this).addClass('clicked');
$('.content').load('page/3/ #info','',function(){
//do something
});
}
return false;
});

Store whether you're waiting for the load in a variable.
(function() {
var waitingToLoad = false;
$('div.next a').live('click',function() {
if (!waitingToLoad) {
waitingToLoad = true;
$('.content').load('page/3/ #info','',function(){
waitingToLoad = false;
//do something
});
}
return false;
});
})()