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lightbox onclick change src then change back

I am using Materialize CSS and have the "Material Box" which is a lightbox plugin. I want all of the thumbnails to be the same size. When clicked I want the full photo to load.
I am using onclick to change the src. How do I change it back to the thumbnail when the large photo closes (either with a click or the escape key)?
<div class="col s6 m3">
<img class="materialboxed responsive-img" src="images/thumb1.jpg" onclick='this.src="images/photo1"'>
</div>
Material Box Javascript
document.addEventListener('DOMContentLoaded', function() {
var elems = document.querySelectorAll('.materialboxed');
var options = {}
var instances = M.Materialbox.init(elems, options);
});
// Or with jQuery
$(document).ready(function(){
$('.materialboxed').materialbox();
});
Materializecss.com - https://materializecss.com/media.html
I haven't found an easy other way of achieving the lightbox effect with cropped square thumbnails. Any advice would be greatly appreciated!

Here is one implementation of what you want, keeping track of the image click state.
$(document).ready(function(){
$('.materialboxed').materialbox();
// Image sources
const srcThumb = '/images/thumb1.jpg'
const srcPhoto = '/images/photo1.jpg'
// Click state
var clicked = false
// Get image element and bind click event
const img = $('.materialboxed')
img.on('click', function() {
img.attr('src', clicked ? srcPhoto : srcThumb)
clicked = !clicked
})
});

No need to rely on onclick in this case.
Materialize is already binding onclick for those images.
And it provides the following native methods we can use for doing exactly what you want using pure JS (no jQuery):
onOpenStart Function null Callback function called before materialbox is opened.
onCloseEnd Function null Callback function called after materialbox is closed.
In this example below, we assume there is a normal materialboxed photo gallery containing thumbnails named thumb_whatever.jpg, for example. But we're also serving the original sized photo named whatever.jpg in the same directory.
Then we're changing src attribute dynamically removing the thumb_ prefix to get the original image, which in this case will be imediately lightboxed by materialize.
And after closing the lightbox, the src attribute is being set back again without the thumb_ prefix.
We do that while initializing Materialbox:
// Initializing Materialbox
const mb = document.querySelectorAll('.materialboxed')
M.Materialbox.init(mb, {
onOpenStart: (el) => {
var src = el.getAttribute('src') // get the src
var path = src.substring(0,src.lastIndexOf('/')) // get the path from the src
var fileName = src.substring(src.lastIndexOf('/')).replace('thumb_','') // get the filename and removes 'thumb_' prefix
var newSrc = path+fileName // re-assemble without the 'thumb_' prefix
el.setAttribute('src', newSrc)
},
onCloseEnd: (el) => {
var src = el.getAttribute('src') // get the src
var path = src.substring(0,src.lastIndexOf('/')) // get the path from the src
var fileName = src.substring(src.lastIndexOf('/')).replace('/', '/thumb_') // get the filename and adds 'thumb_' prefix
var newSrc = path+fileName // re-assemble with the 'thumb_' prefix
el.setAttribute('src', newSrc)
}
})
This solution is also working like a charm for me, crossplatform.

Change class on multiple img in array

This is my first post here, I always found solutions on this page, so thank you for that.
I have a problem with .removeClass and .addClass in my last program.
I load multiple pictures into array Frames and I want change all (previous-image) to (current-image) in frames[0]. Here is my code, it is change class only on second image. Here is code:
function loadImage() {
// Creates a new <li>
var li = document.createElement("li");
// Generates the image file name using the incremented "loadedImages" variable
var imageName = "graphics/img/Dodge_Viper_SRT10_2010_360_720_50-" + (loadedImages + 1) + ".jpg";
var imageName1 = "graphics/img/Dodge_Viper_SRT10_2010_360_720_50-" + (loadedImages + 1) + ".jpg";
/*
Creates a new <img> and sets its src attribute to point to the file name we generated.
It also hides the image by applying the "previous-image" CSS class to it.
The image then is added to the <li>.
*/
var image = $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li) && $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li);
// We add the newly added image object (returned by jQuery) to the "frames" array.
frames.push(image);
// We add the <li> to the <ol>
$images.append(li);
/*
Adds the "load" event handler to the new image.
When the event triggers it calls the "imageLoaded" function.
*/
$(image).load(function() {
imageLoaded();
});
};
function imageLoaded() {
// Increments the value of the "loadedImages" variable
loadedImages++;
// Updates the preloader percentage text
$("#spinner span").text(Math.floor(loadedImages / totalFrames * 100) + "%");
// Checks if the currently loaded image is the last one in the sequence...
if (loadedImages == totalFrames) {
// ...if so, it makes the first image in the sequence to be visible by removing the "previous-image" class and applying the "current-image" on it
frames[0].removeClass("previous-image").addClass("current-image");
/*
Displays the image slider by using the jQuery "fadeOut" animation and its complete event handler.
When the preloader is completely faded, it stops the preloader rendering and calls the "showThreesixty" function to display the images.
*/
$("#spinner").fadeOut("slow", function() {
spinner.hide();
showThreesixty();
});
} else {
// ...if not, Loads the next image in the sequence
loadImage();
}
};
This is, how it looks in browser:
<ol><li><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="previous-image"><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="light-image current-image"></li></ol>
This is, what I want:
<ol><li><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="current-image"><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="light-image current-image"></li></ol>
When I change this
var image = $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li) && $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li);
to this
var image = $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li) && $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li);
it still change only second img. Any help?

var image = $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li) && $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li);
is not doing what you think it is. It's only using the second element you declare. They both get appended to the page (because the appendTo method runs), but && is a logical operator, it's not used for concatenation, so the variable "image" only contains the second image you declared.
This will work instead:
var image = $('<img>', { "src": imageName, "class": "previous-image" });
image = image.add($('<img>', { "src": imageName1, "class": "previous-image light-image" }));
image.appendTo(li);

If you are just trying to replace all the previous-image classes with current image then you can do this:
$('img.previous-image').each(function(){
$(this).addClass("current-image").removeClass("previous-image");
});

Using local storage to change CSS background image

I have a little trouble with a JavaScript piece of code.
The code is as it follows:`
$(switchBackground);
var oFReader = new FileReader(),
rFilter = /^(?:image\/bmp|image\/cis\-cod|image\/gif|image\/ief|image\/jpeg|image\/jpeg|image\/jpeg|image\/pipeg|image\/png|image\/svg\+xml|image\/tiff|image\/x\-cmu\-raster|image\/x\-cmx|image\/x\-icon|image\/x\-portable\-anymap|image\/x\-portable\-bitmap|image\/x\-portable\-graymap|image\/x\-portable\-pixmap|image\/x\-rgb|image\/x\-xbitmap|image\/x\-xpixmap|image\/x\-xwindowdump)$/i;
oFReader.onload = function(oFREvent) {
localStorage.setItem('b', oFREvent.target.result);
switchBackground();
};
function switchBackground() {
var backgroundImage = localStorage.getItem('b');
if (backgroundImage) {
$('#profile').css('background-image', 'url(' + backgroundImage + ')');
}
}
function loadImageFile(testEl) {
if (! testEl.files.length) { return; }
var oFile = testEl.files[0];
if (!rFilter.test(oFile.type)) { alert("You must select a valid image file!"); return; }
oFReader.readAsDataURL(oFile);
}
`
And my problem is the following, as I don't have almost any knowledge in JavaScript I'm having a hard time figuring out how to clone that code.
I have 2 <div>'s - one with id="profile" and the other with id="start-menu", I want the users of my web page to be able to change the background image of both <div>'s but untill now I have only been able to change the <div> with the id="profile". And the way that they change those backgrounds is through an input button, more exactly this one:
<input id="test" type="file" onchange="loadImageFile(this)" />
I have already tried adding some other characters to some of the functions names, and then just change id="test2" or onchange="loadImageFile2(this), but untill now I haven't been successful.
By the way, I should mention that I don't want the backgrounds to be changed with the same button, there are 2 diffrent input buttons, both with the same structure as above (except for the function calling they are almost the same).
What exactly do I need to change at the JS code above in order for it to work with both div's? Please be at your clearest when writing an answer, as my primar language is not english and sometimes I understand certaint phrases a bit harder.

This line is the important one:
$('#profile').css('background-image', 'url(' + backgroundImage + ')');
See the #profile part? That is a selector. That is telling the browser to change the background for the div with ID=profile. If you changed that to this:
$('#start-menu').css('background-image', 'url(' + backgroundImage + ')');
Then it would update the other div.
If you want it to update the two divs with the same images just do this:
function switchBackground() {
var backgroundImage = localStorage.getItem('b');
if (backgroundImage) {
$('#profile').css('background-image', 'url(' + backgroundImage +')');
$('#start-menu').css('background-image', 'url(' + backgroundImage +')');
}
}
If you wanted them to be separate images then you'd have to amend the switchBackground function to accept a parameter for which div to switch.

how to swap image on clicking on image?

Here I use two images. when i click once on the Sort_down.png image then it changes to Sort_up.png.
When I click on this image again it is not changing back to Sort_down.png, how can I achieve this ?
<script type="text/javascript">
function clkimg() {
var img = document.getElementById('stCodeDSC');
img.src = '../Images/sort_up.png';
}
</script>
<td width="11%" bgcolor="#C5DEFF" class="menu_header">
<div align="center" onclick="clkimg();" >
<img name="stCodeDSC" class="img" src="../Images/Sort_down.png" id="stCodeDSC">
</div>
</td>

Depending on the browser you're using, when the source of an image is set to a relative URL, reading it back will give you the absolute URL. If you want to use a toggle, you can check for a string in the source, for example:
function clkimg() {
var img = document.getElementById('stCodeDSC'),
nextImg = img.src.indexOf('up.png')>0 ? 'down':'up';
img.src = '../Images/sort_' + nextImg + '.png';
}
If the sort_up and sort_down images are actually icons just identifying the up or down state of the current sort, you can combine the two images into one and use them as a sprite that you display using CSS. More details will be available at https://stackoverflow.com/search?q=css+sprite

You aren't telling it to sort down. In your click code you'll need to test if the image is showing up or down and change it accordingly. Something like:
if(img.src === '../Images/sort_up.png')
img.src = '../Images/sort_down.png';
else
img.src = '../Images/sort_up.png';
Generally, however, this would be better handled by adding or removing a class on click and styling the class using css.

jQuery find height of an image even if it is not set in the HTML

I have, what I think is, a strange issue. I am running a simple query that finds the largest image on a page. Here is some test data - all images are 32x32 but one is sized to 300x300.
<img src="app/assets/images/icons/blue.png" />
<img src="app/assets/images/icons/error.png"/>
<img src="app/assets/images/icons/info.png" height="300" width="300"/>
If I run a simple query like this:
$('img').each(function(){
console.log($(this).height());
});
I will get 0,0,300 — and not 32,32,300.
Can anyone point me to a better method of finding the size the image is being rendered at?
Thanks.

If the image is "natively" sized, i.e. no width or height are present in the HTML, you'll need to wait for the image to load before you know its size. I use this:
jQuery("img").each(function(){
var img = jQuery(this);
if (img.attr("complete")) {
console.log(img.height());
} else {
img.load(function(){
console.log(img.height());
});
}
});

Make sure you do it after the image is ready in $(img).load(), then it will work. Try JavaScript to verify:
function iLoad(isrc) {
var oImg = new Image();
oImg.src = isrc;
if (oImg.complete) {
window.alert(oImg.src + ' ' + oImg.width + ' x ' + oImg.height);