<!--
Copyright (c) 2006-2013, JGraph Ltd
Overlays example for mxGraph. This example demonstrates cell
highlighting, overlays and handling click and double click
events. See also: events.html for more event handling.
-->
<html>
<head>
<title>Overlays 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).
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
{
// Creates the graph inside the given container
var graph = new mxGraph(container);
// Disables basic selection and cell handling
graph.setEnabled(false);
// Highlights the vertices when the mouse enters
var highlight = new mxCellTracker(graph, '#00FF00');
// Enables tooltips for the overlays
graph.setTooltips(true);
// Installs a handler for click events in the graph
// that toggles the overlay for the respective cell
graph.addListener(mxEvent.CLICK, function(sender, evt)
{
var cell = evt.getProperty('cell');
if (cell != null)
{
var overlays = graph.getCellOverlays(cell);
if (overlays == null)
{
// Creates a new overlay with an image and a tooltip
var overlay = new mxCellOverlay(
new mxImage('editors/images/overlays/check.png', 16, 16),
'Overlay tooltip');
// Installs a handler for clicks on the overlay
overlay.addListener(mxEvent.CLICK, function(sender, evt2)
{
mxUtils.alert('Overlay clicked');
});
// Sets the overlay for the cell in the graph
graph.addCellOverlay(cell, overlay);
}
else
{
graph.removeCellOverlays(cell);
}
}
});
// Installs a handler for double click events in the graph
// that shows an alert box
graph.addListener(mxEvent.DOUBLE_CLICK, function(sender, evt)
{
var cell = evt.getProperty('cell');
mxUtils.alert('Doubleclick: '+((cell != null) ? 'Cell' : 'Graph'));
evt.consume();
});
// 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 v1 = graph.insertVertex(parent, null, 'Click,', 20, 20, 60, 40);
var v2 = graph.insertVertex(parent, null, 'Doubleclick', 200, 150, 100, 40);
var e1 = graph.insertEdge(parent, null, '', v1, v2);
}
finally
{
// Updates the display
graph.getModel().endUpdate();
}
}
};
</script>
</head>
<!-- Page passes the container for the graph to the program -->
<body onload="main(document.getElementById('graphContainer'))">
<!-- Creates a container for the graph with a grid wallpaper -->
<div id="graphContainer"
style="overflow:hidden;position:relative;width:321px;height:241px;background:url('editors/images/grid.gif')">
</div>
</body>
</html>