maxGraph/javascript/examples/dynamicloading.html

248 lines
7.2 KiB
HTML

<!--
Copyright (c) 2006-2013, JGraph Ltd
Dynamic loading example for mxGraph. This example demonstrates loading
graph model data dynamically to limit the number of cells in the model.
-->
<html>
<head>
<title>Dynamic loading example for mxGraph</title>
<!-- Sets the basepath for the library if not in same directory -->
<script type="text/javascript">
mxBasePath = '../src';
</script>
<!-- Loads and initializes the library -->
<script type="text/javascript" src="../src/js/mxClient.js"></script>
<!-- Example code -->
<script type="text/javascript">
// Program starts here. Creates a sample graph in the
// DOM node with the specified ID. This function is invoked
// from the onLoad event handler of the document (see below).
// Global variable to make sure each cell in a response has
// a unique ID throughout the complete life of the program,
// in a real-life setup each cell should have an external
// ID on the business object or else the cell ID should be
// globally unique for the lifetime of the graph model.
var requestId = 0;
function main(container)
{
// Checks if browser is supported
if (!mxClient.isBrowserSupported())
{
// Displays an error message if the browser is
// not supported.
mxUtils.error('Browser is not supported!', 200, false);
}
else
{
// Speedup the animation
mxText.prototype.enableBoundingBox = false;
// Creates the graph inside the given container
var graph = new mxGraph(container);
// Disables all built-in interactions
graph.setEnabled(false);
// Handles clicks on cells
graph.addListener(mxEvent.CLICK, function(sender, evt)
{
var cell = evt.getProperty('cell');
if (cell != null)
{
load(graph, cell);
}
});
// Changes the default vertex style in-place
var style = graph.getStylesheet().getDefaultVertexStyle();
style[mxConstants.STYLE_SHAPE] = mxConstants.SHAPE_ELLIPSE;
style[mxConstants.STYLE_PERIMETER] = mxPerimeter.EllipsePerimeter;
style[mxConstants.STYLE_GRADIENTCOLOR] = 'white';
// Gets the default parent for inserting new cells. This
// is normally the first child of the root (ie. layer 0).
var parent = graph.getDefaultParent();
var cx = graph.container.clientWidth / 2;
var cy = graph.container.clientHeight / 2;
var cell = graph.insertVertex(parent, '0-0', '0-0', cx - 20, cy - 15, 60, 40);
// Animates the changes in the graph model
graph.getModel().addListener(mxEvent.CHANGE, function(sender, evt)
{
var changes = evt.getProperty('edit').changes;
mxEffects.animateChanges(graph, changes);
});
load(graph, cell);
}
};
// Loads the links for the given cell into the given graph
// by requesting the respective data in the server-side
// (implemented for this demo using the server-function)
function load(graph, cell)
{
if (graph.getModel().isVertex(cell))
{
var cx = graph.container.clientWidth / 2;
var cy = graph.container.clientHeight / 2;
// Gets the default parent for inserting new cells. This
// is normally the first child of the root (ie. layer 0).
var parent = graph.getDefaultParent();
// Adds cells to the model in a single step
graph.getModel().beginUpdate();
try
{
var xml = server(cell.id);
var doc = mxUtils.parseXml(xml);
var dec = new mxCodec(doc);
var model = dec.decode(doc.documentElement);
// Removes all cells which are not in the response
for (var key in graph.getModel().cells)
{
var tmp = graph.getModel().getCell(key);
if (tmp != cell &&
graph.getModel().isVertex(tmp))
{
graph.removeCells([tmp]);
}
}
// Merges the response model with the client model
graph.getModel().mergeChildren(model.getRoot().getChildAt(0), parent);
// Moves the given cell to the center
var geo = graph.getModel().getGeometry(cell);
if (geo != null)
{
geo = geo.clone();
geo.x = cx - geo.width / 2;
geo.y = cy - geo.height / 2;
graph.getModel().setGeometry(cell, geo);
}
// Creates a list of the new vertices, if there is more
// than the center vertex which might have existed
// previously, then this needs to be changed to analyze
// the target model before calling mergeChildren above
var vertices = [];
for (var key in graph.getModel().cells)
{
var tmp = graph.getModel().getCell(key);
if (tmp != cell && model.isVertex(tmp))
{
vertices.push(tmp);
// Changes the initial location "in-place"
// to get a nice animation effect from the
// center to the radius of the circle
var geo = model.getGeometry(tmp);
if (geo != null)
{
geo.x = cx - geo.width / 2;
geo.y = cy - geo.height / 2;
}
}
}
// Arranges the response in a circle
var cellCount = vertices.length;
var phi = 2 * Math.PI / cellCount;
var r = Math.min(graph.container.clientWidth / 4,
graph.container.clientHeight / 4);
for (var i = 0; i < cellCount; i++)
{
var geo = graph.getModel().getGeometry(vertices[i]);
if (geo != null)
{
geo = geo.clone();
geo.x += r * Math.sin(i * phi);
geo.y += r * Math.cos(i * phi);
graph.getModel().setGeometry(vertices[i], geo);
}
}
}
finally
{
// Updates the display
graph.getModel().endUpdate();
}
}
};
// Simulates the existence of a server that can crawl the
// big graph with a certain depth and create a graph model
// for the traversed cells, which is then sent to the client
function server(cellId)
{
// Increments the request ID as a prefix for the cell IDs
requestId++;
// Creates a local graph with no display
var graph = new mxGraph();
// Gets the default parent for inserting new cells. This
// is normally the first child of the root (ie. layer 0).
var parent = graph.getDefaultParent();
// Adds cells to the model in a single step
graph.getModel().beginUpdate();
try
{
var v0 = graph.insertVertex(parent, cellId, 'Dummy', 0, 0, 60, 40);
var cellCount = parseInt(Math.random() * 16) + 4;
// Creates the random links and cells for the response
for (var i = 0; i < cellCount; i++)
{
var id = requestId + '-' + i;
var v = graph.insertVertex(parent, id, id, 0, 0, 60, 40);
var e = graph.insertEdge(parent, null, 'Link ' + i, v0, v);
}
}
finally
{
// Updates the display
graph.getModel().endUpdate();
}
var enc = new mxCodec();
var node = enc.encode(graph.getModel());
return mxUtils.getXml(node);
};
</script>
</head>
<!-- Page passes the container for the graph to the program -->
<body onload="main(document.getElementById('graphContainer'))" style="overflow:hidden;">
<!-- Creates a container for the graph with a grid wallpaper. Make sure to define the position
and overflow attributes! See comments on the adding of the size-listener on line 54 ff! -->
<div id="graphContainer"
style="overflow:visible;position:absolute;width:100%;height:100%;background:url('editors/images/grid.gif');cursor:default;">
</div>
</body>
</html>