gojs
Version:
Interactive diagrams, charts, and graphs, such as trees, flowcharts, orgcharts, UML, BPMN, or business diagrams
106 lines (93 loc) • 3.85 kB
HTML
<html>
<head>
<meta charset="UTF-8">
<title>Minimal Image Blob and Download</title>
<meta name="description" content="Minimal, showing image Blob creation and download with Diagram.makeImageData." />
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Copyright 1998-2020 by Northwoods Software Corporation. -->
<script src="../release/go.js"></script>
<script src="../assets/js/goSamples.js"></script> <!-- this is only for the GoJS Samples framework -->
<script id="code">
function init() {
if (window.goSamples) goSamples(); // init for these samples -- you don't need to call this
var $ = go.GraphObject.make; // for conciseness in defining templates
myDiagram = $(go.Diagram, "myDiagramDiv", // create a Diagram for the DIV HTML element
{
"undoManager.isEnabled": true // enable undo & redo
});
// define a simple Node template
myDiagram.nodeTemplate =
$(go.Node, "Auto", // the Shape will go around the TextBlock
$(go.Shape, "RoundedRectangle", { strokeWidth: 0 },
// Shape.fill is bound to Node.data.color
new go.Binding("fill", "color")),
$(go.TextBlock,
{ margin: 8 }, // some room around the text
// TextBlock.text is bound to Node.data.key
new go.Binding("text", "key"))
);
// 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: "Alpha", color: "lightblue" },
{ key: "Beta", color: "orange" },
{ key: "Gamma", color: "lightgreen" },
{ key: "Delta", color: "pink" }
],
[
{ from: "Alpha", to: "Beta" },
{ from: "Alpha", to: "Gamma" },
{ from: "Beta", to: "Beta" },
{ from: "Gamma", to: "Delta" },
{ from: "Delta", to: "Alpha" }
]);
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
// * IE11, Edge
// * Firefox
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(function() {
a.click();
window.URL.revokeObjectURL(url);
document.body.removeChild(a);
});
}
function makeBlob() {
var blob = myDiagram.makeImageData({ background: "white", returnType: "blob", callback: myCallback });
}
</script>
</head>
<body onload="init()">
<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.
</p>
<p>
Blobs may not be supported or work consistently on all browsers.
This code was tested with Chrome, Firefox, IE11 and Edge.
</p>
</div>
</body>
</html>