jQuery $.post causes browser stack overflow - javascript

I have the following jQuery code:
var id_atual
var temp_id
var tempo_flash = 50
var $slide_atual = $('#slider .atual')
var $slide_prox = $('#slider .ocultar')
setInterval(function(){
id_atual = $slide_atual.attr('alt')
$.post('get_banner.php', {atual: id_atual}, function(proximo){
temp_id = proximo.split(';;')
$slide_prox.attr('src', temp_id[0]).load(function(){
$slide_atual.hide('fade', tempo_flash, function(){
$slide_atual.attr('alt', temp_id[1]).attr('src', temp_id[0]).load(function(){
$slide_atual.show('fade', tempo_flash)
})
})
})
})
}, 4000)
And the following HTML code:
<div id="slider">
<img src="imagens/slider/imagen-slider.jpg" alt="1" class="atual"/>
<img src="" alt="" class="ocultar" />
</div>
Where the class .ocultar have a
display: none;
The vars tempo_flash is only the animation time, and the file get_banner.php is only for getting the next banner from the mysql database. It is tested and working fine.
The problem I have is that after a little (4 or 5 banner changing) the browser stops answering (for Firefox Chrome and Opera) and on IE I get an alert Stack overflow at line: 3 and the javascript of the whole page stops working.
Any help appreciated!

Inside each iteration of the setInterval()ed function, you assign a .load() event to an image place holder. Assigning an event to an object does not remove existing ones!
So on second iteration, the image place holder will have two .load() event handlers, then three and so on; and every time the image is loaded, it will fire all event handlers attached to .load() event. You probably need to re-factor your code, perhaps by assigning the .load() event handler only once (and use semicolons).

you shouldn't use setInterval, you should use a setTimeout inside a function, and execute it on the callback of the $.post, something like:
var id_atual
var temp_id
var tempo_flash = 50
var $slide_atual = $('#slider .atual')
var $slide_prox = $('#slider .ocultar')
function tictac(){
setTimeout(function(){
id_atual = $slide_atual.attr('alt')
$.post('get_banner.php', {atual: id_atual}, function(proximo){
temp_id = proximo.split(';;')
$slide_prox.attr('src', temp_id[0]).load(function(){
$slide_atual.hide('fade', tempo_flash, function(){
$slide_atual.attr('alt', temp_id[1]).attr('src', temp_id[0]).load(function(){
$slide_atual.show('fade', tempo_flash)
})
})
})
})
ticktac();
}, 4000);
}
this way, the 4 seconds only start counting if and when the response from the server is complete, you will not have your overflow problems

Related

Increase value of counter by one upon class creation/append

Creating a system that increases the 'fault' counter by a value of one upon every wrong answer submitted. I'm doing this by having my system listen out for the creation of a class called "incorrectResponse". However, it appears to just add to the counter as soon as the page finishes loading and doesn't add any more values after that.
Here is the code I've tried that isn't working.
//*-- Fault counter --*//
if (document.querySelectorAll('incorrectResponse')) {
$('#fault-counter').html(function(i, val) { return val*1+1 });
};
Any reason as to why this is the case?
Assumming you're using jQuery (you mention it in one of your comments), one thing you could do is attach an event listener to the container of your 'wrong answers'.
A custom event would be triggered manually any time a wrong answer is received/appended to the page and the event listener would react to it recalculating the number of wrong answers and updating the counter.
function updateNumberOfIncorrectMsgs() {
$('.counter').text($('.incorrectAnswer').length);
}
updateNumberOfIncorrectMsgs();
var $container = $('.wrongAnswersContainer')
.on('newWrongAnswerAdded', function() {
updateNumberOfIncorrectMsgs();
});
// The for and setTimeout is only to simulate msgs appended to the page, the important part is the custom event that gets triggered when an element is added.
for (var i = 1; i < 6; i++) {
setTimeout(function() {
$container
.append('<p class="incorrectAnswer">Incorrect answer</p>')
.trigger('newWrongAnswerAdded');
}, 1000 * i);
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p>Incorrect answer counter: <span class="counter"></span>
</p>
<div class="wrongAnswersContainer"></div>

How to add load event of dynamically added elements [duplicate]

How do you add an onload event to an element?
Can I use:
<div onload="oQuickReply.swap();" ></div>
for this?
No, you can't. The easiest way to make it work would be to put the function call directly after the element
Example:
...
<div id="somid">Some content</div>
<script type="text/javascript">
oQuickReply.swap('somid');
</script>
...
or - even better - just in front of </body>:
...
<script type="text/javascript">
oQuickReply.swap('somid');
</script>
</body>
...so it doesn't block the following content from loading.
You can trigger some js automatically on an IMG element using onerror, and no src.
<img src onerror='alert()'>
The onload event can only be used on the document(body) itself, frames, images, and scripts. In other words, it can be attached to only body and/or each external resource. The div is not an external resource and it's loaded as part of the body, so the onload event doesn't apply there.
onload event it only supports with few tags like listed below.
<body>, <frame>, <iframe>, <img>, <input type="image">, <link>, <script>, <style>
Here the reference for onload event
Try this! And never use trigger twice on div!
You can define function to call before the div tag.
$(function(){
$('div[onload]').trigger('onload');
});
DEMO: jsfiddle
I just want to add here that if any one want to call a function on load event of div & you don't want to use jQuery(due to conflict as in my case) then simply call a function after all the html code or any other code you have written including the function code and
simply call a function .
/* All Other Code*/
-----
------
/* ----At the end ---- */
<script type="text/javascript">
function_name();
</script>
OR
/* All Other Code*/
-----
------
/* ----At the end ---- */
<script type="text/javascript">
function my_func(){
function definition;
}
my_func();
</script>
I needed to have some initialization code run after a chunk of html (template instance) was inserted, and of course I didn't have access to the code that manipulates the template and modifies the DOM. The same idea holds for any partial modification of the DOM by insertion of an html element, usually a <div>.
Some time ago, I did a hack with the onload event of a nearly invisible <img> contained in a <div>, but discovered that a scoped, empty style will also do:
<div .... >
<style scoped="scoped" onload="dosomethingto(this.parentElement);" > </style>
.....
</div>
Update(Jul 15 2017) -
The <style> onload is not supported in last version of IE. Edge does support it, but some users see this as a different browser and stick with IE. The <img> element seems to work better across all browsers.
<div...>
<img onLoad="dosomthing(this.parentElement);" src="data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" />
...
</div>
To minimize the visual impact and resource usage of the image, use an inline src that keeps it small and transparent.
One comment I feel I need to make about using a <script>is how much harder it is to determine which <div> the script is near, especially in templating where you can't have an identical id in each instance that the template generates. I thought the answer might be document.currentScript, but this is not universally supported. A <script> element cannot determine its own DOM location reliably; a reference to 'this' points to the main window, and is of no help.
I believe it is necessary to settle for using an <img> element, despite being goofy. This might be a hole in the DOM/javascript framework that could use plugging.
Avoid using any interval-based methods (as they are not performant and accurate) and use MutationObserver targeting a parent div of dynamically loaded div for better efficiency.
Update: Here's a handy function I wrote. Use it like this:
onElementLoaded("div.some_class").then(()=>{}).catch(()=>{});
/**
*
* Wait for an HTML element to be loaded like `div`, `span`, `img`, etc.
* ex: `onElementLoaded("div.some_class").then(()=>{}).catch(()=>{})`
* #param {*} elementToObserve wait for this element to load
* #param {*} parentStaticElement (optional) if parent element is not passed then `document` is used
* #return {*} Promise - return promise when `elementToObserve` is loaded
*/
function onElementLoaded(elementToObserve, parentStaticElement) {
const promise = new Promise((resolve, reject) => {
try {
if (document.querySelector(elementToObserve)) {
console.log(`element already present: ${elementToObserve}`);
resolve(true);
return;
}
const parentElement = parentStaticElement
? document.querySelector(parentStaticElement)
: document;
const observer = new MutationObserver((mutationList, obsrvr) => {
const divToCheck = document.querySelector(elementToObserve);
if (divToCheck) {
console.log(`element loaded: ${elementToObserve}`);
obsrvr.disconnect(); // stop observing
resolve(true);
}
});
// start observing for dynamic div
observer.observe(parentElement, {
childList: true,
subtree: true,
});
} catch (e) {
console.log(e);
reject(Error("some issue... promise rejected"));
}
});
return promise;
}
Implementation details:
HTML:
<div class="parent-static-div">
<div class="dynamic-loaded-div">
this div is loaded after DOM ready event
</div>
</div>
JS:
var observer = new MutationObserver(function (mutationList, obsrvr) {
var div_to_check = document.querySelector(".dynamic-loaded-div"); //get div by class
// var div_to_check = document.getElementById('div-id'); //get div by id
console.log("checking for div...");
if (div_to_check) {
console.log("div is loaded now"); // DO YOUR STUFF!
obsrvr.disconnect(); // stop observing
return;
}
});
var parentElement = document.querySelector("parent-static-div"); // use parent div which is already present in DOM to maximise efficiency
// var parentElement = document // if not sure about parent div then just use whole 'document'
// start observing for dynamic div
observer.observe(parentElement, {
// for properties details: https://developer.mozilla.org/en-US/docs/Web/API/MutationObserverInit
childList: true,
subtree: true,
});
we can use MutationObserver to solve the problem in efficient way adding a sample code below
<!DOCTYPE html>
<html>
<head>
<title></title>
<style>
#second{
position: absolute;
width: 100px;
height: 100px;
background-color: #a1a1a1;
}
</style>
</head>
<body>
<div id="first"></div>
<script>
var callthis = function(element){
element.setAttribute("tabIndex",0);
element.focus();
element.onkeydown = handler;
function handler(){
alert("called")
}
}
var observer = new WebKitMutationObserver(function(mutations) {
mutations.forEach(function(mutation) {
for (var i = 0; i < mutation.addedNodes.length; i++)
if(mutation.addedNodes[i].id === "second"){
callthis(mutation.addedNodes[i]);
}
})
});
observer.observe(document.getElementById("first"), { childList: true });
var ele = document.createElement('div');
ele.id = "second"
document.getElementById("first").appendChild(ele);
</script>
</body>
</html>
In November 2019, I am seeking a way to create a (hypothetical) onparse EventListener for <elements> which don't take onload.
The (hypothetical) onparse EventListener must be able to listen for when an element is parsed.
Third Attempt (and Definitive Solution)
I was pretty happy with the Second Attempt below, but it just struck me that I can make the code shorter and simpler, by creating a tailor-made event:
let parseEvent = new Event('parse');
This is the best solution yet.
The example below:
Creates a tailor-made parse Event
Declares a function (which can be run at window.onload or any time) which:
Finds any elements in the document which include the attribute data-onparse
Attaches the parse EventListener to each of those elements
Dispatches the parse Event to each of those elements to execute the Callback
Working Example:
// Create (homemade) parse event
let parseEvent = new Event('parse');
// Create Initialising Function which can be run at any time
const initialiseParseableElements = () => {
// Get all the elements which need to respond to an onparse event
let elementsWithParseEventListener = document.querySelectorAll('[data-onparse]');
// Attach Event Listeners and Dispatch Events
elementsWithParseEventListener.forEach((elementWithParseEventListener) => {
elementWithParseEventListener.addEventListener('parse', updateParseEventTarget, false);
elementWithParseEventListener.dataset.onparsed = elementWithParseEventListener.dataset.onparse;
elementWithParseEventListener.removeAttribute('data-onparse');
elementWithParseEventListener.dispatchEvent(parseEvent);
});
}
// Callback function for the Parse Event Listener
const updateParseEventTarget = (e) => {
switch (e.target.dataset.onparsed) {
case ('update-1') : e.target.textContent = 'My First Updated Heading'; break;
case ('update-2') : e.target.textContent = 'My Second Updated Heading'; break;
case ('update-3') : e.target.textContent = 'My Third Updated Heading'; break;
case ('run-oQuickReply.swap()') : e.target.innerHTML = 'This <code><div></code> is now loaded and the function <code>oQuickReply.swap()</code> will run...'; break;
}
}
// Run Initialising Function
initialiseParseableElements();
let dynamicHeading = document.createElement('h3');
dynamicHeading.textContent = 'Heading Text';
dynamicHeading.dataset.onparse = 'update-3';
setTimeout(() => {
// Add new element to page after time delay
document.body.appendChild(dynamicHeading);
// Re-run Initialising Function
initialiseParseableElements();
}, 3000);
div {
width: 300px;
height: 40px;
padding: 12px;
border: 1px solid rgb(191, 191, 191);
}
h3 {
position: absolute;
top: 0;
right: 0;
}
<h2 data-onparse="update-1">My Heading</h2>
<h2 data-onparse="update-2">My Heading</h2>
<div data-onparse="run-oQuickReply.swap()">
This div hasn't yet loaded and nothing will happen.
</div>
Second Attempt
The First Attempt below (based on #JohnWilliams' brilliant Empty Image Hack) used a hardcoded <img /> and worked.
I thought it ought to be possible to remove the hardcoded <img /> entirely and only dynamically insert it after detecting, in an element which needed to fire an onparse event, an attribute like:
data-onparse="run-oQuickReply.swap()"
It turns out, this works very well indeed.
The example below:
Finds any elements in the document which include the attribute data-onparse
Dynamically generates an <img src /> and appends it to the document, immediately after each of those elements
Fires the onerror EventListener when the rendering engine parses each <img src />
Executes the Callback and removes that dynamically generated <img src /> from the document
Working Example:
// Get all the elements which need to respond to an onparse event
let elementsWithParseEventListener = document.querySelectorAll('[data-onparse]');
// Dynamically create and position an empty <img> after each of those elements
elementsWithParseEventListener.forEach((elementWithParseEventListener) => {
let emptyImage = document.createElement('img');
emptyImage.src = '';
elementWithParseEventListener.parentNode.insertBefore(emptyImage, elementWithParseEventListener.nextElementSibling);
});
// Get all the empty images
let parseEventTriggers = document.querySelectorAll('img[src=""]');
// Callback function for the EventListener below
const updateParseEventTarget = (e) => {
let parseEventTarget = e.target.previousElementSibling;
switch (parseEventTarget.dataset.onparse) {
case ('update-1') : parseEventTarget.textContent = 'My First Updated Heading'; break;
case ('update-2') : parseEventTarget.textContent = 'My Second Updated Heading'; break;
case ('run-oQuickReply.swap()') : parseEventTarget.innerHTML = 'This <code><div></code> is now loaded and the function <code>oQuickReply.swap()</code> will run...'; break;
}
// Remove empty image
e.target.remove();
}
// Add onerror EventListener to all the empty images
parseEventTriggers.forEach((parseEventTrigger) => {
parseEventTrigger.addEventListener('error', updateParseEventTarget, false);
});
div {
width: 300px;
height: 40px;
padding: 12px;
border: 1px solid rgb(191, 191, 191);
}
<h2 data-onparse="update-1">My Heading</h2>
<h2 data-onparse="update-2">My Heading</h2>
<div data-onparse="run-oQuickReply.swap()">
This div hasn't yet loaded and nothing will happen.
</div>
First Attempt
I can build on #JohnWilliams' <img src> hack (on this page, from 2017) - which is, so far, the best approach I have come across.
The example below:
Fires the onerror EventListener when the rendering engine parses <img src />
Executes the Callback and removes the <img src /> from the document
Working Example:
let myHeadingLoadEventTrigger = document.getElementById('my-heading-load-event-trigger');
const updateHeading = (e) => {
let myHeading = e.target.previousElementSibling;
if (true) { // <= CONDITION HERE
myHeading.textContent = 'My Updated Heading';
}
// Modern alternative to document.body.removeChild(e.target);
e.target.remove();
}
myHeadingLoadEventTrigger.addEventListener('error', updateHeading, false);
<h2>My Heading</h2>
<img id="my-heading-load-event-trigger" src />
use an iframe and hide it iframe works like a body tag
<!DOCTYPE html>
<html>
<body>
<iframe style="display:none" onload="myFunction()" src="http://www.w3schools.com"></iframe>
<p id="demo"></p>
<script>
function myFunction() {
document.getElementById("demo").innerHTML = "Iframe is loaded.";
}
</script>
</body>
</html>
Since the onload event is only supported on a few elements, you have to use an alternate method.
You can use a MutationObserver for this:
const trackElement = element => {
let present = false;
const checkIfPresent = () => {
if (document.body.contains(element)) {
if (!present) {
console.log('in DOM:', element);
}
present = true;
} else if (present) {
present = false;
console.log('Not in DOM');
}
};
const observer = new MutationObserver(checkIfPresent);
observer.observe(document.body, { childList: true });
checkIfPresent();
return observer;
};
const element = document.querySelector('#element');
const add = () => document.body.appendChild(element);
const remove = () => element.remove();
trackElement(element);
<button onclick="add()">Add</button>
<button onclick="remove()">Remove</button>
<div id="element">Element</div>
we can use all these tags with onload
<body>, <frame>, <frameset>, <iframe>, <img>, <input type="image">, <link>, <script> and <style>
eg:
function loadImage() {
alert("Image is loaded");
}
<img src="https://www.w3schools.com/tags/w3html.gif" onload="loadImage()" width="100" height="132">
I really like the YUI3 library for this sort of thing.
<div id="mydiv"> ... </div>
<script>
YUI().use('node-base', function(Y) {
Y.on("available", someFunction, '#mydiv')
})
See: http://developer.yahoo.com/yui/3/event/#onavailable
This is very simple solution and 100% working.
Just load an <img> tag inside the div or at last line of div, if you think you want to execute javascript, after loading all data in div.
As <img> tag supports onload event, so you can easily call javascript here like below:
<div>
<img onLoad="alert('Problem Solved');" src="data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" />
</div>
This above image will show only a single Dot(.), which you even cant see normally.
Try it.
First to answer your question: No, you can't, not directly like you wanted to do so.
May be a bit late to answer, but this is my solution, without jQuery, pure javascript.
It was originally written to apply a resize function to textareas after DOM is loaded and on keyup.
Same way you could use it to do something with (all) divs or only one, if specified, like so:
document.addEventListener("DOMContentLoaded", function() {
var divs = document.querySelectorAll('div'); // all divs
var mydiv = document.getElementById('myDiv'); // only div#myDiv
divs.forEach( div => {
do_something_with_all_divs(div);
});
do_something_with_mydiv(mydiv);
});
If you really need to do something with a div, loaded after the DOM is loaded, e.g. after an ajax call, you could use a very helpful hack, which is easy to understand an you'll find it ...working-with-elements-before-the-dom-is-ready.... It says "before the DOM is ready" but it works brillant the same way, after an ajax insertion or js-appendChild-whatever of a div. Here's the code, with some tiny changes to my needs.
css
.loaded { // I use only class loaded instead of a nodename
animation-name: nodeReady;
animation-duration: 0.001s;
}
#keyframes nodeReady {
from { clip: rect(1px, auto, auto, auto); }
to { clip: rect(0px, auto, auto, auto); }
}
javascript
document.addEventListener("animationstart", function(event) {
var e = event || window.event;
if (e.animationName == "nodeReady") {
e.target.classList.remove('loaded');
do_something_else();
}
}, false);
I am learning javascript and jquery and was going through all the answer,
i faced same issue when calling javascript function for loading div element.
I tried $('<divid>').ready(function(){alert('test'}) and it worked for me. I want to know is this good way to perform onload call on div element in the way i did using jquery selector.
thanks
As all said, you cannot use onLoad event on a DIV instead but it before body tag.
but in case you have one footer file and include it in many pages. it's better to check first if the div you want is on that page displayed, so the code doesn't executed in the pages that doesn't contain that DIV to make it load faster and save some time for your application.
so you will need to give that DIV an ID and do:
var myElem = document.getElementById('myElementId');
if (myElem !== null){ put your code here}
I had the same question and was trying to get a Div to load a scroll script, using onload or load. The problem I found was that it would always work before the Div could open, not during or after, so it wouldn't really work.
Then I came up with this as a work around.
<body>
<span onmouseover="window.scrollTo(0, document.body.scrollHeight);"
onmouseout="window.scrollTo(0, document.body.scrollHeight);">
<div id="">
</div>
Link to open Div
</span>
</body>
I placed the Div inside a Span and gave the Span two events, a mouseover and a mouseout. Then below that Div, I placed a link to open the Div, and gave that link an event for onclick. All events the exact same, to make the page scroll down to bottom of page. Now when the button to open the Div is clicked, the page will jump down part way, and the Div will open above the button, causing the mouseover and mouseout events to help push the scroll down script. Then any movement of the mouse at that point will push the script one last time.
You could use an interval to check for it until it loads like this:
https://codepen.io/pager/pen/MBgGGM
let checkonloadDoSomething = setInterval(() => {
let onloadDoSomething = document.getElementById("onloadDoSomething");
if (onloadDoSomething) {
onloadDoSomething.innerHTML="Loaded"
clearInterval(checkonloadDoSomething);
} else {`enter code here`
console.log("Waiting for onloadDoSomething to load");
}
}, 100);
When you load some html from server and insert it into DOM tree you can use DOMSubtreeModified however it is deprecated - so you can use MutationObserver or just detect new content inside loadElement function directly so you will don't need to wait for DOM events
var ignoreFirst=0;
var observer = (new MutationObserver((m, ob)=>
{
if(ignoreFirst++>0) {
console.log('Element add on', new Date());
}
}
)).observe(content, {childList: true, subtree:true });
// simulate element loading
var tmp=1;
function loadElement(name) {
setTimeout(()=>{
console.log(`Element ${name} loaded`)
content.innerHTML += `<div>My name is ${name}</div>`;
},1500*tmp++)
};
loadElement('Michael');
loadElement('Madonna');
loadElement('Shakira');
<div id="content"><div>
You can attach an event listener as below. It will trigger whenever the div having selector #my-id loads completely to DOM.
$(document).on('EventName', '#my-id', function() {
// do something
});
Inthis case EventName may be 'load' or 'click'
https://api.jquery.com/on/#on-events-selector-data-handler
Here is a trick that worked for me,
you just need to put your div inside a body element
<body>
<!-- Some code here -->
<body onload="alert('Hello World')">
<div ></div>
</body>
<!-- other lines of code -->
</body>
Use the body.onload event instead, either via attribute (<body onload="myFn()"> ...) or by binding an event in Javascript. This is extremely common with jQuery:
$(document).ready(function() {
doSomething($('#myDiv'));
});
You cannot add event onload on div, but you can add onkeydown and trigger onkeydown event on document load
$(function ()
{
$(".ccsdvCotentPS").trigger("onkeydown");
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.2.3/jquery.min.js"></script>
<div onkeydown="setCss( );"> </div>`
Try this.
document.getElementById("div").onload = alert("This is a div.");
<div id="div">Hello World</div>
Try this one too. You need to remove . from oQuickReply.swap() to make the function working.
document.getElementById("div").onload = oQuickReplyswap();
function oQuickReplyswap() {
alert("Hello World");
}
<div id="div"></div>

Can you do a loop to change array size depending on the number of photos in a file in javascript/php?

Sorry for the question isn't very clear, basically
I have got the php code to search for photos in the directory based on the userId given in the url. So if the userId = 1, it will go to Photos/1 and get all the photos in that directory and output it into an array that I can use in Javascript. It works.
I have an external javascript to my php/html code.
I am changing the attr of the div's to display the photos. I have 5 "photo containers" in the array called photodisplay:
var photodisplay =
[
$("#photo1"),
$("#photo2"),
$("#photo3"),
$("#photo4"),
$("#photo5"),
];
Then I have a loop to change the attribute/img src:
function preloadingPhotos() {
for (var x=0; x<galleryarray.length; x++)
{
photodisplay[x].attr("src", "Photos/" + userid + "/" + galleryarray[x]);
console.log("preloaded photos");
}
displayPhoto();
}
It works. Providing no more than 5 photos because that is how many photocontainers I have. But what if I had photos? The question is: Would I be able to do a loop to keep changing the photos in the photodisplay array?
I also have code for the photocontainers to fade in and out:
function displayPhoto(){
photodisplay[0].fadeIn(3000);
photodisplay[0].delay(3000).fadeOut(3000, function() { //first callback func
photodisplay[1].fadeIn(3000);
photodisplay[1].delay(3000).fadeOut(3000, function() { //second callback func
photodisplay[2].fadeIn(3000);
photodisplay[2].delay(3000).fadeOut(3000, function() { //third callback func
photodisplay[3].fadeIn(3000);
photodisplay[3].delay(3000).fadeOut(3000, function() { // fourth callback func
photodisplay[4].fadeIn(3000);
photodisplay[4].delay(3000).fadeOut(3000, function() {
setTimeout(displayPhoto(), 3000);
});
});
});
});
});
}// end of function displayPhoto
Which requires me to manually enter the number of the array of the photodisplay.
I would thinking of adding more to the array with duplications of the photocontainers. But I don't think that would work since I would have to manually enter the number of the array in the code above to make it fade in and out.
Sorry if this is confusing. I tried my best to explain my problem. I hope someone can help. Don't worry about the retrieving images in the directory part, because it works. It increases the array of photos accordingly, I just don't know how to adjust this change with my javascript.
The method you are using, does not scale as you have a callback function for every element in your slideshow.
What you should do, is put all images in a list (or a list of div's) and hide them all / change the z-index so that only the active one shows. The you can loop through your elements using .next() on the list items to get the next one (or the first one if .next().length is 0).
This will clean up your code and is pretty easy to do yourself but there are also loads of jQuery plugins that do it for you.
You need a little bit of abstraction here. So instead of manually code numbers, try another approach. For this example I've used jQuery; since you've tagged your question with it, I assume it's okay:
// Set a default value and store the current photo in it.
var currentPhoto = 0;
// Calculate the total number of photos
var photoTotal = photodisplay.length;
var photoTimeout = false;
// Create a function to go to the next photo
var nextPhoto = function () {
// Keep track of the new current
currentPhoto = (currentPhoto + 1) % photoTotal;
// Just to be sure clearTimeout
clearTimeout(photoTimeout);
// Fadein each photo; you might want to do something to reset the style
photodisplay[0].fadeIn({
duration: 3000,
complete: function () {
photoTimeout = setTimeout(nextPhoto, 3000);
}
});
}
nextPhoto();
You don't want to define JS from the backend like that; just have PHP render the markup, then use JS to query and parse the markup for the presentational layer.
Let's assume your markup looks like this:
<div id="photocontainers">
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
</div>
<!-- A hidden array of images. -->
<div id="images">
<img src="http://placehold.it/100x100&text=1" />
<img src="http://placehold.it/100x100&text=2" />
<img src="http://placehold.it/100x100&text=3" />
<img src="http://placehold.it/100x100&text=4" />
<img src="http://placehold.it/100x100&text=5" />
<img src="http://placehold.it/100x100&text=6" />
<img src="http://placehold.it/100x100&text=7" />
<img src="http://placehold.it/100x100&text=8" />
<img src="http://placehold.it/100x100&text=9" />
<img src="http://placehold.it/100x100&text=10" />
<img src="http://placehold.it/100x100&text=11" />
</div>
So your server renders this; #images is just a hidden container, that basically preloads all the image assets you'll cycle between in #photocontainers.
var cycleImages = function() {
// Cache selectors that we'll need.
var $photoContainers = $('#photocontainers').children(),
$images = $('#images img'),
// Use `.data()` to get the starting point, or set to 0
// (if this is the first time the function ran).
startImage = $images.data('nextImage') || 0;
// Loop from the starting point, filling up the number of
// photocontainers in the DOM.
for (var i = startImage; i < startImage + $photoContainers.length; i++) {
var $targetImage = $images.eq(i % $images.length),
$targetPhotoContainer = $photoContainers.eq(i - startImage);
// Get rid of the current contents.
$targetPhotoContainer.empty();
// Clone the desired image, and append it into place.
$targetImage.clone().appendTo($targetPhotoContainer).fadeOut(0).fadeIn();
}
// Let's figure out which starting image is next up, and store that
// with `.data()`.
var nextImage = startImage + $photoContainers.length;
if (nextImage >= $images.length) {
nextImage -= $images.length;
}
$images.data('nextImage', nextImage);
}
// When the DOM is ready, call the method, then
// call it again however often you'd like.
$(document).ready(function() {
cycleImages();
setInterval(function() {
cycleImages();
}, 3000);
});
Here's a plunkr showing that in action: http://plnkr.co/SumqkXYpRXcOqEhAPOHm

Appending hash/subpage to URL when loading content in expanding divs

I'm loading in separate .html documents inside divs with this code:
JS
$('.thumbnail').click(function() {
var idStr = ("project/"+$(this).attr('id')) + " #projectcontainer";
$('#projectcontainer').animate({opacity:0});
$('#projectcontainer').hide().load(idStr,function(){
$(this).slideDown(500).animate({opacity:1}, function() {
$.scrollTo('#gohere',800);
$('#close').fadeIn(500).css({'display': 'block', 'height': '25px'});
});
});
});
HTML
<div class="thumbnail" id="atmotype.html">
<img src="image.whatever">
</div>
It all works as intended but I also wanna append an ID when you open a project, and also be able to link directly to said content (already expanded in the div). I've been trying around and can't come up with a solution, and that being said I'm pretty awful with JS in general.
Would really appreciate if someone could enlighten me on how this works.
Right now when you click your .thumbnail element, it is firing your click() event and using $(this).attr('id') for the hash/scroll. To make this run when the page load, you should probably break it out to a separate function that takes the ID as a parameter, and then call this function from your click() event as well as a generic page load using a parameter in location.hash.
$(document).ready(function(){
if (location.hash.length>0){
/* this assumes the page to load is the only thing in the
hash, for example /page.php#project.html */
var hash = location.hash.substring(1); // get hash and remove #
addHashAndScroll(hash); // call function with page name
}
$('.thumbnail').click(function() {
addHashAndScroll($(this).attr('id')); // pass ID value to function
});
}
// this function contains most of your original script
function addHashAndScroll(id){
var idStr = "project/"+ id + "#projectcontainer";
// rest of your code
}
UPDATE:
This is the thing about js it all makes sense when explained but executing it is a bitch. Anyways thanks alot for helping out. Based on your explanation what I get is:
$(document).ready(function() {
if (location.hash.length > 0) {
/* this assumes the page to load is the only thing in the
hash, for example /page.php#project.html */
var hash = location.hash.substring(1); // get hash and remove #
addHashAndScroll(hash); // call function with page name
}
$('.thumbnail').click(function() {
addHashAndScroll($(this).attr('id')); // pass ID value to function
});
}
// this function contains most of your original script
function addHashAndScroll(id) {
var idStr = "project/" + id + "#projectcontainer";
$('#projectcontainer').animate({
opacity: 0
});
$('#projectcontainer').hide().load(idStr, function() {
$(this).slideDown(500).animate({
opacity: 1
}, function() {
$.scrollTo('#gohere', 800);
$('#close').fadeIn(500).css({
'display': 'block',
'height': '25px'
});
});
});
}
I've tried to fiddle around with the closures and whatever minimal experience i have in bug testing js but i keep getting errors originating from this line:
function addHashAndScroll(id) {

Highlight image borders with Ajax request

First, some visualization of the code.
I have the following images that are dynamically generated from jquery. They're made upon user request:
<img id="i13133" src="someimage.jpg" />
<img id="i13232" src="someimage1.jpg" />
<img id="i14432" src="someimage2.jpg" />
<img id="i16432" src="someimage3.jpg" />
<img id="i18422" src="someimage4.jpg" />
I have an AJAX loop that repeats every 15 seconds using jQuery and it contains the following code:
Note: The if statement is inside the Ajax loop.
Where imgId is the requested ID from the Ajax call.
//Passes the IDs retrieved from Ajax, if the IDs exist on the page the animation is triggered.
if ( $('#i' + imgId ).length )
{
var pickimage = '#i' + imgId;
var stop = false;
function highlight(pickimage) {
$(pickimage).animate({color: "yellow"}, 1000, function () {
$(pickimage ).animate({color: "black"}, 1000, function () {
if (!stop) highlight(pickimage);
});
});
}
// Start the loop
highlight(pickimage);
}
It works great, even with multiple images. But I had originally used this with one image.
The problem is I need an interrupt. Something like:
$(img).click(function () {
stop = true;
});
There's two problems:
1.)This obviously stops all animations. I can't wrap my head around how I could write something that only stops the animation of the image that's clicked.
2.)The Ajax retrieves IDs, sometimes those IDs appear more than once every few minutes, which means it would repeat the animations on top of each other if the image exists. I could use some help figuring out how to detect if an animation is already running on an image, and do nothing if the animation is already triggered on an image.
You can hit two birds with one stone ;)
1) Don't use the stop variable. Add a class to each img:
// Instead of: var stop = false;
$(pickimage).addClass("animating");
// Instead of: if (!stop) highlight(pickimage);
if ($(pickimage).hasClass("animating")) highlight(pickimage);
// Instead of: $(img).click(function () { stop = true; });
$(img).click(function () { $(this).removeClass("animating"); });
2) Same thing, check the class!
if ($(pickimage).hasClass("animating")) return;

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