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Disable Touch on Materialize Carousel

It looks like no one has asked this question before since I've pretty much scoured the internet looking for a very simple answer.
How would one go about disabling the ability to swipe left/right on the materialize carousel?

in Materialize.js add/edit:
var allowCarouselDrag = true;
value: function _handleCarouselDrag(e) {
if(allowCarouselDrag){
....
}
}
You can set the allowCarouselDrag variable per application.

I solved it like this
// Create carouser
$('#carousel').carousel({
fullWidth: true,
indicators: false,
duration: 100,
});
// Get instance of carousel
carouselInstance = M.Carousel.getInstance(sliderDOM);
// Remove event listeners added by Materialize for corousel
document.getElementById("carousel").removeEventListener('mousedown', carouselInstance._handleCarouselTapBound);
document.getElementById("carousel").removeEventListener('mousemove', carouselInstance._handleCarouselDragBound);
document.getElementById("carousel").removeEventListener('mouseup', carouselInstance._handleCarouselReleaseBound);
document.getElementById("carousel").removeEventListener('mouseleave', carouselInstance._handleCarouselReleaseBound);
document.getElementById("carousel").removeEventListener('click', carouselInstance._handleCarouselClickBound);
After that drag/swipe is disabled and you can still change page/item via
carouselInstance.set(0);
and
carouselInstance.next(0);

This is far from a perfect solution, and it might disable too much of the functionality in your case, I'm not sure. An option to turn this on/off would be much appreciated.
But for my needs, turning off the events on the carousel did the job:
var carousel = $('.carousel.carousel-slider').carousel();
// Disable all swipping on carousel
if (typeof window.ontouchstart !== 'undefined') {
carousel.off('touchstart.carousel');
}
carousel.off('mousedown.carousel');

function tap(e) {
pressed = true;
dragged = false;
vertical_dragged = true;
reference = xpos(e);
referenceY = ypos(e);
velocity = amplitude = 0;
frame = offset;
timestamp = Date.now();
clearInterval(ticker);
ticker = setInterval(track, 100);
}

I have attempted to solve this problem for the past ~three days and have come to the conclusion that there is no clean solution other than directly editing the materialize.js file as in Lester's answer. Unfortunately, this is not an ideal solution as it causes issues when updating Materialize etc.
The simplest solution that I have come up with after this time is the following piece of javascript:
window.onload = function() {
window.mouseDownNow = false;
// The selector below must be more specific than .carousel.carousel-slider in
// order for the event to be cancelled properly.
$('.class-added-to-block-swiping-functionality')
.mousedown(function() {
window.mouseDownNow = true;
})
.mousemove(function(event) {
if(window.mouseDownNow) {
event.stopPropagation();
}
})
.mouseup(function() {
window.mouseDownNow = false;
});
};
This will simply stop the event from bubbling to the Materialize swiping functionality.
Note: I am not sure how specific the selector must be, mine were classes that were specific to text areas.

building a Jquery Tool slider like yahoo.com slider details

Hi im trying to achieve a "news slider" like the one you can see in yahoo.com... I almost have the 100% of the code.. (if you want to compare them here is my code http://jsfiddle.net/PcAwU/1/)
what is missing in my code , (forget about design) is that , In my slider you have to clic on each item, i tried to replace Onclick for Hover on the javascript, it worked, but the fisrt image on the gallery stop working, so when you just open the slider, you see a missing image.
Other point.. also very important, in yahoo.com after "x seconds" the slider goes to the next item, and so on ... all the Thumnails are gruped 4 by for 4, (in mine 5 by 5, thats ok) ... after pass all the 4 items, it go to the next bloc..
HOW CAN I ACHIEVE THAT!!. I really looked into the API, everything, really im lost, i hope someone can help me. cause im really lost in here.
Thanks
Here is the script
$(function() {
var root = $(".scrollable").scrollable({circular: false}).autoscroll({ autoplay: true });
$(".items img").click(function() {
// see if same thumb is being clicked
if ($(this).hasClass("active")) { return; }
// calclulate large image's URL based on the thumbnail URL (flickr specific)
var url = $(this).attr("src").replace("_t", "");
// get handle to element that wraps the image and make it semi-transparent
var wrap = $("#image_wrap").fadeTo("medium", 0.5);
// the large image from www.flickr.com
var img = new Image();
// call this function after it's loaded
img.onload = function() {
// make wrapper fully visible
wrap.fadeTo("fast", 1);
// change the image
wrap.find("img").attr("src", url);
};
// begin loading the image from www.flickr.com
img.src = url;
// activate item
$(".items img").removeClass("active");
$(this).addClass("active");
// when page loads simulate a "click" on the first image
}).filter(":first").click();
// provide scrollable API for the action buttons
window.api = root.data("scrollable");
});
function toggle(el){
if(el.className!="play")
{
el.className="play";
el.src='images/play.png';
api.pause();
}
else if(el.className=="play")
{
el.className="pause";
el.src='images/pause.png';
api.play();
}
return false;
}

To fix the hover problem you need to make some quick changes: Change the click to a on(..) similar to just hover(..) just the new standard.
$(".items img").on("hover",function() {
....
Then You need to update the bottom click event to mouse over to simulate a hover effect. Trigger is a comman function to use to trigger some event.
}).filter(":first").trigger("mouseover");
jSFiddle: http://jsfiddle.net/PcAwU/2/
Now to have a play feature, you need a counter/ and a set interval like so:
var count = 1;
setInterval(function(){
count++; // add to the counter
if($(".items img").eq(count).length != 0){ // eq(.. select by index [0],[1]..
$(".items img").eq(count).trigger("mouseover");
} else count = 0; //reset counter
},1000);
This will go show new images every 1 second (1000 = 1sec), you can change this and manipulate it to your liking.
jSFiddle: http://jsfiddle.net/PcAwU/3/
If you want to hover the active image, you need to do so with the css() or the addClass() functions. But You have done this already, All we have to do is a simple css change:
.scrollable .active {
....
border-bottom:3px solid skyblue;
Here is the new update jSFilde: http://jsfiddle.net/PcAwU/4/

onmouseout and onmouseover

I am working on homework that involves working with javascript. Part of my homework assignment is to use the event handlers onmouseout and onmouseouver. What is supposed to happen when the user hovers over a specific div element, the font size grows by 25%, and when the user mouses out of the div element, the font size goes back to normal. My question is, is it possible to incorporate both an onmouseover function and an onmouseout function into one function? Somehow that is what my teacher wants us to do. I have this started so far.
function FontSize(x)
{
x.style.fonstSize = large;
}
I'm also thinking this isnt the correct code to make the font 25% larger, but I'm not sure how to really incorporate an onmouseout in this function.

As a teacher myself, I am 99% sure that by "one function" the instructor means one general-purpose function to change the font size, not one function which uses conditional statements to work backwards and figure out whether it should be doing onmouseout or onmouseover.
Your script should contain:
function resize(elem, percent) { elem.style.fontSize = percent; }
Your HTML should contain:
<div onmouseover="resize(this, '125%')" onmouseout="resize(this, '100%')"
Text within div..
</div>
Note: Situations such as here, are exactly why JavaScript has the keyword "this"--to save us from needing to use complicated document.getElementById() statements.

You can use "%" property for controlling font-size as described here with the following code.
document.getElementById("div1").onmouseover = function() {
document.getElementById("div1").style.fontSize = "125%"
};
document.getElementById("div1").onmouseout = function() {
document.getElementById("div1").style.fontSize = "100%";
};
Here is the working jsfiddle : http://jsfiddle.net/LxhdU/

Yes you can. Call the same function on both events, and pass a parameter to indicate whether the fontsize should increase or decrease.
ChangeFontSize = function(element, shouldIncreaseFontsize)
{
var small=14;
var large = small * 1.25;
if(shouldIncreaseFontsize) {
element.style.fontSize = large + "px";
}
else {
element.style.fontSize = small + "px";
}
}
http://jsfiddle.net/TMHbW/1/

I'd do something simple like the following. The large and small values can be whatever you need them to be for the font size to work or they can be variables you've defined in prior code.
Demo: http://jsfiddle.net/lucuma/EAbYn/
function doHover(e) {
if (e.type=='mouseover') {
this.style.fontSize = "large";
} else {
this.style.fontSize = "small";
}
}
var el = document.getElementById('myelement')
el.onmouseout =doHover;
el.onmouseover=doHover;

It is possible you do not need to call both the events on the element explicitly instead extension you create will do that.Extend the Element's prototype. Jquery also does similar to this.
Ref Prototype
See Fiddle:- http://jsfiddle.net/4fs7V/
Element.prototype.hover= function( fnOver, fnOut ) {
this.onmouseover=fnOver;
this.onmouseout=fnOut || fnOver;
return this;
};
document.getElementById('test').hover(function(){
//do your mouseover stuff
},
function(){
//do your mouseout stuff
});
Update
Same can be achieved with just one function too:-
Hover me
.largeFont {
font-size:125%;
}
Element.prototype.hover = function (fnOver, fnOut) {
this.onmouseover = fnOver;
this.onmouseout = fnOut || fnOver;
return this;
};
document.getElementById('test').hover(changeMe);
function changeMe()
{
if(this.hasAttribute('class'))
{
this.removeAttribute('class');
}
else
{
this.setAttribute('class', 'largeFont');
}
}

how to make a <div> appear in slow motion

I want the javascript code to show a div in slow motion.
function showDiv(divID)
{
if(document.getElementById(divID).style.display=='none')
{
document.getElementById(divID).style.display='block';
}
}
Here div appears, but not in slow motion. Can anyone help ??
Thanks in advance
Dev..

There is no need of jQuery in this atall , its just a basic I am using your function to explain how thats done.
function showDiv(divID)
{
if(document.getElementById(divID).style.display=='none')
{
document.getElementById(divID).style.display='block';
}
}
What your function is doing is basically removing the whole Element from BOX Model ( the toggle of block and none removes the element totally from the BOX Model so it doesnt occupies any space or anything , this but may / may not cause some layout issues );
Now to animate it in slow motion you need a timing function.
a timing function is a simple mathematical function which gives the value of the property ( opacity in your case ) for a given time or depending on other parameters .
Other then that you also need to use properties like opacity in order to fade it (Opacity is a CSS property that defines the transparency of an element and its childrens )
So let us begin with a very basic show / hide using setTimeout Function in JS.
function getValue(t,dir){
if( dir > 0){
return 0.5*t; /* Y = mx + c */
}else{
return 1-(0.5*t);
}
/*
Here the slope of line m = 0.5.
t is the time interval.
*/
}
function animator(divID){
if(!(this instanceof animator)) return new animator(divID); /* Ignore this */
var Node = document.getElementById(divID),
start = new Date.getTime(), // The initiation.
now = 0,
dir = 1,
visible = true;
function step( ){
now = new Date.getTime();
var val = getValue( now - start,dir)
Node.style.opacity = val;
if( dir > 0 && val > 1 || dir < 0 && val < 0 ){
visible = !(visible*1);
// Optionally here u can call the block & none
if( dir < 0 ) { /* Hiding and hidden*/
Node.style.display = 'none'; // So if were repositioning using position:relative; it will support after hide
}
/* Our animation is finished lets end the continous calls */
return;
}
setTimeout(step,100); // Each step is executated in 100seconds
}
this.animate = function(){
Node.style.display = 'block';
dir *= -1;
start = new Date.getTime();
setTimeout(step,100);
}
}
now you can simply call the function
var magician = new animator('divName');
then toggle its animation by
magician.animate();
Now playing with the timing function you can create whatever possibilities you want as in
return t^2 / ( 2 *3.23423 );
or even higher polynomial equations like
return t^3+6t^2-38t+12;
As you can see our function is very very basic but it explains the point of how to make animations using pure js . you can later on use CSS3 module for animation and trigger those classes with javascript :-)
Or perhaps write a cross browser polyfill using CSS3 where available ( it is faster ) , and JS if not :-) hope that helps

Crossbrowser solution (without jQuery) :
HTML :
<div id="toChange" ></div>
CSS :
#toChange
{
background-color:red;
width:200px;
height:200px;
opacity:0;//IE9, Firefox, Chrome, Opera, and Safari
filter:alpha(opacity=0);//IE8 and earlier
}
Javascript :
var elem=document.getElementById("toChange");
var x=0;
function moreVisible()
{
if(x==1)clearInterval(t);
x+=0.05;
elem.style.opacity=x;
elem.style.filter="alpha(opacity="+(x*100)+")";
}
var t=setInterval(moreVisible,25);
Fiddle demonstration : http://jsfiddle.net/JgxW6/1/

So you have a few jQuery answers but I wouldn't recommend jQuery if fading the div is all you want.
Certainly jQuery makes things easier but it is a lot of overhead for a single simple functionality.
Here is someone that did it with pure JS:
Fade in and fade out in pure javascript
And a CSS3 example:
How to trigger CSS3 fade-in effect using Javascript?

You can use jquery $.show('slow') for the same, if you want to do the same without using jquery then you might be required to code something to show the effect yourself, you may have a look at source of jquery's show function http://james.padolsey.com/jquery/#v=1.6.2&fn=show . alternatively , you can also use fadein() for fade in effect in jquery

Yes you can do it using Jquery. Here is my sample example
$('#divID').click(function() {
$('#book').show('slow', function() {
// Animation complete.
});
});
For details clik here
Thanks.

How to improve image cross-fade performance?

I want to be able to do a cross fade transition on large images whose width is set to 100% of the screen. I have a working example of what I want to accomplish. However, when I test it out on various browsers and various computers I don't get a buttery-smooth transition everywhere.
See demo on jsFiddle: http://jsfiddle.net/vrD2C/
See on Amazon S3: http://imagefader.s3.amazonaws.com/index.htm
I want to know how to improve the performance. Here's the function that actually does the image swap:
function swapImage(oldImg, newImg) {
newImg.css({
"display": "block",
"z-index": 2,
"opacity": 0
})
.removeClass("shadow")
.animate({ "opacity": 1 }, 500, function () {
if (oldImg) {
oldImg.hide();
}
newImg.addClass("shadow").css("z-index", 1);
});
}
Is using jQuery animate() to change the opacity a bad way to go?

You might want to look into CSS3 Transitions, as the browser might be able to optimize that better than Javascript directly setting the attributes in a loop. This seems to be a pretty good start for it:
http://robertnyman.com/2010/04/27/using-css3-transitions-to-create-rich-effects/

I'm not sure if this will help optimize your performance as I am currently using IE9 on an amped up machine and even if I put the browser into IE7 or 8 document mode, the JavaScript doesn't falter with your current code. However, you might consider making the following optimizations to the code.
Unclutter the contents of the main photo stage by placing all your photos in a hidden container you could give an id of "queue" or something similar, making the DOM do the work of storing and ordering the images you are not currently displaying for you. This will also leave the browser only working with two visible images at any given time, giving it less to consider as far as stacking context, positioning, and so on.
Rewrite the code to use an event trigger and bind the fade-in handling to the event, calling the first image in the queue's event once the current transition is complete. I find this method is more well-behaved for cycling animation than some timeout-managed scripts. An example of how to do this follows:
// Bind a custom event to each image called "transition"
$("#queue img").bind("transition", function() {
$(this)
// Hide the image
.hide()
// Move it to the visible stage
.appendTo("#photos")
// Delay the upcoming animation by the desired value
.delay(2500)
// Slowly fade the image in
.fadeIn("slow", function() {
// Animation callback
$(this)
// Add a shadow class to this image
.addClass("shadow")
// Select the replaced image
.siblings("img")
// Remove its shadow class
.removeClass("shadow")
// Move it to the back of the image queue container
.appendTo("#queue");
// Trigger the transition event on the next image in the queue
$("#queue img:first").trigger("transition");
});
}).first().addClass("shadow").trigger("transition"); // Fire the initial event
Try this working demo in your problem browsers and let me know if the performance is still poor.

I had the same problem too. I just preloaded my images and the transitions became smooth again.

The point is that IE is not W3C compliant, but +1 with ctcherry as using css is the most efficient way for smooth transitions.
Then there are the javascript coded solutions, either using js straight (but need some efforts are needed to comply with W3C Vs browsers), or using libs like JQuery or Mootools.
Here is a good javascript coded example (See demo online) compliant to your needs :
var Fondu = function(classe_img){
this.classe_img = classe_img;
this.courant = 0;
this.coeff = 100;
this.collection = this.getImages();
this.collection[0].style.zIndex = 100;
this.total = this.collection.length - 1;
this.encours = false;
}
Fondu.prototype.getImages = function(){
var tmp = [];
if(document.getElementsByClassName){
tmp = document.getElementsByClassName(this.classe_img);
}
else{
var i=0;
while(document.getElementsByTagName('*')[i]){
if(document.getElementsByTagName('*')[i].className.indexOf(this.classe_img) > -1){
tmp.push(document.getElementsByTagName('*')[i]);
}
i++;
}
}
var j=tmp.length;
while(j--){
if(tmp[j].filters){
tmp[j].style.width = tmp[j].style.width || tmp[j].offsetWidth+'px';
tmp[j].style.filter = 'alpha(opacity=100)';
tmp[j].opaque = tmp[j].filters[0];
this.coeff = 1;
}
else{
tmp[j].opaque = tmp[j].style;
}
}
return tmp;
}
Fondu.prototype.change = function(sens){
if(this.encours){
return false;
}
var prevObj = this.collection[this.courant];
this.encours = true;
if(sens){
this.courant++;
if(this.courant>this.total){
this.courant = 0;
}
}
else{
this.courant--;
if(this.courant<0){
this.courant = this.total;
}
}
var nextObj = this.collection[this.courant];
nextObj.style.zIndex = 50;
var tmpOp = 100;
var that = this;
var timer = setInterval(function(){
if(tmpOp<0){
clearInterval(timer);
timer = null;
prevObj.opaque.opacity = 0;
nextObj.style.zIndex = 100;
prevObj.style.zIndex = 0;
prevObj.opaque.opacity = 100 / that.coeff;
that.encours = false;
}
else{
prevObj.opaque.opacity = tmpOp / that.coeff;
tmpOp -= 5;
}
}, 25);
}