create-gojs-kit
Version:
A CLI for downloading GoJS samples, extensions, and docs
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HTML
<html lang="en">
<head>
<meta charset="utf-8"/>
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no, viewport-fit=cover"/>
<meta name="description" content="Minimal, showing image Blob creation and download with Diagram.makeImageData." />
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<title>
Minimal Image Download Using MakeImageData and Blobs | GoJS Diagramming Library
</title>
</head>
<body>
<!-- This top nav is not part of the sample code -->
<nav id="navTop" class=" w-full h-[var(--topnav-h)] z-30 bg-white border-b border-b-gray-200">
<div class="max-w-screen-xl mx-auto flex flex-wrap items-start justify-between px-4">
<a class="text-white bg-nwoods-primary font-bold !leading-[calc(var(--topnav-h)_-_1px)] my-0 px-2 text-4xl lg:text-5xl logo"
href="../">
GoJS
</a>
<div class="relative">
<button id="topnavButton" class="h-[calc(var(--topnav-h)_-_1px)] px-2 m-0 text-gray-900 bg-inherit shadow-none md:hidden hover:!bg-inherit hover:!text-nwoods-accent hover:!shadow-none" aria-label="Navigation">
<svg class="h-7 w-7 block" aria-hidden="true" fill="none" stroke="currentColor" stroke-width="2" viewBox="0 0 24 24">
<path d="M3.75 6.75h16.5M3.75 12h16.5m-16.5 5.25h16.5" stroke-linecap="round" stroke-linejoin="round"/>
</svg>
</button>
<div id="topnavList" class="hidden md:block">
<div class="absolute right-0 z-30 flex flex-col items-end rounded border border-gray-200 p-4 pl-12 shadow bg-white text-gray-900 font-semibold
md:flex-row md:space-x-4 md:items-start md:border-0 md:p-0 md:shadow-none md:bg-inherit">
<a href="../learn/">Learn</a>
<a href="../samples/">Samples</a>
<a href="../intro/">Intro</a>
<a href="../api/">API</a>
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target="_blank" rel="noopener" onclick="getOutboundLink('https://nwoods.com/contact.html', 'contact');">Contact</a>
<a id="tb" href="https://nwoods.com/sales/index.html"
target="_blank" rel="noopener" onclick="getOutboundLink('https://nwoods.com/sales/index.html', 'buy');">Buy</a>
</div>
</div>
</div>
</div>
</nav>
<script>
window.addEventListener("DOMContentLoaded", function () {
// topnav
var topButton = document.getElementById("topnavButton");
var topnavList = document.getElementById("topnavList");
if (topButton && topnavList) {
topButton.addEventListener("click", function (e) {
topnavList
.classList
.toggle("hidden");
e.stopPropagation();
});
document.addEventListener("click", function (e) {
// if the clicked element isn't the list, close the list
if (!topnavList.classList.contains("hidden") && !e.target.closest("#topnavList")) {
topButton.click();
}
});
// set active <a> element
var url = window
.location
.href
.toLowerCase();
var aTags = topnavList.getElementsByTagName('a');
for (var i = 0; i < aTags.length; i++) {
var lowerhref = aTags[i]
.href
.toLowerCase();
if (lowerhref.endsWith('.html'))
lowerhref = lowerhref.slice(0, -5);
if (url.startsWith(lowerhref)) {
aTags[i]
.classList
.add('active');
break;
}
}
}
});
</script>
<div class="flex flex-col prose">
<div class="w-full max-w-screen-xl mx-auto">
<!-- * * * * * * * * * * * * * -->
<!-- Start of GoJS sample code -->
<script src="https://cdn.jsdelivr.net/npm/gojs@3.1.0"></script>
<div id="allSampleContent" class="p-4 w-full">
<script id="code">
function init() {
myDiagram = new go.Diagram('myDiagramDiv', {
'undoManager.isEnabled': true // enable undo & redo
});
// define a simple Node template
myDiagram.nodeTemplate =
new go.Node('Auto')
.add(
// two elements: the Shape will go around the TextBlock
new go.Shape('RoundedRectangle', { strokeWidth: 0, fill: 'white' }) // no border; default fill is white
.bind('fill', 'color'), // Shape.fill is bound to Node.data.color
new go.TextBlock({ margin: 8, font: 'bold 14px sans-serif', stroke: '#333' }) // some room around the text, bold font
.bind('text') // TextBlock.text is bound to Node.data.text
);
// but use the default Link template, by not setting Diagram.linkTemplate
// create the model data that will be represented by Nodes and Links
myDiagram.model = new go.GraphLinksModel(
[
{ key: 1, text: 'Alpha', color: 'lightblue' },
{ key: 2, text: 'Beta', color: 'orange' },
{ key: 3, text: 'Gamma', color: 'lightgreen' },
{ key: 4, text: 'Delta', color: 'pink' }
],
[
{ from: 1, to: 2 },
{ from: 1, to: 3 },
{ from: 2, to: 2 },
{ from: 3, to: 4 },
{ from: 4, to: 1 }
]
);
document.getElementById('blobButton').addEventListener('click', makeBlob);
}
// When the blob is complete, make an anchor tag for it and use the tag to initiate a download
// Works in Chrome, Firefox, Safari, Edge, IE11
function myCallback(blob) {
var url = window.URL.createObjectURL(blob);
var filename = 'myBlobFile.png';
var a = document.createElement('a');
a.style = 'display: none';
a.href = url;
a.download = filename;
// IE 11
if (window.navigator.msSaveBlob !== undefined) {
window.navigator.msSaveBlob(blob, filename);
return;
}
document.body.appendChild(a);
requestAnimationFrame(() => {
a.click();
window.URL.revokeObjectURL(url);
document.body.removeChild(a);
});
}
function makeBlob() {
var blob = myDiagram.makeImageData({ background: 'white', returnType: 'blob', callback: myCallback });
}
window.addEventListener('DOMContentLoaded', init);
</script>
<div id="sample">
<!-- The DIV for the Diagram needs an explicit size or else we won't see anything.
This also adds a border to help see the edges of the viewport. -->
<div id="myDiagramDiv" style="border: solid 1px black; width: 400px; height: 400px"></div>
<button id="blobButton">Make Blob and Download</button>
<p>
This sample shows how to use <a>Diagram.makeImageData</a> with the <code>returnType: "blob"</code> option and the necessary <code>callback</code> option. It
also shows how to download a file that the page has generated.
</p>
</div>
</div>
<!-- * * * * * * * * * * * * * -->
<!-- End of GoJS sample code -->
</div>
<div id="allTagDescriptions" class="p-4 w-full max-w-screen-xl mx-auto">
<hr/>
<h3 class="text-xl">GoJS Features in this sample</h3>
<!-- blacklist tags that do not correspond to a specific GoJS feature -->
<h4>Exporting Raster Images</h4>
<p>
<b>GoJS</b> has two functions for creating raster images: <a href="../api/symbols/Diagram.html#makeImageData" target="api">Diagram.makeImageData</a>, which outputs a Base64 image data string, and <a href="../api/symbols/Diagram.html#makeImage" target="api">Diagram.makeImage</a>, which is a convenience function that calls <a href="../api/symbols/Diagram.html#makeImageData" target="api">Diagram.makeImageData</a> and returns a new HTMLImageElement with the image data as its source. Both functions have the same single argument, a JavaScript Object that contains several definable properties, enumerated in the documentation.
More information can be found in the <a href="../intro/makingImages.html">GoJS Intro</a>.
</p>
<p>
<a href="../samples/index.html#export">Related samples</a>
</p>
<hr>
</div>
</div>
</body>
<!-- This script is part of the gojs.net website, and is not needed to run the sample -->
<script src="../assets/js/goSamples.js"></script>
</html>