Load image with jQuery and append it to the DOM - javascript

I'm trying to load an image from a given link
var imgPath = $(imgLink).attr('href');
and append it to the page, so I can insert it into a given element for an image viewer.
Even though I searched Stackoverflow and the jQuery docs without end, I can't figure it out.
After I load the image, I want to set different values to it, like width, height, etc.
Update:
This is what I got. The problem I'm having is that I can't run jQuery functions on the img element.
function imagePostition(imgLink) {
// Load the image we want to display from the given <a> link
// Load the image path form the link
var imgPath = $(imgLink).attr('href');
// Add image to html
$('<img src="'+ imgPath +'" class="original">').load(function() {
$(imgLink).append(this);
var img = this;
// Resize the image to the window width
// http://stackoverflow.com/questions/1143517/jquery-resizing-image
var maxWidth = $(window).width(); // window width
var maxHeight = $(window).height(); // window height
var imgWidth = img.width; // image width
var imgHeight = img.height; // image height
var ratio = 0; // resize ration
var topPosition = 0; // top image position
var leftPostition = 0; // left image postiton
// calculate image dimension
if (imgWidth > maxWidth) {
ratio = imgHeight / imgWidth;
imgWidth = maxWidth;
imgHeight = (maxWidth * ratio);
}
else if (imgHeight > maxHeight) {
ratio = imgWidth / imgHeight;
imgWidth = (maxHeight * ratio);
imgHeight = maxHeight;
}
// calculate image position
// check if the window is larger than the image
// y position
if(maxHeight > imgHeight) {
topPosition = (maxHeight / 2) - (imgHeight / 2);
}
// x position
if(maxWidth > imgWidth) {
leftPostition = (maxWidth / 2) - (imgWidth / 2);
}
$(imgLink).append(img);
// Set absolute image position
img.css("top", topPosition);
img.css("left", leftPostition);
// Set image width and height
img.attr('width', imgWidth);
img.attr('height', imgHeight);
// Add backdrop
$('body').prepend('<div id="backdrop"></div>');
// Set backdrop size
$("#backdrop").css("width", maxWidth);
$("#backdrop").css("height", maxHeight);
// reveal image
img.animate({opacity: 1}, 100)
img.show()
});
};

$('<img src="'+ imgPath +'">').load(function() {
$(this).width(some).height(some).appendTo('#some_target');
});
If you want to do for several images then:
function loadImage(path, width, height, target) {
$('<img src="'+ path +'">').load(function() {
$(this).width(width).height(height).appendTo(target);
});
}
Use:
loadImage(imgPath, 800, 800, '#some_target');

Here is the code I use when I want to preload images before appending them to the page.
It is also important to check if the image is already loaded from the cache (for IE).
//create image to preload:
var imgPreload = new Image();
$(imgPreload).attr({
src: photoUrl
});
//check if the image is already loaded (cached):
if (imgPreload.complete || imgPreload.readyState === 4) {
//image loaded:
//your code here to insert image into page
} else {
//go fetch the image:
$(imgPreload).load(function (response, status, xhr) {
if (status == 'error') {
//image could not be loaded:
} else {
//image loaded:
//your code here to insert image into page
}
});
}

var img = new Image();
$(img).load(function(){
$('.container').append($(this));
}).attr({
src: someRemoteImage
}).error(function(){
//do something if image cannot load
});

after you get the image path, try either of following ways
(as you need to set more attr than just the src)
build the html and replace to the target region
$('#target_div').html('<img src="'+ imgPaht +'" width=100 height=100 alt="Hello Image" />');
you may need to add some delay if changing the "SRC" attr
setTimeout(function(){///this function fire after 1ms delay
$('#target_img_tag_id').attr('src',imgPaht);
}, 1);

I imagine that you define your image something like this:
<img id="image_portrait" src="" alt="chef etat" width="120" height="135" />
You can simply load/update image for this tag and chage/set atts (width,height):
var imagelink;
var height;
var width;
$("#image_portrait").attr("src", imagelink);
$("#image_portrait").attr("width", width);
$("#image_portrait").attr("height", height);

With jQuery 3.x use something like:
$('<img src="'+ imgPath +'">').on('load', function() {
$(this).width(some).height(some).appendTo('#some_target');
});

Related

Resizing image preview not working

Working JSFiddle before attempting to implement: http://jsfiddle.net/qa9m7t33/
After attempting to implement: http://jsfiddle.net/z1k538sm/
I found how to resize an image however I believe this was not an example for being it prior upload and I am pretty new to this. What I believe is wrong is the variable;'
var width = e.target.result.width(); // Current image width
var height = e.target.result.height(); // Current image height
I am also having the problem with centering my text in the upload field.
Updated Fiddle: http://jsfiddle.net/m5jLf259/
Not exactly a Js answer to this but adding a line-height CSS to the element
#file {
line-height: 37px;
}
will get the job done, I guess if you want it to be jQuery you could do
$('#file').css('line-height',$('#file').height() + 'px');
As for the first part of your problem I couldn't make out a question, sorry.
Edit:
for the first part try this:
var wrapper = $('<div/>').css({height:0,width:0,'overflow':'hidden'});
var fileInput = $(':file').wrap(wrapper);
fileInput.change(function(){
readURL(this);
})
$('#file').click(function(){
fileInput.click();
}).show();
function readURL(input) {
$('#blah').hide();
if (input.files && input.files[0]) {
var goUpload = true;
var uploadFile = input.files[0];
if (!(/\.(gif|jpg|jpeg|tiff|png)$/i).test(uploadFile.name)) {
$('#file').effect( "shake" );
$('#file').text('You must select an image file only');
setTimeout(function() { $('#file').text('Choose file');},5000);
goUpload = false;
}
if (uploadFile.size > 2000000) { // 2mb
//common.notifyError('Please upload a smaller image, max size is 2 MB');
$('#file').text('Please upload a smaller image, max size is 2 MB');
setTimeout(function() { $('#file').text('Choose file');},5000);
goUpload = false;
}
if (goUpload) {
$('#file').text("Uploading "+uploadFile.name);
var reader = new FileReader();
reader.onload = function (e) {
var img = new Image;
img.onload = function() {
var maxWidth = 100; // Max width for the image
var maxHeight = 100; // Max height for the image
var ratio = 0; // Used for aspect ratio
var width = this.width; // Current image width
var height = this.height; // Current image height
// Check if the current width is larger than the max
if (width > maxWidth) {
ratio = maxWidth / width; // get ratio for scaling image
$('#blah').css("width", maxWidth); // Set new width
$('#blah').css("height", height * ratio); // Scale height based on ratio
height = height * ratio; // Reset height to match scaled image
}
// Check if current height is larger than max
if (height > maxHeight) {
ratio = maxHeight / height; // get ratio for scaling image
$('#blah').css("height", maxHeight); // Set new height
$('#blah').css("width", width * ratio); // Scale width based on ratio
width = width * ratio; // Reset width to match scaled image
}
$('#blah').attr('src', this.src).show();
$('#file').text(uploadFile.name);
};
img.src = reader.result;
}
reader.readAsDataURL(uploadFile);
}
}
}
You shouldn't have the part where it says:
47 var width = uploadFile.width(); // Current image width
48 var height = uploadFile.height(); // Current image height
twice because you're just undoing your work from the previous IF.
Also it seems the FileReader() is unable to get the image size properties so instead have FileReader, create an image Object, and then make the image Object's onload do all the work.

Resize image before loading - jquery

I'm using this plugin to create image zoom and gallery, yet I want to scale all images to fit with the container (using ratio algorithm).
Here is ratio function :
function scaleSize(maxW, maxH, currW, currH){
var ratio = currH / currW;
if(currW >= maxW && ratio <= 1){
currW = maxW;
currH = currW * ratio;
} else if(currH >= maxH){
currH = maxH;
currW = currH / ratio;
}
return [currW, currH];
}
And this is how the gallery load images :
var img = $('<img>').load(function(){
img.appendTo(a);
image_container.html(a);
}).attr('src', src).addClass(opts.big_image_class);
What I've tried :
var newSize = scaleSize(300, 320, $(".simpleLens-big-image").width(), $(".simpleLens-big-image").height());
var img = $('<img>').load(function(){
img.appendTo(a);
image_container.html(a);
}).attr('src', src).addClass(opts.big_image_class).width(newSize[0]).height(newSize[1]);
But scaleSize is not working properly since the current width and height is not yet defined (image not yet exist in dom).
Thanks for any pointers.
I took a look into plugin code and think you call your scaleSize() too early. An image with class simpleLens-big-image exists first after var img is set up and addClass() is done.
Try following:
var img = $('<img>').load(function(){
img.appendTo(a);
image_container.html(a);
}).attr('src', src).addClass(opts.big_image_class);
// at this point img should contain $(".simpleLens-big-image") so we can refer to img
var newSize = scaleSize(300, 320, img[0].naturalWidth, img[0].naturalHeight());
img.width(newSize[0]).height(newSize[1]);
Try something like this and call the onload method. This will make sure that the image is loaded to the DOM before you resize
var img = $('<img>');
img.src = src ;
img.onload = function() {
// Run onload code.
} ;

how to direct download button to url with showing the image

i have this code. and i want when i press download image that it will show the filtered image in my designed webpage. someone can help me how can i do this?
i know i have to change something here in the url. but its dont working and i dont really know why:
var url = canvas.toDataURL("image/png;base64;"); downloadImage.attr('href', url);
please help me.
$(function() {
/*
In this code, we are going to do the following:
1. Accept an image on drag and drop
2. Create a new canvas element (original), with a max size
of 500x500px (customizable) and keep it in memory
3. Listen for clicks on the filters. When one is selected:
3.1 Create a clone of the original canvas
3.2 Remove any canvas elements currently on the page
3.3 Append the clone to the #photo div
3.4 If the selected filter is different from the "Normal"
one, call the Caman library. Otherwise do nothing.
3.5 Mark the selected filter with the "active" class
4. Trigger the "Normal" filter
*/
var maxWidth = 500,
maxHeight = 500,
photo = $('#photo'),
originalCanvas = null,
filters = $('#filters li a'),
filterContainer = $('#filterContainer');
// Use the fileReader plugin to listen for
// file drag and drop on the photo div:
photo.fileReaderJS({
on:{
load: function(e, file){
// An image has been dropped.
var img = $('<img>').appendTo(photo),
imgWidth, newWidth,
imgHeight, newHeight,
ratio;
// Remove canvas elements left on the page
// from previous image drag/drops.
photo.find('canvas').remove();
filters.removeClass('active');
// When the image is loaded successfully,
// we can find out its width/height:
img.load(function() {
imgWidth = this.width;
imgHeight = this.height;
// Calculate the new image dimensions, so they fit
// inside the maxWidth x maxHeight bounding box
if (imgWidth >= maxWidth || imgHeight >= maxHeight) {
// The image is too large,
// resize it to fit a 500x500 square!
if (imgWidth > imgHeight) {
// Wide
ratio = imgWidth / maxWidth;
newWidth = maxWidth;
newHeight = imgHeight / ratio;
} else {
// Tall or square
ratio = imgHeight / maxHeight;
newHeight = maxHeight;
newWidth = imgWidth / ratio;
}
} else {
newHeight = imgHeight;
newWidth = imgWidth;
}
// Create the original canvas.
originalCanvas = $('<canvas>');
var originalContext = originalCanvas[0].getContext('2d');
// Set the attributes for centering the canvas
originalCanvas.attr({
width: newWidth,
height: newHeight
}).css({
marginTop: -newHeight/2,
marginLeft: -newWidth/2
});
// Draw the dropped image to the canvas
// with the new dimensions
originalContext.drawImage(this, 0, 0, newWidth, newHeight);
// We don't need this any more
img.remove();
filterContainer.fadeIn();
// Trigger the default "normal" filter
filters.first().click();
});
// Set the src of the img, which will
// trigger the load event when done:
img.attr('src', e.target.result);
},
beforestart: function(file){
// Accept only images.
// Returning false will reject the file.
return /^image/.test(file.type);
}
}
});
// Listen for clicks on the filters
filters.click(function(e){
e.preventDefault();
var f = $(this);
if(f.is('.active')){
// Apply filters only once
return false;
}
filters.removeClass('active');
f.addClass('active');
// Clone the canvas
var clone = originalCanvas.clone();
// Clone the image stored in the canvas as well
clone[0].getContext('2d').drawImage(originalCanvas[0],0,0);
// Add the clone to the page and trigger
// the Caman library on it
photo.find('canvas').remove().end().append(clone);
var effect = $.trim(f[0].id);
Caman(clone[0], function () {
// If such an effect exists, use it:
if( effect in this){
this[effect]();
this.render();
// Show the download button
showDownload(clone[0]);
}
else{
hideDownload();
}
});
});
// Use the mousewheel plugin to scroll
// scroll the div more intuitively
filterContainer.find('ul').on('mousewheel',function(e, delta){
this.scrollLeft -= (delta * 50);
e.preventDefault();
});
var downloadImage = $('a.downloadImage');
function showDownload(canvas){
downloadImage.off('click').click(function(){
// When the download link is clicked, get the
// DataURL of the image and set it as href:
var url = canvas.toDataURL("image/png;base64;");
downloadImage.attr('href', url);
}).fadeIn();
}
function hideDownload(){
downloadImage.fadeOut();
}
});
You can try this:
var downloadImage = $('a.downloadImage');
var url = canvas.toDataURL("image/png;base64;");
downloadImage.attr('href', url);

Javascript Resize Image not working

I have JS which resize the width and height of Image which is working fine if I used Alert before assigning the actual image src to the image object and if I omit the alertbox, it is not working. Please suggest me how to fix it.
`
<html>
<head>
<script type="text/javascript" language="javascript">
function resize_image_height_weight(id, hgt, wdth)
{
//alert(id);
Obj=document.getElementById(id);
myImage = new Image();
myImage.src = Obj.src;
var heights = myImage.height;
var widths = myImage.width;
// alert("Height=>" + heights + " Width=> " + widths);
if(heights > hgt || widths > wdth)
{
if(heights > widths)
{
var temp = heights/hgt;
var new_width = widths / temp;
new_width = parseInt(new_width);
heights = hgt;
widths = new_width;
}
else
{
var temp = widths/wdth;
var new_height = heights / temp;
new_height = parseInt(new_height);
heights = new_height;
widths = wdth;
}
}
Obj.height = heights;
Obj.width = widths;
}
</script>
</head>
<body>
<div>
<center>
<img src="http://www.google.co.in/intl/en_com/images/srpr/logo1w.png" id="i" alt="Google logo" height="150" width="150">
<script type="text/javascript">
document.images[document.images.length-1].onload = resize_image_height_weight("i",150,150);
</script>
</center>
</div>
</body>
</html>`
When you set the .src on an image, you have to wait until the image is successfully loaded until you can read it's height and width. There is an onload event handler that will tell you when the image is loaded.
Here's a place in your code where this issue could occur:
Obj=document.getElementById(id);
myImage = new Image();
myImage.src = Obj.src;
var heights = myImage.height;
var widths = myImage.width;
In this case, since the image was already elsewhere in the document, you should just read the height and width off the existing element rather than the new element.
Be very careful when testing because if the image is in your browser cache, it may load immediately, but when it's not in your cache, it takes some time to load and won't be available immediately.
Putting an alert at the right place in your script can allow the image to load before the script proceeds which could explain why it works with the alert.
As RobG mentions, your onload handler is also faulty (needs to be a function, not the returned result of a function).
Here's a simpler function to scale an image to fit the bounds. This uses a trick that you only need to set one size (height or width on the image) and the other will be scaled by the browser to preserve the aspect ratio.
function resizeImage(id, maxHeight, maxWidth) {
// assumes the image is already loaded
// assume no height and width is being forced on it yet
var img = document.getElementById(id);
var height = img.height || 0;
var width = img.width || 0;
if (height > maxHeight || width > maxWidth) {
var aspect = height / width;
var maxAspect = maxHeight / maxWidth;
if (aspect > maxAspect) {
img.style.height = maxHeight + "px";
} else {
img.style.width = maxWidth + "px";
}
}
}
You can see it in action here: http://jsfiddle.net/jfriend00/BeJg4/.
In the function assigned to onload:
> document.images[document.images.length-1].onload =
> resize_image_height_weight("i",150,150);
you are assigning the result of calling resize_image_height_weight which throws an error in IE. Set it to a function instead:
document.images[document.images.length-1].onload = function() {
resize_image_height_weight("i",150,150);
};

Getting image width on image load fails on IE

I have a image resizer function that resize images proportional. On every image load a call this function with image and resize if its width or height is bigger than my max width and max height. I can get img.width and img.height in FF Chrome Opera Safari but IE fails. How can i handle this?
Let me explain with a piece of code.
<img src="images/img01.png" onload="window.onImageLoad(this, 120, 120)" />
function onImageLoad(img, maxWidth, maxHeight) {
var width = img.width; // Problem is in here
var height = img.height // Problem is in here
}
In my highligted lines img.width don't work on IE series.
Any suggestion?
Thanks.
Don't use width and height. Use naturalWidth and naturalHeight instead. These provide the image unscaled pixel dimensions from the image file and will work across browsers.
Man, I was looking for this for 2 days. Thanks.
I'm using jQuery, but it doesnt matter. Problem is related to javascript in IE.
My previous code:
var parentItem = $('<div/>')
.hide(); // sets display to 'none'
var childImage = $('<img/>')
.attr("src", src)
.appendTo(parentItem) // sets parent to image
.load(function(){
alert(this.width); // at this point image is not displayed, because parents display parameter is set to 'none' - IE gives you value '0'
});
This is working in FF, Opera and Safari but no IE. I was getting '0' in IE.
Workaround for me:
var parentItem = $('<div/>')
.hide();
var childImage = $('<img/>')
.attr("src", src)
.load(function(){
alert(this.width); // at this point image css display is NOT 'none' - IE gives you correct value
childImage.appendTo(parentItem); // sets parent to image
});
This is how I solved it (because it's the only js on the site I didn't want to use a library).
var imageElement = document.createElement('img');
imageElement.src = el.href; // taken from a link cuz I want it to work even with no script
imageElement.style.display = 'none';
var imageLoader = new Image();
imageLoader.src = el.href;
imageLoader.onload = function() {
loaderElement.parentElement.removeChild(loaderElement);
imageElement.style.position = 'absolute';
imageElement.style.top = '50%';
imageElement.style.left = '50%';
// here using the imageLoaders size instead of the imageElement..
imageElement.style.marginTop = '-' + (parseInt(imageLoader.height) / 2) + 'px';
imageElement.style.marginLeft = '-' + (parseInt(imageLoader.width) / 2) + 'px';
imageElement.style.display = 'block';
}
It's because IE can't calculate width and height of display: none images. Use visibility: hidden instead.
Try
function onImageLoad(img, maxWidth, maxHeight) {
var width = img.width; // Problem is in here
var height = img.height // Problem is in here
if (height==0 && img.complete){
setTimeOut(function(){onImageLoad(img, maxWidth, maxHeight);},50);
}
}
var screenW = screen.width;
var screenH = screen.height;
//alert( screenW );
function checkFotoWidth( img, maxw )
{
if( maxw==undefined)
maxw = 200;
var imgW = GetImageWidth(img.src);
var imgH = GetImageHeight(img.src);
//alert(GetImageWidth(img.src).toString()); // img.width); // objToString(img));
if (imgW > maxw || (img.style.cursor == "hand" && imgW == maxw))
{
if (imgW > screenW) winW = screenW;
else winW = imgW;
if (imgH > screenH) winH = screenH;
else winH = imgH;
img.width=maxw;
img.style.cursor = "pointer";
img.WinW = winW;
img.WinH = winH;
//alert("winW : " + img.WinW);
img.onclick = function() { openCenteredWindow("Dialogs/ZoomWin.aspx?img=" + this.src, this.WinW, this.WinH, '', 'resizable=1'); }
img.alt = "Klik voor een uitvergroting :: click to enlarge :: klicken Sie um das Bild zu vergrössern";
//alert("adding onclick);
}
}
function GetImageWidth(imgSrc)
{
var img = new Image();
img.src = imgSrc;
return img.width;
}
function GetImageHeight(imgSrc)
{
var img = new Image();
img.src = imgSrc;
return img.height;
}
I'd try this:
function onImageLoad(img, maxWidth, maxHeight) {
var width, height;
if ('currentStyle' in img) {
width = img.currentStyle.width;
height = img.currentStyle.height;
}
else {
width = img.width;
height = img.height;
}
// whatever
}
edit — and apparently if I were to try that I'd learn it doesn't work :-) OK, well "width" and "height" definitely seem to be attributes of <img> elements as far as IE is concerned. Maybe the problem is that the "load" event is firing for the element at the wrong time. To check whether that's the case, I would then try this:
function onImageLoad(img, maxWidth, maxHeight) {
var width, height;
var i = new Image();
i.onload = function() {
width = i.width; height = i.height;
// ... stuff you want to do ...
};
i.src = img.href;
}
getDisplay().getImage().setUrl(imgURL);
final Image img = new Image(imgURL);
int w=img.getWidth();
int h=img.getHeight();

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