How can I rotate a base64 image in AngularJS - angularjs

I have a json source that contains base64 images, and I would like to display them all in portrait. I think I need to build an array of Image objects, and rotate them as I build the array, but I'm not sure how to display the image objects in the view.
This is the array I've built
angular.forEach($scope.trayDetails.tray_images, function(trayImage) {
var myBase64 = "data:image/png;base64,"+trayImage.data;
var img = new Image();
img.src = myBase64;
if (img.width>img.height ) {
$(img).css({
'transform': "rotate(90deg)"
});
}
$scope.savedPictures.push(img);
});
But now I'm not sure what to do with the array, I tried these 2 methods with no luck
<li ng-repeat="savedPicture in savedPictures" class="photo">
{{savedPicture}}
</li>
<li ng-repeat="savedPicture in savedPictures" class="photo">
<img ng-src="{{savedPicture}}" />
</li>

The solution is easier than you think:
angular.forEach($scope.trayDetails.tray_images, function(trayImage) {
var myBase64 = "data:image/png;base64,"+trayImage.data;
var img = new Image();
img.src = myBase64;
img.isRotated = img.width > img.height; //Use css class to rotate
$scope.savedPictures.push(img);
});
Then add the img into html,:
<li ng-repeat="savedPicture in savedPictures" class="photo">
<img ng-class="{rotateImg: savedPicture.isRotated}" ng-src="{{savedPicture.src}}" />
</li>
The img tags will have rotateImg class if its width is greater than its height. The css for rotateImg class is:
.rotateImg : { transform: rotate(90deg); }

Related

How to pass a variable to css in AngularJS

I'm trying to make a virtual scroll and whenever the user scrolls down I need to add a negative top equal to the container height to each row. But of course this top property can vary depending of some factors like the user's screen resolution or browser window size.
So far this is what I got:
<div class="container" id="my-container">
<!--If it has the class row-scrolled the top property is applied-->
<div ng-repeat="(row) in virtualCollection"
ng-class="{'row-scrolled': controller.isScrolled}">
<!-- row properties -->
</div>
</div>
I have also thought about the idea of using ng-style but would override any style from my .css file.
Is there anyway to get the size/property of a DOM element...
// controller
var containerHeight = angular.element('#my-container')[0].clientHeight;
var cssProperty = '-' + containerHeight + 'px';
And then use it in an css?
// css
.row-scrolled {
top: cssProperty;
}
You can't pass variables from javascript to CSS since CSS is not a programming language but a style sheet language.
What you can do is manipulating specific elements with javascript.
Based on your code here is an example:
// controller
var containerHeight = angular.element('#my-container')[0].clientHeight;
var cssProperty = '-' + containerHeight + 'px';
var $$rowScrolled = document.querySelectorAll(".row-scrolled");
if ($$rowScrolled && $$rowScrolled.length > 0) {
for (var i = 0; i < $$rowScrolled.length; i++) {
var $rowScrolled = $$rowScrolled[i];
$rowScrolled.style.top = cssProperty;
}
}
With jQuery:
// controller
var containerHeight = angular.element('#my-container')[0].clientHeight;
var cssProperty = '-' + containerHeight + 'px';
var $rowScrolled = $(".row-scrolled");
if ($rowScrolled && $rowScrolled.length > 0) {
$rowScrolled.css("top", cssProperty);
}
You can not pass a variable to the CSS.
What you can do though is add the property directly using the ng-style tag:
<div class="container" id="my-container">
<!--If it has the class row-scrolled the top property is applied-->
<div ng-repeat="(row) in virtualCollection"
ng-style="{'top': controller.cssProperty}">
<!-- row properties -->
</div>

how to replace image source in react?

Could you please tell me how to replace image source in react? .I am setting a src url to my img tag.
If image is not present on server I want to replace src url to this one http://punemirror.indiatimes.com/photo/55813567.cms
if image is present on server then it fine .if not then I need to change source url to "http://punemirror.indiatimes.com/photo/55813567.cms
"
here is my code
https://codesandbox.io/s/KOrGKp3B8
I try like that
imageExists(url, callback) {
var img = new Image();
img.onload = function () {
callback(true);
};
img.onerror = function () {
callback(false);
};
img.src = url;
}
renderList() {
const lis = this.items.map((item, key) => {
var src = "http://mumbaimirror.indiatimes.com/photo/" + item.id + ".cms";
const alt = "http://punemirror.indiatimes.com/photo/55813567.cms";
return (
<li key={key}>
<a><img src={src}/><span>{item.hl}</span></a>
</li>
)
})
return (
<ul>
{lis}
</ul>
)
}
render() {
return (
<div className="list">
{this.renderList()}
</div>
)
}
}
Check if your image exists, use this method and then in your component class :
componentWillMount() {
var url = "http://mumbaimirror.indiatimes.com/photo/" + item.id + ".cms";
const alt = "http://punemirror.indiatimes.com/photo/55813567.cms";
var src = this.imageExists(url) ? url : alt;
this.setState({ src });
}
// added from the mentioned post
function imageExists(image_url){
var http = new XMLHttpRequest();
http.open('HEAD', image_url, false);
http.send();
return http.status != 404;
}
render() {
var src = this.state.src;
...
}
You can use object for this.
<object data={src} type="image/png">
<img src="http://punemirror.indiatimes.com/photo/55813567.cms" />
</object>
On component render, you need to check server-side for all present files, and return an array of all file ids you got on the server.
When you get that array of existing files, let's call it allFileIds, you just need to do :
<li key={key}>
<a><img src={allFileIds.indexOf(item.id) !== -1 ? src : alt}/><span>{item.hl}</span></a>
</li>
This will check if the required id was found on the server (it checks if the item.id value exists in the array of file ids that your server returned), and if not, render the alt property instead of the src. I hope that was clear!
First put your image collection in state instead of field.
I assume each image in your images collection contains at least one field: url. You can check your images (this.items) for existence in componentDidMount/componentWillReceiveProps. Note that your imageExists method is async - therefore you cant use it during rendering. Based on the check you can set img.src to be either undefined/null or valid URL.
Then in render check image.url and if it is missing - use default one.

Convert SVG to image in PNG

i am converting angular nvd3 chart to svg using html2canvas and canvg plugings but when i convert pie chart to png then i looks same as chart but when i convert line chart or area chart then its background goes to black and some circle drown on image.
My code is
var svgElements = $("#container").find('svg');
//replace all svgs with a temp canvas
svgElements.each(function () {
var canvas, xml;
// canvg doesn't cope very well with em font sizes so find the calculated size in pixels and replace it in the element.
$.each($(this).find('[style*=em]'), function (index, el) {
$(this).css('font-size', getStyle(el, 'font-size'));
});
canvas = document.createElement("canvas");
canvas.className = "screenShotTempCanvas";
//convert SVG into a XML string
xml = (new XMLSerializer()).serializeToString(this);
// Removing the name space as IE throws an error
xml = xml.replace(/xmlns=\"http:\/\/www\.w3\.org\/2000\/svg\"/, '');
//draw the SVG onto a canvas
canvg(canvas, xml);
$(canvas).insertAfter(this);
//hide the SVG element
////this.className = "tempHide";
$(this).attr('class', 'tempHide');
$(this).hide();
});
html2canvas($("#container"), {
onrendered: function (canvas) {
var a = document.createElement("a");
a.download = "Dashboard.png";
a.href = canvas.toDataURL("image/png");
a.click();
var imgData = canvas.toDataURL('image/png');
var doc = new jsPDF('p', 'mm','a4');
var width = doc.internal.pageSize.width;
var height = doc.internal.pageSize.height;
doc.addImage(imgData, 'PNG', 0, 0, width, height);
doc.save('Dashboard.pdf');
}
});
$("#container").find('.screenShotTempCanvas').remove();
$("#container").find('.tempHide').show().removeClass('tempHide');
Help me guys.
Thanks In Advance
Your svg elements are being styled by the external stylesheet nv.d3.min.css .
canvg seems unable to access external style sheets, so you need to append it directly in your svg node.
To do so, if your style sheet is hosted on the same domain as your scripts, you can do something like :
var sheets = document.styleSheets;
var styleStr = '';
Array.prototype.forEach.call(sheets, function(sheet){
try{ // we need a try-catch block for external stylesheets that could be there...
styleStr += Array.prototype.reduce.call(sheet.cssRules, function(a, b){
return a + b.cssText; // just concatenate all our cssRules' text
}, "");
}
catch(e){console.log(e);}
});
// create our svg nodes that will hold all these rules
var defs = document.createElementNS('http://www.w3.org/2000/svg', 'defs');
var style = document.createElementNS('http://www.w3.org/2000/svg', 'style');
style.innerHTML = styleStr;
defs.appendChild(style);
// now append it in your svg node
thesvg[0].insertBefore(defs, thesvg[0].firstElementChild);
So now you can call the XMLSerializer, and canvg will be happy.
(note that this is not only a canvg limitation, the same applies for every way to draw an svg on a canvas).
Forked plunkr, where I copied the nv.d3.min.css's content to a same-origin style.css.
Very late to the conversation but I just wanted to add that the solution as described by Kaiido, put very simply, is to embed the styles into the SVG document directly.
In order to do this, you manipulate the DOM to make the SVG element look like this:
<svg xmlns="http://www.w3.org/2000/svg" width="200" height="100" version="1.1">
<defs>
<style>
.rectangleStyle{
width:200px;
height:100px;
stroke:black;
stroke-width: 6;
fill: green;
}
</style>
</defs>
<rect class="rectangleStyle"/>
</svg>

How to test three.js tutorial in the View of CakePHP?

I get stuck when try to insert a demo of three.js tutorial into the view of CakePHP,
This demo (creating a scene): enter link description here
Has anybody try it like that ?
Thanks for reading . I hope you share your experiments.
Detail my problems:
I create webgl_test.js and put it into ...webroot/js/, and also put the three.min.js into webroot/js/
//------------- CREATING THE SCENE-----------------------
/* To actually be able to display anything with Three.js, we need three things:
1. A Scene
2. A Camera
3. A Renderer so we can render the scene with the camera
*/
var main=function() {
var CANVAS=document.getElementById("your_canvas");
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera (75, window.innerWidth/window.innerHeight, 0.1, 1000);
var renderer = new THREE.WebGLRenderer({
antialias : true,
canvas : CANVAS
});
renderer.setSize(window.innerWidth, window.innerHeight);
//document.body.appendChild(renderer.domElement); //we add the renderer element to our HTML document
var geometry = new THREE.BoxGeometry (2,1,1);
var material = new THREE.MeshBasicMaterial ({color: 0x00ffff});
var cube = new THREE.Mesh (geometry, material);
scene.add(cube);
camera.position.z = 5;
//-------------RENDERING THE SCENE------------------------
function render(){
requestAnimationFrame(render);
cube.rotation.x += 0.01;
cube.rotation.y += 0.01;
renderer.render(scene, camera);
}
render();
};
In the header of default.ctp, I call script's library like that
<head>
<script type="text/javascript" src="/js/webgl_test.js"></script>
<script type="text/javascript" src="/js/three.min.js"></script>
</head>
Last step, I write some lines to show <canvas> element as below:
<div>
<ul>
<li onload='main()'>
<canvas id='your_canvas'style='position: absolute;'></canvas>
</li>
</ul>
</div>
Then, It show nothing :((

AngularJS directive to create a thumbnail

I've just started learning AngularJS and I'm approaching directives. I'd need to create a directive named f.e. "thumbnail" which takes as input a "src" (the image) and create a thumbnail of it.
So far I've coded the javascript function to create the thumbnail which does its job correctly:
function readURL(input) {
var imageSize = 50;
if (input.files && input.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
var blah = $('#myimage');
blah.attr('src', e.target.result);
var height = blah.height();
var width = blah.width();
if (height < imageSize && width < imageSize) {
if (width > height) {
blah.width(imageSize);
}
else {
blah.height(imageSize)
}
}
};
reader.readAsDataURL(input.files[0]);
}
}
</script>
<body onload="readURL(this);">
<img id="myimage" src="../picture.gif" width="50" alt="your image" />
However I have not been able to find a simple example which produces (in AngularJS) an Element, based on a JS function. Any help ?
Thanks!
It depends on what you want to achieve. If your purpose of creating a thumbnail at client-side is to:
Upload in a smaller size in a web application: perhaps you can make use of a library like http://www.plupload.com.
Display only: you should just use CSS resizing with width and height properties.
<img src="/original/320x320.jpg" style="width: 100px; height: 100px">
Reading/storing in an Ionic/PhoneGap app: try make use of angular-thumbnail (disclaimer: I wrote it)
Doing image manipulation of this kind on the client side is not a very good idea , because, as of now there isn't a good support for Filereader in IE.
You can delegate this either to server(you will find lot of node module for image manipulation) or you can use external services like cloudinay

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