<!--
Copyright (c) 2006-2013, JGraph Ltd
Server-View example for mxGraph. This example demonstrates using
a server-side image of the graph as the diagram in the client. This
may be used to improve drawing-speed in older browser and on devices
with slower processors.
-->
<html>
<head>
<title>mxGraph using Server-side Image</title>
<!-- Sets the basepath for the library if not in same directory -->
<script type="text/javascript">
mxBasePath = '/mxgraph/javascript/src';
</script>
<!-- Loads and initializes the library -->
<script type="text/javascript" src="/mxgraph/javascript/src/js/mxClient.js"></script>
<!-- Overrides certain methods required for the server-side-image to be used. -->
<script type="text/javascript">
// Makes the background of the in-place editor non-transparent
var previousStartEditing = mxCellEditor.prototype.startEditing;
mxCellEditor.prototype.startEditing = function (cell, trigger)
{
previousStartEditing.apply(this, arguments);
var state = this.graph.getView().getState(cell);
if (state != null)
{
var color = mxUtils.getValue(state.style, mxConstants.STYLE_FILLCOLOR, 'white');
this.textarea.style.background = color;
}
};
// Replaces the event firing mechanism in the graph view since there are
// no longer any DOM elements that fire events for the actual states we
// have to find the state under the mouse using graph.getCellAt and then
// fire the event for the state from here instead.
// FIXME: Since we do not render the label we don't have the label bounds
// here which means hit detection will only work for the vertex bounds,
// the edge but not for overlapping labels or most part of the edge labels.
mxGraphView.prototype.installListeners = function()
{
var graph = this.graph;
var container = graph.container;
if (container != null)
{
mxEvent.addGestureListeners(container,
mxUtils.bind(this, function(evt)
{
var pt = mxUtils.convertPoint(graph.container,
mxEvent.getClientX(evt), mxEvent.getClientY(evt));
var cell = graph.getCellAt(pt.x, pt.y);
var state = this.getState(cell);
if (state != null)
{
graph.fireMouseEvent(mxEvent.MOUSE_DOWN,
new mxMouseEvent(evt, state));
}
// Condition to avoid scrollbar events starting a rubberband
// selection
else if (this.isContainerEvent(evt) &&
((!mxClient.IS_IE &&
!mxClient.IS_GC && !mxClient.IS_OP && !mxClient.IS_SF) ||
!this.isScrollEvent(evt)))
{
graph.fireMouseEvent(mxEvent.MOUSE_DOWN,
new mxMouseEvent(evt));
}
}),
mxUtils.bind(this, function(evt)
{
var pt = mxUtils.convertPoint(graph.container,
mxEvent.getClientX(evt), mxEvent.getClientY(evt));
var cell = graph.getCellAt(pt.x, pt.y);
var state = this.getState(cell);
if (state != null)
{
graph.fireMouseEvent(mxEvent.MOUSE_MOVE,
new mxMouseEvent(evt, state));
}
else if (this.isContainerEvent(evt))
{
graph.fireMouseEvent(mxEvent.MOUSE_MOVE,
new mxMouseEvent(evt));
}
}),
mxUtils.bind(this, function(evt)
{
var pt = mxUtils.convertPoint(graph.container,
mxEvent.getClientX(evt), mxEvent.getClientY(evt));
var cell = graph.getCellAt(pt.x, pt.y);
var state = this.getState(cell);
if (state != null)
{
graph.fireMouseEvent(mxEvent.MOUSE_UP,
new mxMouseEvent(evt, state));
}
else if (this.isContainerEvent(evt))
{
graph.fireMouseEvent(mxEvent.MOUSE_UP,
new mxMouseEvent(evt));
}
}));
// Adds listener for double click handling on background
mxEvent.addListener(container, 'dblclick',
mxUtils.bind(this, function(evt)
{
var pt = mxUtils.convertPoint(graph.container,
mxEvent.getClientX(evt), mxEvent.getClientY(evt));
var cell = graph.getCellAt(pt.x, pt.y);
graph.dblClick(evt, cell);
})
);
// Adds basic listeners for graph event dispatching outside of the
// container and finishing the handling of a single gesture
mxEvent.addGestureListeners(document,
mxUtils.bind(this, function(evt)
{
if (this.isContainerEvent(evt))
{
graph.popupMenuHandler.hideMenu();
}
}),
mxUtils.bind(this, function(evt)
{
// Hides the tooltip if mouse is outside container
if (graph.tooltipHandler != null &&
graph.tooltipHandler.isHideOnHover())
{
graph.tooltipHandler.hide();
}
if (this.captureDocumentGesture &&
graph.isMouseDown &&
!mxEvent.isConsumed(evt))
{
graph.fireMouseEvent(mxEvent.MOUSE_MOVE,
new mxMouseEvent(evt));
}
}),
mxUtils.bind(this, function(evt)
{
if (this.captureDocumentGesture)
{
graph.fireMouseEvent(mxEvent.MOUSE_UP,
new mxMouseEvent(evt));
}
})
);
}
};
</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 the 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);
// Holds the current image
var img = null;
var loader = new Image();
loader.src = 'images/loading.gif';
loader.style.zIndex = 1;
loader.style.visibility = 'hidden';
loader.style.position = 'absolute';
graph.container.insertBefore(loader, graph.container.firstChild);
// Disables the DOM-based rendering in the graph and updates the
// display image on each validation step using the Export servlet
// on the graph
graph.view.rendering = false;
// Installs a post-validation repaint of the complete graph
graph.view.validate = function()
{
loader.style.left = graph.container.scrollLeft + graph.container.clientWidth / 2 - 32;
loader.style.top = graph.container.scrollTop + graph.container.clientHeight / 2 - 32;
loader.style.visibility = 'visible';
mxGraphView.prototype.validate.apply(this, arguments);
var t0 = new Date().getTime();
var bounds = graph.getGraphBounds();
// Note that we send out an XML version of the view which
// allows us to keep most customizations on the client-side.
// No deltas are used here, the complete view is sent to the
// server on each update.
var node = mxUtils.getViewXml(graph, 1);
var xml = encodeURIComponent(mxUtils.getXml(node));
var onload = function(req)
{
var dt = (new Date().getTime() - t0) / 1000;
//mxLog.debug('post returned after '+dt+' secs');
if (req.getStatus() == 200)
{
var image =new Image();
// Disable DnD events on images in IE. FIXME: Rubberband
// events are ignored in IE when starting on the image.
if (mxClient.IS_IE)
{
graph.view.isContainerEvent = function(evt)
{
var source = mxEvent.getSource(evt);
return (source == image ||
source == this.graph.container ||
source.parentNode == this.backgroundPane ||
(source.parentNode != null &&
source.parentNode.parentNode == this.backgroundPane) ||
source == this.canvas.parentNode ||
source == this.canvas ||
source == this.backgroundPane ||
source == this.drawPane ||
source == this.overlayPane);
};
}
// Less flickering if the old image is removed after
// the new image was received from the server
image.onload = function()
{
if (img != null)
{
img.parentNode.removeChild(img);
}
img = image;
graph.container.insertBefore(img, graph.container.firstChild);
loader.style.visibility = 'hidden';
var dt = (new Date().getTime() - t0) / 1000;
//mxLog.debug('received '+img.clientWidth+'x'+img.clientHeight+' pixels in '+dt+' secs');
graph.setEnabled(true);
};
// URL contains timestamp to avoid caching in the browser
image.src = '/ServerView?'+new Date().getTime();
image.style.position = 'absolute';
image.style.left = bounds.x - 4;
image.style.top = bounds.y - 4;
image.style.zIndex = -1;
}
};
var onerror = function(req)
{
//mxLog.debug('error: '+req.getStatus());
}
//mxLog.debug('sent '+(xml.length/1024)+' KB');
graph.setEnabled(false);
new mxXmlRequest('/ServerView', 'xml='+xml).send(onload, onerror);
};
// Uncomment the following if you want the container
// to fit the size of the graph
//graph.setResizeContainer(true);
// Enables rubberband selection
new mxRubberband(graph);
graph.setConnectable(true);
graph.setPanning(true);
graph.setTooltips(true);
// Gets the default parent for inserting new cells. This
// is normally the first child of the root (ie. layer 0).
var parent = graph.getDefaultParent();
//mxLog.show();
// Adds cells to the model in a single step
graph.getModel().beginUpdate();
try
{
var v1 = graph.insertVertex(parent, null, 'Hello,', 20, 20, 80, 30);
var v2 = graph.insertVertex(parent, null, 'World!', 200, 150, 80, 30);
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:auto;width:500px;height:500px;border: black solid 1px;cursor:default;">
</div>
<br>
<strong>Important:</strong>
<p>
To use this example, start com.mxgraph.examples.web.Main in Java
and point your<br>browser to:
<a href="http://localhost:8080/mxgraph/javascript/examples/serverview.html">http://localhost:8080/mxgraph/javascript/examples/serverview.html</a>
</p>
</body>
</html>