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Jscroll pagination plugin

i have download this good plugin
http://andersonferminiano.com/jqueryscrollpagination/
and i use this code for do a call to my db and show all the result. The my problem is that i can't stop the showing results when are finish in the database, i wouold like stop the pagination and no repeat the same result. how can i do it? thank you so much
$(function(){
$('#content').scrollPagination({
'contentPage': 'democontent.html', // the page where you are searching for results
'contentData': {}, // you can pass the children().size() to know where is the pagination
'scrollTarget': $(window), // who gonna scroll? in this example, the full window
'heightOffset': 10, // how many pixels before reaching end of the page would loading start? positives numbers only please
'beforeLoad': function(){ // before load, some function, maybe display a preloader div
$('.loading').fadeIn();
},
'afterLoad': function(elementsLoaded){ // after loading, some function to animate results and hide a preloader div
$('.loading').fadeOut();
var i = 0;
$(elementsLoaded).fadeInWithDelay();
if ($('#content').children().size() > 100){ // if more than 100 results loaded stop pagination (only for test)
$('#content').stopScrollPagination();
}
}
});
// code for fade in element by element with delay
$.fn.fadeInWithDelay = function(){
var delay = 0;
return this.each(function(){
$(this).delay(delay).animate({opacity:1}, 200);
delay += 100;
});
};
});

That plugin actually isn't very good. I'm looking at the plugin's code, and sure enough, it doesn't provide a way to detect when you're at the end of the content.
If you go to the plugin page and scroll down, it appears to be working quite nicely. However, when you look at the file democontent.html (he's hidden the text, you have to view the source) where the data is being retrieved from, you'll see it's only 17 items. But, it keeps loading bogus data as you scroll down.
Not only does the plugin not detect the end of the data, but it also doesn't provide a way of stopping at all. If you'll notice, Anderson told the plugin to stop after 100 items are loaded, but he did this only in his example instead of writing this feature into the plugin.
So, that's why your content isn't stopping. You could try modifying his plugin yourself, but if you'd rather just change plugins, I'd recommend Infinite Scroll, by Paul Irish.

You can use mkscroll plugin with is provide you more functionality link for mk scroll is below.
https://github.com/maulikkanani/Scroll-Pagination
jQuery(window).mkscroll({
limit:10,
total:100,
});
there are many other option in that.

If any one phasing the problem here is the solution: the jscroll will stop the loading the content once the 'next page' link is not available.. so please check when you want to stop loading the content then 'next page' link is not getting loaded in the last content which is appended.

Trigger event on animation complete (no control over animation)

I've a scenario that requires me to detect animation stop of a periodically animated element and trigger a function. I've no control over the element's animation. The animation can be dynamic so I can't use clever setTimeout.
Long Story
The simplified form of the problem is that I'm using a third party jQuery sliding banners plugin that uses some obfuscated JavaScript to slide banners in and out. I'm in need of figuring out a hook on slideComplete sort of event, but all I have is an element id. Take this jsfiddle as an example and imagine that the javascript has been obfuscated. I need to trigger a function when the red box reaches the extremes and stops.
I'm aware of the :animated pseudo selector but I think it will need me to constantly poll the required element. I've gone through this, this, and this, but no avail. I've checked jquery promise but I couldn't figure out to use that in this scenario. This SO question is closest to my requirements but it has no answers.
P.S. Some more information that might be helpful:
The element isn't created by JavaScript, it is present on page load.
I've control over when to apply the plugin (that makes it periodically sliding banner) on the element

Most of the slideshow plugins I have used use changing classes at the end of the animation... You could extend the "addClass" method of jQuery to allow you to capture the class change as long as the plugin you use is using that method like it should:
(function($){
$.each(["addClass","removeClass"],function(i,methodname){
var oldmethod = $.fn[methodname];
$.fn[methodname] = function(){
oldmethod.apply( this, arguments );
this.trigger(methodname+"change");
return this;
}
});
})(jQuery);
I threw together a fiddle here
Even with obfuscated code you should be able to use this method to check how they are sending in the arguments to animate (I use the "options" object when I send arguments to animate usually) and wrap their callback function in an anonymous function that triggers an event...
like this fiddle
Here is the relevant block of script:
(function($){
$.each(["animate"],function(i,methodname){
var oldmethod = $.fn[methodname];
$.fn[methodname] = function(){
var args=arguments;
that=this;
var oldcall=args[2];
args[2]=function(){
oldcall();
console.log("slideFinish");
}
oldmethod.apply( this, args );
return this;
}
});
})(jQuery);

Well since you didn't give any indication as to what kind of animation is being done, I'm going to assume that its a horizontal/vertical translation, although I think this could be applied to other effects as well. Because I don't know how the animation is being accomplished, a setInterval evaluation would be the only way I can guess at how to do this.
var prevPos = 0;
var isAnimating = setInterval(function(){
if($(YOUROBJECT).css('top') == prevPos){
//logic here
}
else{
prevPos = $(YOUROBJECT).css('top');
}
},500);
That will evaluate the vertical position of the object every .5 seconds, and if the current vertical position is equal to the one taken .5 seconds ago, it will assume that animation has stopped and you can execute some code.
edit --
just noticed your jsfiddle had a horizontal translation, so the code for your jsfiddle is here http://jsfiddle.net/wZbNA/3/

Mootools Slider plugin functions

I am using mootools to create a CSS skin for the Youtube chromeless player using the javascript API to control playback. I cannot post the code unfortunately. The question I have is a more general one. When using the slider plugin a call to mySlider.set(step) moves the knob to the correct step on the slider but it triggers all of the plugins event functions (onChange, onTick, onComplete). The problem with this is, how do you know if the sliders knob position was changed by a user or a call to the set() function? I would have thought there would be a function reserved for when the knob was released by a mouse only and not be called if the position was simply set in code. I have code that updates the knobs position based on where the videos playback duration is currently at. I need to be able to move the knob to the current position in code without it thinking a user let go of the knob.
To simplify the question, is there a way to set the knobs position on a slider in code without triggering the functions used when a user interacts?
You can find the Slider plugin reference here http://mootools.net/docs/more/Drag/Slider
Thanks

I got this problem and ended up doing this
var slider = new Slider(track,knob, {
onChange: function(){
console.log("doesn't fire after autosize()");
}
});
// fake .set();
slider.step = 50; // new value
slider.autosize(); // redraw the knob

Make a variable that indicates that you're setting it programatically, then skip your event handlers if the variable is true.
Then, each time you set the slider in code, set the variable to true first, then back to false afterwords in a finally block.

Javascript/JQuery: Gallery with very large images. How can I have it on click fade out, load the next image, and then fade in w/ the new image?

my boss has me working on a website that basically has a very large gallery right in the middle.
The way this one part needs to work is that the user clicks a next/prev button, the image fades out, displays a loading spinning image gif, and then fades in with the new image when it's down downloading. I have no idea where to even begin.
I know jquery somewhat, but I'm very new to actual javascript. My only reference book at hand is a copy of "Javascript for Dummies" for 1997. Is this of any use to me at all, or has Javascript changed since then?

There are lots of jQuery plugin for image gallery: Galleria, GalleryView, Pikachoose, and this one.
Or you can search from jQuery plugins page.

Please get a newer book, or just use the web as a resource, any info. from 1997 is going to be horribly outdated.
This is a very simple site I've recommended to beginners before: http://htmldog.com/guides/javascript/
No, it doesn't cover everything, but that's what's good about it, you'll get some key things down, and then be able to search on google for more specific stuff.
To give you some barebones ot start with, I would do something like this:
$(document).ready(function() {
$('#nextBtn').click(function() {
transitionToNextImage ();
});
});
transitionToNextImage = function() {
$('img.active-image').fadeTo(1000,0), function() {
// fade out complete.
$('#inProgressGif').show();
getNextImage();
});
};
getNextImage = function() {
// make ajax call to get new image, and
// in the success callback of the ajax call,
// remove the inProgressGif, and
// add the image ot the DOM with opacity 0,
// then slowly fade it in to opacity 1 (opposite
// of what was done above
};

How to show a spinner while loading an image via JavaScript

I'm currently working on a web application which has a page which displays a single chart (a .png image). On another part of this page there are a set of links which, when clicked, the entire page reloads and looks exactly the same as before except for the chart in the middle of the page.
What I want to do is when a link is clicked on a page just the chart on the page is changed. This will speed things up tremendously as the page is roughly 100kb large, and don't really want to reload the entire page just to display this.
I've been doing this via JavaScript, which works so far, using the following code
document.getElementById('chart').src = '/charts/10.png';
The problem is that when the user clicks on the link, it may take a couple of seconds before the chart changes. This makes the user think that their click hasn't done anything, or that the system is slow to respond.
What I want to happen is display a spinner / throbber / status indicator, in place of where the image is while it is loading, so when the user clicks the link they know at least the system has taken their input and is doing something about it.
I've tried a few suggestions, even using a psudo time out to show a spinner, and then flick back to the image.
A good suggestion I've had is to use the following
<img src="/charts/10.png" lowsrc="/spinner.gif"/>
Which would be ideal, except the spinner is significantly smaller than the chart which is being displayed.
Any other ideas?

I've used something like this to preload an image and then automatically call back to my javascript when the image is finished loading. You want to check complete before you setup the callback because the image may already be cached and it may not call your callback.
function PreloadImage(imgSrc, callback){
var objImagePreloader = new Image();
objImagePreloader.src = imgSrc;
if(objImagePreloader.complete){
callback();
objImagePreloader.onload=function(){};
}
else{
objImagePreloader.onload = function() {
callback();
// clear onLoad, IE behaves irratically with animated gifs otherwise
objImagePreloader.onload=function(){};
}
}
}

You could show a static image that gives the optical illusion of a spinny-wheel, like these.

Using the load() method of jQuery, it is easily possible to do something as soon as an image is loaded:
$('img.example').load(function() {
$('#spinner').fadeOut();
});
See: http://api.jquery.com/load-event/

Use the power of the setTimeout() function (More info) - this allows you set a timer to trigger a function call in the future, and calling it won't block execution of the current / other functions (async.).
Position a div containing the spinner above the chart image, with it's css display attribute set to none:
<div> <img src="spinner.gif" id="spinnerImg" style="display: none;" /></div>
The nbsp stop the div collapsing when the spinner is hidden. Without it, when you toggle display of the spinner, your layout will "twitch"
function chartOnClick() {
//How long to show the spinner for in ms (eg 3 seconds)
var spinnerShowTime = 3000
//Show the spinner
document.getElementById('spinnerImg').style.display = "";
//Change the chart src
document.getElementById('chart').src = '/charts/10.png';
//Set the timeout on the spinner
setTimeout("hideSpinner()", spinnerShowTime);
}
function hideSpinner() {
document.getElementById('spinnerImg').style.display = "none";
}

Use CSS to set the loading animation as a centered background-image for the image's container.
Then when loading the new large image, first set the src to a preloaded transparent 1 pixel gif.
e.g.
document.getElementById('mainimg').src = '/images/1pix.gif';
document.getElementById('mainimg').src = '/images/large_image.jpg';
While the large_image.jpg is loading, the background will show through the 1pix transparent gif.

Building on Ed's answer, I would prefer to see something like:
function PreLoadImage( srcURL, callback, errorCallback ) {
var thePic = new Image();
thePic.onload = function() {
callback();
thePic.onload = function(){};
}
thePic.onerror = function() {
errorCallback();
}
thePic.src = srcURL;
}
Your callback can display the image in its proper place and dispose/hide of a spinner, and the errorCallback prevents your page from "beachballing". All event driven, no timers or polling, plus you don't have to add the additional if statements to check if the image completed loading while you where setting up your events - since they're set up beforehand they'll trigger regardless of how quickly the images loads.

Some time ago I have written a jQuery plugin which handles displaying a spinner automatically http://denysonique.github.com/imgPreload/
Looking in to its source code should help you with detecting when to display the spinner and with displaying it in the centre of the loaded image.

I like #duddle's jquery method but find that load() isn't always called (such as when the image is retrieved from cache in IE). I use this version instead:
$('img.example').one('load', function() {
$('#spinner').remove();
}).each(function() {
if(this.complete) {
$(this).trigger('load');
}
});
This calls load at most one time and immediately if it's already completed loading.

put the spinner in a div the same size as the chart, you know the height and width so you can use relative positioning to center it correctly.

Aside from the lowsrc option, I've also used a background-image on the img's container.

Be aware that the callback function is also called if the image src doesn't exist (http 404 error). To avoid this you can check the width of the image, like:
if(this.width == 0) return false;

#iAn's solution looks good to me. The only thing I'd change is instead of using setTimeout, I'd try and hook into the images 'Load' event. This way, if the image takes longer than 3 seconds to download, you'll still get the spinner.
On the other hand, if it takes less time to download, you'll get the spinner for less than 3 seconds.

I would add some random digits to avoid the browser cache.