我想在画布上加载和显示多个图像。图像源保存在一个数组中:
var sources = {"../src/img/IMG_1284.JPG", "../src/img/IMG_1285.JPG", "../src/img/IMG_1286.JPG", "../src/img/IMG_1287.JPG", "../src/img/IMG_1288.JPG"}
我找到了这个教程:http://www.html5canvastutorials.com/tutorials/html5-canvas-image-loader
但我不知道如何将此代码改编为我的sources数组。 另外,我想设置每个可拖动的图像,但我认为使用context.drawImage(..)是不可能的。
希望我的问题是可以理解的。谢谢你的帮助...
答案 0 :(得分:4)
我看到你用KineticJS标记了你的问题。
KineticJS通过跟踪您的图像使您的任务变得简单,并允许您的用户拖动它们。
简单如下:
这是代码和演示:http://jsfiddle.net/m1erickson/3es4Z/
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Prototype</title>
<script type="text/javascript" src="http://code.jquery.com/jquery.min.js"></script>
<script src="http://d3lp1msu2r81bx.cloudfront.net/kjs/js/lib/kinetic-v4.7.2.min.js"></script>
<style>
body{padding:20px;}
#container{
border:solid 1px #ccc;
margin-top: 10px;
width:350px;
height:350px;
}
</style>
<script>
$(function(){
// create the Kinetic stage and layer
var stage = new Kinetic.Stage({
container: 'container',
width: 350,
height: 350
});
var layer = new Kinetic.Layer();
stage.add(layer);
// put the paths to your images in imageURLs
var imageURLs=[];
imageURLs.push("https://dl.dropboxusercontent.com/u/139992952/stackoverflow/house204-1.jpg");
imageURLs.push("https://dl.dropboxusercontent.com/u/139992952/stackoverflow/house204-2.jpg");
imageURLs.push("https://dl.dropboxusercontent.com/u/139992952/stackoverflow/house204-3.jpg");
var imagesOK=0;
var imgs=[];
// fully load every image, then call the start function
loadAllImages(start);
function loadAllImages(callback){
for (var i=0; i<imageURLs.length; i++) {
var img = new Image();
imgs.push(img);
img.onload = function(){
imagesOK++;
if (imagesOK>=imageURLs.length ) {
callback();
}
};
img.onerror=function(){alert("image load failed");}
img.crossOrigin="anonymous";
img.src = imageURLs[i];
}
}
function start(){
// the imgs[] array holds fully loaded images
// the imgs[] are in the same order as imageURLs[]
// make each image into a draggable Kinetic.Image
for(var i=0;i<imgs.length;i++){
var img=new Kinetic.Image({
x:i*75+15,
y:i*75+15,
width:60,
height:60,
image:imgs[i],
draggable:true
});
layer.add(img);
}
layer.draw();
}
}); // end $(function(){});
</script>
</head>
<body>
<button id="myButton">Button</button>
<div id="container"></div>
</body>
</html>