How can I prevent jQuery prepend() removing the HTML? - javascript

When I click on the anchor tag, the image shifts from div#left to div#right. I want the image to be copied. Is this the default behaviour of prepend()? How can I avoid this problem?
The image is just a placeholder for a big div with many children.
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<script src="Scripts/jquery-2.1.0.min.js"></script>
<script type="text/javascript" src="Scripts/JavaScript.js"></script>
</head>
<body>
<div id="left" style="float:left">
<img src="Images/Rooms/K1.jpg" alt="Alternate Text" height="200" width="200"/>
</div>
<div id="right" style="float:right"></div>
<a id="addImageToRight" href="#">Add Image toRight</a>
</body>
</html>
The jQuery is:
$(document).ready(function () {
$("#addImageToRight").click(function () {
var $image = $("#left img");
var imgCopy = $image;
$("div#right").prepend(imgCopy);
});
});

Is this the default behaviour of prepend()?
Yes. Putting a DOM node somewhere in the document requires removing it from wherever in the document it is already. It can't exist in two places at the same time.
var imgCopy = $image;
That copies the value of $image to imgCopy. The value is a reference to the object. (In JavaScript, variables can only every hold references to objects).
How to avoid this problem?
Create a copy of the DOM node. Call .clone() on the jQuery object and prepend the return value.
var imgCopy = $image.clone();

You need to update your code from
var $image = $("#left img");
var imgCopy = $image;
to
var imgCopy = $("#left img").clone();
For reference - http://plnkr.co/edit/R5yjTY06dKkqccwmxS62?p=preview

Perhaps take a look at jQuery's clone() to create a copy of the img element.

Related

I cannot add images to the canvas of my thumbnail image gallery

I'm new to html and javascript. I am trying to add images to a canvas when clicked on by calling the image from the image gallery. I'm using the onclick method to my script and isn't working thus I am struggling. I've added my code below. Thank you for your help! The assignment ask...
Implement the imgOnClick(elmt) function so that it paints (to the canvas' drawImage() method) the image given by elmt. elmt will be an tag object. The canvas has the id imgresult.
In the document ready function, have each of the thumbnail images set their click event to the imgOnClick() function. I recommend you test this for one image before implementing it for the remaining images. Make sure you scale the image to a usable size.
<pre> <code><!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<link rel=stylesheet type="text/css" href="memeory.css">
<title>Meme-ory :: Javascript Meme Generator</title>
<script type="application/javascript" src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
<script>
$( document ).ready(function() {
$('.thumbnail').click(imgOnClick('img'){
});
});
function imgOnClick('img') {
var canvas = document.getElementById("imgresult");
var ctx = canvas.getContext("2d");
var img = document.getElementById("closeenough");
ctx.drawImage(img, 10, 10);
};
};
function buttonOnClick() {
};
</script>
</head>
<body>
<header>
<h1>Meme-ory: Raging on in the Moonlight!</h1>
</header>
<main>
<div id="controls">
<form>
<label for="toptext">Top Text:</label>
<input id="toptext" type="text">
<label for="bottomtext">Bottom Text:</label>
<input id="bottomtext" type="text">
<input id="createMemeButton" type="button" value="Give me Meme!">
</form>
</div>
<div id="imagegallery">
<img class="thumbnail" id="closeenough" src="closeenough.png" alt="close enough">
<img class="thumbnail" id="cutenessoverload" src="cutenessoverload.png" alt="cuteness overload">
<img class="thumbnail" id="deskflip" src="deskflip.png" alt="deskflip">
<img class="thumbnail" id="lol" src="lol.png" alt="LOL">
<img class="thumbnail" id="trollface" src="trollface.png" alt="troll face">
</div>
<div id="memeresult">
<canvas id="imgresult">
</canvas>
</div>
</main>
</body>
</html>
If you try to select an element in a page, you can only do so when it has been created. You cannot select it BEFORE its existence. In this case you try to select a canvas and an image in the HEAD of you page, but these elements are only defined later on in your body.
There are two simple fixes:
Either you move your script code to the end of the page (just before </body>), or you include the code in the $( document ).ready(function() { block, like this:
$(document).ready(function() {
window.onclick = function imgOnClick(e) {
var canvas = document.getElementById("imgresult");
var ctx = canvas.getContext("2d");
var img = document.getElementById("closeenough");
ctx.drawImage(img, 0, 0);
};
});
Both ways ensure that you try to select the elements when they have been created.

Javascript - Changing an image with variables

I'm trying to create a slide show but I'm having some difficulty. I've googled the problem and read loads of pages but I still can't get it to work. I'm doing this all in my header, then the header.php will be included on whichever page. I've tried setting the source to a string containing the location, creating an image before and then setting it to that image's source, and just trying odd things trying to get it to work.
The strange thing is when I call the updateSlider() function, the source of my image is null even though I can see it on the screen, and afterwards when I set it, it says there is a source but the image is the same.
But at the moment I'm just trying to change the image when I click a button and then I'm going to try and make the slide show. Here is the header.php code, you can see some of the different things I've tried in it:
<!DOCTYPE html>
<html>
<head>
<style type="text/css" media="all">#import "./includes/layout.css";</style>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js">
</script>
<script>
var slideImages = new Array("includes/images/mmSlideImage1.png",
"includes/images/mmSlideImage2.png", "includes/images/mmSlideImage3.png");
var slideImage = newImage();
slideImage.src = slideImages[0];
pic = document.createElement("img");
pic.setAttribute("src", "includes/images/mmSlideImage2.png");
pic.setAttribute("alt", "No Image");
var url2 = "includes/images/mmSlideImage2.png";
var img2 = new Image();
img2.src = url2;
function updateSlider() {
console.log(document.getElementById("ht").getAttribute("src"));
document.getElementById("ht").setAttribute("src", img2.src);
console.log(document.getElementById("ht").getAttribute("src"));
}
</script>
</head>
<body>
<img src="includes/images/mmSlideImage1.png" alt="Logo" width="970" height="278" />
<button type="button" onclick="updateSlider()">Update Slider</button>
<div id="nav">
Home
About
Gallery
Programs
</div>
Thank you in advance for any help!
==================================================================================
UPDATED CODE:
<!DOCTYPE html>
<html>
<head>
<style type="text/css" media="all">#import "./includes/layout.css";</style>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"
</script>
<script>
var url2 = "includes/images/mmSlideImage2.png";
function updateSlider() {
console.log(document.getElementById("ht").getAttribute("src"));
$('ht').attr('src', url2);
console.log(document.getElementById("ht").getAttribute("src"));
}
</script>
</head>
<body>
<img src="includes/images/mmSlideImage1.png" alt="Logo" width="970" height="278" />
<button type="button" onclick="updateSlider()">Update Slider</button>
Simple. You're trying to give an anchor a image attribute. Give your img an id and fix it in the Javascript. For example, if you give it an "currentSlideImage" id:
$('#currentSlideImage').attr('src', url2);
BTW, I'd suggest you take a read on Unobstrusive Javascript.
i am not sure why are you using new image when you are just changing src of an image tag.
the easiest way is to use jquery code
$('#imgTagID').attr('src', url2);
or in javascript
document.getElementById("imgTagID").src = url2;
Here you go you were just missing id Tag inside jquery i just tried it with online images
<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js">
</script>
<script>
var url2 = "http://www.thinkstockphotos.com.au/CMS/StaticContent/WhyThinkstockImages/Best_Images.jpg";
function updateSlider() {
//console.log(document.getElementById("ht").getAttribute("src"));
$('#ht').attr('src', url2);
//console.log(document.getElementById("ht").getAttribute("src"));
}
</script>
</head>
<body>
<a href="index.html" class="logo" > <img id="ht" src="http://www.nasa.gov/sites/default/files/images/743348main_Timelapse_Sun_4k.jpg" alt="Logo" width="970" height="278" /></a>
<button type="button" onclick="updateSlider()">Update Slider</button>
</body>
</html>

specify image source in javascript

I was wondering is there a way to only specify the source of an image in javascript. So if I had the following image tag:
<img class="CustomerPict" id="Image" alt="name" src=src style="left: 18px; top: 18.5px;">
And in javascript I want to declare the variable src? Any help would be appreciated!
HTML provides no way to set an attribute value using JavaScript.
You either need to set the src to a default value (possible a 1x1 transparent gif) and then change it with JavaScript later, or to generate the entire img element from JS.
<img class="CustomerPict" id="Image" alt="name" src="1x1.gif" style="left: 18px; top: 18.5px;">
<script>
document.getElementById('Image').src = src;
</script>
or
<script>
var container = document.getElementById('image-container');
var image = document.createElement('img');
image.src = src;
image.id = "Image";
image.className = "CustomerPict";
image.alt = "name";
// You can move these to a style sheet ruleset with a class or id selector
image.style.left = "18px";
image.style.top = "18.5px";
container.appendChild(image);
</script>
document.getElementById('Image').src = 'http://domain.com/picture.png';
<img src="src" id="Image">
document.getElementById('Image').setAttribute('src', 'http://www.gravatar.com/avatar/c9bef77e2d810012d8c96f84b9fc9bc9?s=32&d=identicon&r=PG');
img=document.getElementById("Image");
console.log(img.src);
or the nicer way (in my opinion)
img=document.getElementsByTagName("img");
console.log(img[0].src);
then you can assign img[0].src a value
You can make it a oneliner by using the img-tags onerror attribute:
<img src='not-found.zzz' onerror='this.src=window.src;'>
But make sure that the specified image in window.src (global scope) is correct or the script will loop forever...
<!DOCTYPE html>
<html>
<head>
<meta charset='UTF-8'>
<script type='text/javascript'>
var src = 'my_real_image.png';
</script>
</head>
<body>
<img src='not-found.zzz' onerror='this.src=window.src;'>
</body>
</html>
DEMO: http://jsbin.com/ozimov/1/embed

call on function when all images are clicken on

I want to call a function that opens a new link. I want to do this after all my images have been clicked on. How can i achieve this?
HTML
<!DOCTYPE HTML>
<html>
<head>
<meta charset="windows-1252">
<!--[if lt IE 9]>
<script src="http://html5shim.googlecode.com/svn/trunk/html5.js"> </script>
<![endif]-->
<title>Date med mig - version b
</title>
<script type="text/javascript">
function newWindow()
{
window.location = window.location = "http://www.tv3.se/datemedmig"
}
</script>
</head>
<body>
<h1>Del 2: Date med mig</h1>
<img src="1_c.jpg" id="image1" onclick="this.src='1_o.jpg';" alt="image" />
<img src="2_c.jpg" id="image1" onclick="this.src='2_o.jpg';" alt="image" />
<img src="3_c.jpg" id="image1" onclick="this.src='3_o.jpg';" alt="image" />
<img src="4_c.jpg" id="image1" onclick="this.src='4_o.jpg';" alt="image" />
</body>
</html>
If you are trying to just load a new window as soon as any image is clicked, I think the way that #runfaj said to do it is probably the best, It is my understanding that you want to do it only after ALL images have been clicked on?
If this is the case, here's one option (which is probably not the most efficient)
//Assuming there are 4 images
var hasBeenClicked = [false,false,false,false]
//To be called when each image is clicked
function imageClicked(whichImage){
this.src = "'"+whichImage+"_o.jpg'"
//set this position in the array equal to true
hasBeenClicked[whichImage] = true
// if the array is completely true (every image has been clicked)
// call the newWindow function
if(hasBeenClicked == [true,true,true,true]){
newWindow();
}
}
Then when you create an image:
<img src="1_c.jpg" id="image1" onclick="imageClicked(1);" alt="image" />
you could do it three ways:
jquery:
$('img').click(newWindow);
inline:
<img src=..... onclick="newWindow()" />
regular javascript:
get all the tags with:
var imgs = document.getElementByTagName('img');
then add an event listener to each one (google it for lots of different examples)
Have an onclick function that triggers for each image which sets a new attribute on the image tag. Then run a loop over all images to check that they all have the tag. If so, open new windows. For example:
$('img').click(function() {
$(this).data('was-clicked', true);
var all_clicked = true;
$('img').each(function() {
if($(this).data('was-clicked') != true) {
all_clicked = false;
break;
}
});
if(all_clicked == true) newWindow();
});
Note, this code is not tested and may have syntax/semantic errors. Also, you may not really want the user to click ALL image tags (e.g. banners, backgrounds, etc), so you should modify the jquery selectors to filter only the 'img' tags you're interested in, e.g. $('#my-gallery img')...

get iframe inside div with javascript

Is there a way to do the following in JavaScript?
get a div by a class name,
get the iframe inside the div
and add an attribute (frameborder = 0)
<html>
<body>
<div class="calendar">
<iframe></iframe>
</div>
</body>
</html>
To get a div by class name:
var allDivs = document.getElementsByClassName("calendar");
Assuming there's only one
var calendarDiv = document.getElementsByClassName("calendar")[0];
Get the iFrame inside:
var iFrame = calendarDiv.getElementsByTagName("iframe")[0];
set an attribute:
iFrame.setAttribute("frameborder", "0");
Or, since getElementsByClassName isn't supported in old versions of IE, consider setting the id on the iFrame and simply doing:
document.getElementById("iFrameId").setAttribute("frameborder", "0");
First of all, you need to give your iframe id.
After that, you can get your iframe with the function document.getElementById(""), and than to change it's property.
For example:
<html>
<body>
<div class="calendar">
<iframe id="myIframe"></iframe>
</div>
<script type="text/javascript">
document.getElementById("myIframe").frameborder = 1;
</script>
</body>
</html>

Categories

Resources