Develop Reference

How to fix jQuery Image Sequence on Scroll

I try to implement a javascript function that animate an image sequence while scrolling.
I try to create the animation with the script from this link: https://www.jqueryscript.net/animation/jQuery-Plugin-To-Create-Image-Sequence-Animation-On-Scroll-Sequencer.html
My problem is that this script is already three years old and does not work with jQuery 3.2.1. But I have to use this much newer jQuery version.
The code of the script looks like this:
/**
* jQuery-Sequencer
* https://github.com/skruf/jQuery-sequencer
*
* Created by Thomas Låver
* http://www.laaver.com
*
* Version: 2.0.0
* Requires: jQuery 1.6+
*
*/
(function($) {
$.fn.sequencer = function(options, cb) {
var self = this,
paths = [],
load = 0,
sectionHeight,
windowHeight,
currentScroll,
percentageScroll,
index;
if(options.path.substr(-1) === "/") {
options.path = options.path.substr(0, options.path.length - 1)
}
for (var i = 0; i <= options.count; i++) {
paths.push(options.path + "/" + i + "." + options.ext);
}
$("<div class='jquery-sequencer-preload'></div>").appendTo("body").css("display", "none");
$(paths).each(function() {
$("<img>").attr("src", this).load(function() {
$(this).appendTo("div.jquery-sequencer-preload");
load++;
if (load === paths.length) {
cb();
}
});
});
$(window).scroll(function() {
sectionHeight = $(self).height();
windowHeight = $(this).height();
currentScroll = $(this).scrollTop();
percentageScroll = 100 * currentScroll / (sectionHeight - windowHeight);
index = Math.round(percentageScroll / 100 * options.count);
if(index < options.count) {
$("img.sequencer").attr("src", paths[index]);
}
});
return this;
};
}(jQuery));
So I already changed the line 37 from
$("<img>").attr("src", this).load(function() {
to
$("<img>").attr("src", this).on("load", function() {
With this change all my images are loaded but I still get the error message: Uncaught TypeError: cb is not a function
What do I have to change as well, so the script is working again?
Thanks for any tip.

cb() is a Callback function will be called once the preloader is done fetching images.
From the example you have linked to, the callback is:
function() {
$("div#preload").hide();
}
which quite simply hides the preloader message.
In context, the plugin is initialised as:
$("div#images").sequencer({
count: 128,
path: "./images",
ext: "jpg"
}, function() {
$("div#preload").hide();
});
As you have not supplied how you are calling this function, I suspect you are missing this function callback.

Using animate.css (link in description) how do I trigger an animation when a particular event is finished

I have an an image moving across the screen and out of viewport, when the image reaches a particular absolute position (right: - 200), I want to trigger the below animation. I am relatively new to programming, not sure how to track when a particular function is done so that I can trigger the below animation.
var $startLessonButton = $('.startLessonButtonUp');
$startLessonButton.mouseup(function() {
$(this).addClass('animated slideInLeft');
});
---------
var movingOutAnimationCounter = 2;
var movingOutCurrentPosition = window.innerWidth / 2 - 200
function moveTrumpOut() {
movingOutCurrentPosition -= 2;
trumpyWrapper.style.right = movingOutCurrentPosition + 'px';
if (movingOutAnimationCounter < 9 ) {
trumpy.src = '../images/trump_walking_out_' + movingOutAnimationCounter + '.png';
movingOutAnimationCounter += 1;
} else {
movingOutAnimationCounter = 1;
trumpy.src = '../images/trump_walking_out_' + movingOutAnimationCounter + '.png';
}
if (movingOutCurrentPosition > -200 ) {
requestAnimationFrame(moveTrumpOut);
}
}
All the best!

If you know time, when moving element is hidden, you can use this function:
setTimeout(function(){ $('.elem').addClass("animCssClass") }, 1000);
Last parameter, in this example: 1000 is time in ms, when function inside should execute. Run this function on mouseup when you adding class to moving element.

Is there an universal solution for looping through and animating series of .png frames with jQuery / JavaScript?

I want to display a few animated "illustrations" on a website I'm working on.
.gif is not an option due to significant loss of quality.
Is there any solution out there that would allow me to iterate through a folder of PNG's and display them on screen?
Thanks in advance.

something like this will work if the images are named 1.png through 25.png for example.
var slides = 25; //number of slides
var i = 1; //first slide
var delay = 200; //set delay
var timer;
function pngani() {
if (i <= slides) {
$('#show img').attr('src', 'pathtofile/' + i + '.png');
}
i++;
}
$('#start').click(function () {
timer = setInterval(pngani, delay);
pngani();
});
$('#pause').click(function () {
clearInterval(timer);
timer = null;
});
$('#reset').click(function () {
i = 1;
$('#show img').attr('src', 'pathtofile/' + i + '.png');
});
I added a start, pause, and reset button, so the execution can be controlled.
made a fiddle: http://jsfiddle.net/filever10/Kur9u/

Make a jQuery slider work with divs instead of images

I am working on this website page poochclub.com and I am trying to make all of it text instead of images. The problem is when I want to work on the panels below with all the information the js file (called about.js) is set to work with images instead on divs where I could potentially add text.
I am not very good at writing javascript and I need help to fix the original file which looks as follows:
<script type="text/javascript>
(function ($) {
var pages, panels, arrows, currentClass = 'current',
currentIndex = 0, currentSize = 0;
function showPage() {
var ctx = jQuery.trim(this.className.replace(/current/gi, ''));
$(this).addClass(currentClass).siblings().removeClass(currentClass);
$('.panel')
.removeClass(currentClass)
.find('img')
.removeClass(currentClass)
.removeAttr('style')
.end();
panels.find('.' + ctx)
.addClass(currentClass)
.find('img')
.removeClass(currentClass)
.removeAttr('style')
.eq(0)
.fadeIn()
.addClass(currentClass)
.end()
currentIndex = 0;
currentSize = panels.find('.' + ctx + ' img').length;
return false;
}
function showArrows(e) {
arrows['fade' + (e.type === 'mouseenter' ? 'In' : 'Out')]();
}
function getPrev() {
currentIndex = currentIndex - 1 < 0 ? currentSize - 1 : currentIndex - 1;
return currentIndex;
}
function doPrev() {
var ctx = panels.find('div.current img');
ctx.removeClass(currentClass).removeAttr('style');
ctx.eq(getPrev()).fadeIn().addClass(currentClass);
}
function getNext() {
currentIndex = currentIndex + 1 >= currentSize ? 0 : currentIndex + 1;
return currentIndex;
}
function doNext() {
var ctx = panels.find('div.current img');
ctx.removeClass(currentClass).removeAttr('style');
ctx.eq(getNext()).fadeIn().addClass(currentClass);
}
$(document).ready(function () {
pages = $('.panels-nav a');
panels = $('.panels');
arrows = $('.arrows');
pages.click(showPage);
panels.bind('mouseenter mouseleave', showArrows);
arrows.find('.prev').click(doPrev).end().find('.next').click(doNext);
pages.eq(0).click();
});
});
</script>
My questions is, how do I change the js file from finding img to finding several different div id's attached to the sliding panles?
Thanks.

any reference to img should be a new selector. Something like 'div.slider', a div with a class slider.
Look at all the finds, thats where you will see the img selectors.

javascript 'over-clicking' bug

I have a bug in Javascript where I am animating the margin left property of a parent container to show its child divs in a sort of next/previous fashion. Problem is if clicking 'next' at a high frequency the if statement seems to be ignored (i.e. only works if click, wait for animation, then click again) :
if (marLeft === (-combinedWidth + (regWidth) + "px")) {
//roll margin back to 0
}
An example can be seen on jsFiddle - http://jsfiddle.net/ZQg5V/
Any help would be appreciated.

Try the below code which will basically check if the container is being animated just return from the function.
Working demo
$next.click(function (e) {
e.preventDefault();
if($contain.is(":animated")){
return;
}
var marLeft = $contain.css('margin-left'),
$this = $(this);
if (marLeft === (-combinedWidth + (regWidth) + "px")) {
$contain.animate({
marginLeft: 0
}, function () {
$back.fadeOut('fast');
});
} else {
$back.fadeIn(function () {
$contain.animate({
marginLeft: "-=" + regWidth + "px"
});
});
}
if (marLeft > -combinedWidth) {
$contain.animate({
marginLeft: 0
});
}
});

Sometimes is better if you create a function to take care of the animation, instead of writting animation code on every event handler (next, back). Also, users won't have to wait for the animation to finish in order to go the nth page/box.
Maybe this will help you:
if (jQuery) {
var $next = $(".next"),
$back = $(".back"),
$box = $(".box"),
regWidth = $box.width(),
$contain = $(".wrap")
len = $box.length;
var combinedWidth = regWidth*len;
$contain.width(combinedWidth);
var currentBox = 0; // Keeps track of current box
var goTo = function(n) {
$contain.animate({
marginLeft: -n*regWidth
}, {
queue: false, // We don't want animations to queue
duration: 600
});
if (n == 0) $back.fadeOut('fast');
else $back.fadeIn('fast');
currentBox = n;
};
$next.click(function(e) {
e.preventDefault();
var go = currentBox + 1;
if (go >= len) go = 0; // Index based, instead of margin based...
goTo(go);
});
$back.click(function(e) {
e.preventDefault();
var go = currentBox - 1;
if (go <= 0) go = 0; //In case back is pressed while fading...
goTo(go);
});
}
Here's an updated version of your jsFiddle: http://jsfiddle.net/victmo/ZQg5V/5/
Cheers!

Use a variable to track if the animation is taking place. Pseudocode:
var animating = false;
function myAnimation() {
if (animating) return;
animating = true;
$(this).animate({what:'ever'}, function() {
animating = false;
});
}
Crude, but it should give you the idea.
Edit: Your current code works fine for me as well, even if I jam out on the button. On firefox.