maxGraph/javascript/examples/grapheditor/www/js/Editor.js

/**
 * $Id: Editor.js,v 1.43 2012-06-06 11:37:57 gaudenz Exp $
 * Copyright (c) 2006-2012, JGraph Ltd
 */
// Specifies if local storage should be used (eg. on the iPad which has no filesystem)
var useLocalStorage = (mxClient.IS_TOUCH || urlParams['storage'] == 'local') && typeof(localStorage) != 'undefined';
var fileSupport = window.File != null && window.FileReader != null && window.FileList != null;

// Specifies if connector should be shown on selected cells
var touchStyle = mxClient.IS_TOUCH || urlParams['touch'] == '1';

// Counts open editor tabs (must be global for cross-window access)
var counter = 0;

// Cross-domain window access is not allowed in FF, so if we
// were opened from another domain then this will fail. 
try
{
	var op = window;
	
	while (op.opener != null && !isNaN(op.opener.counter))
	{
		op = op.opener;
	}
	
	// Increments the counter in the first opener in the chain
	if (op != null)
	{
		op.counter++;
		counter = op.counter;
	}
}
catch (e)
{
	// ignore
}

/**
 * Editor constructor executed on page load.
 */
Editor = function()
{
	mxEventSource.call(this);
	this.init();
	this.initStencilRegistry();
	this.graph = new Graph();
	this.outline = new mxOutline(this.graph);
	this.outline.updateOnPan = true;
	this.undoManager = this.createUndoManager();
	this.status = '';
	
	// Contains the name which was used for the last save. Default value is null.
	this.filename = null;

	this.getOrCreateFilename = function()
	{
		return this.filename || mxResources.get('drawing', [counter]) + '.xml';
	};
	
	this.getFilename = function()
	{
		return this.filename;
	};
	
	// Sets the status and fires a statusChanged event
	this.setStatus = function(value)
	{
		this.status = value;
		this.fireEvent(new mxEventObject('statusChanged'));
	};
	
	// Returns the current status
	this.getStatus = function()
	{
		return this.status;
	};

	// Contains the current modified state of the diagram. This is false for
	// new diagrams and after the diagram was saved.
	this.modified = false;

	// Updates modified state if graph changes
	this.graph.getModel().addListener(mxEvent.CHANGE, mxUtils.bind(this, function()
	{
		this.modified = true;
	}));
	
	// Installs dialog if browser window is closed without saving
	// This must be disabled during save and image export
	window.onbeforeunload = function()
	{
		if (modified)
		{
			return mxResources.get('allChangesLost');
		}
	};
	
	// Sets persistent graph state defaults
	this.graph.resetViewOnRootChange = false;
	this.graph.scrollbars = true;
	this.graph.background = null;
};

// Editor inherits from mxEventSource
mxUtils.extend(Editor, mxEventSource);

/**
 * Sets the XML node for the current diagram.
 */
Editor.prototype.setGraphXml = function(node)
{
	var dec = new mxCodec(node.ownerDocument);
	
	if (node.nodeName == 'mxGraphModel')
	{
		this.graph.view.scale = Number(node.getAttribute('scale') || 1);
		this.graph.gridEnabled = node.getAttribute('grid') != '0';
		this.graph.graphHandler.guidesEnabled = node.getAttribute('guides') != '0';
		this.graph.setTooltips(node.getAttribute('tooltips') != '0');
		this.graph.setConnectable(node.getAttribute('connect') != '0');
		this.graph.foldingEnabled = node.getAttribute('fold') != '0';
		this.graph.scrollbars = node.getAttribute('scrollbars') != '0';
		
		if (!this.graph.scrollbars)
		{
			this.graph.container.scrollLeft = 0;
			this.graph.container.scrollTop = 0;
			this.graph.view.translate.x = Number(node.getAttribute('dx') || 0);
			this.graph.view.translate.y = Number(node.getAttribute('dy') || 0);
		}

		this.graph.pageVisible = node.getAttribute('page') == '1';
		this.graph.pageBreaksVisible = this.graph.pageVisible; 
		this.graph.preferPageSize = this.graph.pageBreaksVisible;
		
		// Loads the persistent state settings
		var ps = node.getAttribute('pageScale');
		
		if (ps != null)
		{
			this.graph.pageScale = ps;
		}
		else
		{
			this.graph.pageScale = 1.5;
		}
		
		var pw = node.getAttribute('pageWidth');
		var ph = node.getAttribute('pageHeight');
		
		if (pw != null && ph != null)
		{
			this.graph.pageFormat = new mxRectangle(0, 0, parseFloat(pw), parseFloat(ph));
		}

		// Loads the persistent state settings
		var bg = node.getAttribute('background');
		
		if (bg != null && bg.length > 0)
		{
			this.graph.background = bg;
		}
		
		dec.decode(node, this.graph.getModel());
		this.updateGraphComponents();
	}
};

/**
 * Returns the XML node that represents the current diagram.
 */
Editor.prototype.getGraphXml = function()
{
	var enc = new mxCodec(mxUtils.createXmlDocument());
	var node = enc.encode(this.graph.getModel());

	if (this.graph.view.translate.x != 0 || this.graph.view.translate.y != 0)
	{
		node.setAttribute('dx', Math.round(this.graph.view.translate.x * 100) / 100);
		node.setAttribute('dy', Math.round(this.graph.view.translate.y * 100) / 100);
	}
	
	if (this.graph.view.scale != 1)
	{
		node.setAttribute('scale', Math.round(this.graph.view.scale * 1000) / 1000);
	}
	
	node.setAttribute('grid', (this.graph.isGridEnabled()) ? '1' : '0');
	node.setAttribute('guides', (this.graph.graphHandler.guidesEnabled) ? '1' : '0');
	node.setAttribute('guides', (this.graph.graphHandler.guidesEnabled) ? '1' : '0');
	node.setAttribute('tooltips', (this.graph.tooltipHandler.isEnabled()) ? '1' : '0');
	node.setAttribute('connect', (this.graph.connectionHandler.isEnabled()) ? '1' : '0');	
	node.setAttribute('fold', (this.graph.foldingEnabled) ? '1' : '0');
	node.setAttribute('page', (this.graph.pageVisible) ? '1' : '0');
	node.setAttribute('pageScale', this.graph.pageScale);
	node.setAttribute('pageWidth', this.graph.pageFormat.width);
	node.setAttribute('pageHeight', this.graph.pageFormat.height);
	
	if (!this.graph.scrollbars)
	{
		node.setAttribute('scrollbars', '0');
	}

	if (this.graph.background != null)
	{
		node.setAttribute('background', this.graph.background);
	}
	
	return node;
};

/**
 * Keeps the graph container in sync with the persistent graph state
 */
Editor.prototype.updateGraphComponents = function()
{
	var graph = this.graph;
	var outline = this.outline;
	
	if (graph.container != null && outline.outline.container != null)
	{
		if (graph.background != null)
		{
			if (graph.background == 'none')
			{
				graph.container.style.backgroundColor = 'transparent';
			}
			else
			{
				if (graph.view.backgroundPageShape != null)
				{
					graph.view.backgroundPageShape.fill = graph.background;
					graph.view.backgroundPageShape.reconfigure();
				}
				
				graph.container.style.backgroundColor = graph.background;
			}
		}
		else
		{
			graph.container.style.backgroundColor = '';
		}

		if (graph.pageVisible)
		{
			graph.container.style.backgroundColor = '#ebebeb';
			graph.container.style.borderStyle = 'solid';
			graph.container.style.borderColor = '#e5e5e5';
			graph.container.style.borderTopWidth = '1px';
			graph.container.style.borderLeftWidth = '1px';
			graph.container.style.borderRightWidth = '0px';
			graph.container.style.borderBottomWidth = '0px';
		}
		else
		{
			graph.container.style.border = '';
		}
		
		outline.outline.container.style.backgroundColor = graph.container.style.backgroundColor;

		if (outline.outline.pageVisible != graph.pageVisible ||
			outline.outline.pageScale != graph.pageScale)
		{
			outline.outline.pageScale = graph.pageScale;
			outline.outline.pageVisible = graph.pageVisible;
			outline.outline.view.validate();
		}
		
		if (graph.scrollbars && graph.container.style.overflow == 'hidden' && !touchStyle)
		{
			graph.container.style.overflow = 'auto';
		}
		else if (!graph.scrollbars || touchStyle)
		{
			graph.container.style.overflow = 'hidden';
		}
		
		// Transparent.gif is a workaround for focus repaint problems in IE
		var noBackground = (mxClient.IS_IE && document.documentMode >= 9) ? 'url(images/transparent.gif)' : 'none';
		graph.container.style.backgroundImage = (!graph.pageVisible && graph.isGridEnabled()) ? 'url(images/grid.gif)' : noBackground;

		if (graph.view.backgroundPageShape != null)
		{
			graph.view.backgroundPageShape.node.style.backgroundImage = (this.graph.isGridEnabled()) ? 'url(images/grid.gif)' : 'none';
		}
	}
};

/**
 * Initializes the environment.
 */
Editor.prototype.init = function()
{
	// Adds stylesheet for IE6
	if (mxClient.IS_IE6)
	{
		mxClient.link('stylesheet', CSS_PATH + '/grapheditor-ie6.css');
	}

	// Adds stylesheet for touch devices
	if (touchStyle)
	{
		mxClient.link('stylesheet', CSS_PATH + '/grapheditor-touch.css');
	}

	// Adds required resources (disables loading of fallback properties, this can only
	// be used if we know that all keys are defined in the language specific file)
	mxResources.loadDefaultBundle = false;
	mxResources.add(RESOURCE_BASE);

	// Makes the connection hotspot smaller
	mxConstants.DEFAULT_HOTSPOT = 0.3;

	var mxConnectionHandlerCreateMarker = mxConnectionHandler.prototype.createMarker;
	mxConnectionHandler.prototype.createMarker = function()
	{
		var marker = mxConnectionHandlerCreateMarker.apply(this, arguments);
		
		// Overrides to ignore hotspot only for target terminal
		marker.intersects = mxUtils.bind(this, function(state, evt)
		{
			if (this.isConnecting())
			{
				return true;
			}
			
			return mxCellMarker.prototype.intersects.apply(marker, arguments);
		});
		
		return marker;
	};

	// Makes the shadow brighter
	mxConstants.SHADOWCOLOR = '#d0d0d0';
	
	// Changes some default colors
	mxConstants.HANDLE_FILLCOLOR = '#99ccff';
	mxConstants.HANDLE_STROKECOLOR = '#0088cf';
	mxConstants.VERTEX_SELECTION_COLOR = '#00a8ff';
	mxConstants.OUTLINE_COLOR = '#00a8ff';
	mxConstants.OUTLINE_HANDLE_FILLCOLOR = '#99ccff';
	mxConstants.OUTLINE_HANDLE_STROKECOLOR = '#00a8ff';
	mxConstants.CONNECT_HANDLE_FILLCOLOR = '#cee7ff';
	mxConstants.EDGE_SELECTION_COLOR = '#00a8ff';
	mxConstants.DEFAULT_VALID_COLOR = '#00a8ff';
	mxConstants.LABEL_HANDLE_FILLCOLOR = '#cee7ff';
	mxConstants.GUIDE_COLOR = '#0088cf';

	// TODO: Add option for setting pageScale
	mxGraph.prototype.pageBreakColor = '#c0c0c0';
	mxGraph.prototype.pageScale = 1;
	
	// Increases default rubberband opacity (default is 20)
	mxRubberband.prototype.defaultOpacity = 30;
	
	// Changes border color of background page shape
	mxGraphView.prototype.createBackgroundPageShape = function(bounds)
	{
		return new mxRectangleShape(bounds, this.graph.background || 'white', '#cacaca');
	};

	// Fits the number of background pages to the graph
	mxGraphView.prototype.getBackgroundPageBounds = function()
	{
		var gb = this.getGraphBounds();
		
		// Computes unscaled, untranslated graph bounds
		var x = (gb.width > 0) ? gb.x / this.scale - this.translate.x : 0;
		var y = (gb.height > 0) ? gb.y / this.scale - this.translate.y : 0;
		var w = gb.width / this.scale;
		var h = gb.height / this.scale;
		
		var fmt = this.graph.pageFormat;
		var ps = this.graph.pageScale;

		var pw = fmt.width * ps;
		var ph = fmt.height * ps;

		var x0 = Math.floor(Math.min(0, x) / pw);
		var y0 = Math.floor(Math.min(0, y) / ph);
		var xe = Math.ceil(Math.max(1, x + w) / pw);
		var ye = Math.ceil(Math.max(1, y + h) / ph);
		
		var rows = xe - x0;
		var cols = ye - y0;

		var bounds = new mxRectangle(this.scale * (this.translate.x + x0 * pw), this.scale *
				(this.translate.y + y0 * ph), this.scale * rows * pw, this.scale * cols * ph);
		
		return bounds;
	};
	
	// Add panning for background page in VML
	var graphPanGraph = mxGraph.prototype.panGraph;
	mxGraph.prototype.panGraph = function(dx, dy)
	{
		graphPanGraph.apply(this, arguments);
		
		if ((this.dialect != mxConstants.DIALECT_SVG && this.view.backgroundPageShape != null) &&
			(!this.useScrollbarsForPanning || !mxUtils.hasScrollbars(this.container)))
		{
			this.view.backgroundPageShape.node.style.marginLeft = dx + 'px';
			this.view.backgroundPageShape.node.style.marginTop = dy + 'px';
		}
	};
	
	// Uses HTML for background pages (to support grid background image)
	mxGraphView.prototype.validateBackground = function()
	{
		var bg = this.graph.getBackgroundImage();
		
		if (bg != null)
		{
			if (this.backgroundImage == null || this.backgroundImage.image != bg.src)
			{
				if (this.backgroundImage != null)
				{
					this.backgroundImage.destroy();
				}
				
				var bounds = new mxRectangle(0, 0, 1, 1);
				
				this.backgroundImage = new mxImageShape(bounds, bg.src);
				this.backgroundImage.dialect = this.graph.dialect;
				this.backgroundImage.init(this.backgroundPane);
				this.backgroundImage.redraw();
			}
			
			this.redrawBackgroundImage(this.backgroundImage, bg);
		}
		else if (this.backgroundImage != null)
		{
			this.backgroundImage.destroy();
			this.backgroundImage = null;
		}
		
		if (this.graph.pageVisible)
		{
			var bounds = this.getBackgroundPageBounds();
			
			if (this.backgroundPageShape == null)
			{
				this.backgroundPageShape = this.createBackgroundPageShape(bounds);
				this.backgroundPageShape.scale = 1;
				this.backgroundPageShape.isShadow = true;
				this.backgroundPageShape.dialect = mxConstants.DIALECT_STRICTHTML;
				this.backgroundPageShape.init(this.graph.container);
				// Required for the browser to render the background page in correct order
				this.graph.container.firstChild.style.position = 'absolute';
				this.graph.container.insertBefore(this.backgroundPageShape.node, this.graph.container.firstChild);
				this.backgroundPageShape.redraw();
				
				this.backgroundPageShape.node.className = 'backgroundPage';
				
				// Adds listener for double click handling on background
				mxEvent.addListener(this.backgroundPageShape.node, 'dblclick',
					mxUtils.bind(this, function(evt)
					{
						this.graph.dblClick(evt);
					})
				);
				
				var md = (mxClient.IS_TOUCH) ? 'touchstart' : 'mousedown';
				var mm = (mxClient.IS_TOUCH) ? 'touchmove' : 'mousemove';
				var mu = (mxClient.IS_TOUCH) ? 'touchend' : 'mouseup';

				// Adds basic listeners for graph event dispatching outside of the
				// container and finishing the handling of a single gesture
				mxEvent.addListener(this.backgroundPageShape.node, md,
					mxUtils.bind(this, function(evt)
					{
						this.graph.fireMouseEvent(mxEvent.MOUSE_DOWN, new mxMouseEvent(evt));
					})
				);
				mxEvent.addListener(this.backgroundPageShape.node, mm,
					mxUtils.bind(this, function(evt)
					{
						// Hides the tooltip if mouse is outside container
						if (this.graph.tooltipHandler != null &&
								this.graph.tooltipHandler.isHideOnHover())
						{
							this.graph.tooltipHandler.hide();
						}
						
						if (this.graph.isMouseDown &&
							!mxEvent.isConsumed(evt))
						{
							this.graph.fireMouseEvent(mxEvent.MOUSE_MOVE,
								new mxMouseEvent(evt));
						}
					})
				);
				mxEvent.addListener(this.backgroundPageShape.node, mu,
					mxUtils.bind(this, function(evt)
					{
						this.graph.fireMouseEvent(mxEvent.MOUSE_UP,
								new mxMouseEvent(evt));
					})
				);
			}
			else
			{
				this.backgroundPageShape.scale = 1;
				this.backgroundPageShape.bounds = bounds;
				this.backgroundPageShape.redraw();
			}
		}
		else if (this.backgroundPageShape != null)
		{
			this.backgroundPageShape.destroy();
			this.backgroundPageShape = null;
		}
	};
	
	// Draws page breaks only within the page
	mxGraph.prototype.updatePageBreaks = function(visible, width, height)
	{
		var scale = this.view.scale;
		var tr = this.view.translate;
		var fmt = this.pageFormat;
		var ps = scale * this.pageScale;

		var bounds2 = this.view.getBackgroundPageBounds();

		width = bounds2.width;
		height = bounds2.height;
		var bounds = new mxRectangle(scale * tr.x, scale * tr.y,
				fmt.width * ps, fmt.height * ps);

		// Does not show page breaks if the scale is too small
		visible = visible && Math.min(bounds.width, bounds.height) > this.minPageBreakDist;

		var horizontalCount = (visible) ? Math.ceil(width / bounds.width) - 1 : 0;
		var verticalCount = (visible) ? Math.ceil(height / bounds.height) - 1 : 0;
		var right = bounds2.x + width;
		var bottom = bounds2.y + height;

		if (this.horizontalPageBreaks == null && horizontalCount > 0)
		{
			this.horizontalPageBreaks = [];
		}

		if (this.horizontalPageBreaks != null)
		{
			for (var i = 0; i <= horizontalCount; i++)
			{
				var pts = [new mxPoint(bounds2.x + (i + 1) * bounds.width, bounds2.y),
				           new mxPoint(bounds2.x + (i + 1) * bounds.width, bottom)];
				
				if (this.horizontalPageBreaks[i] != null)
				{
					this.horizontalPageBreaks[i].scale = 1;
					this.horizontalPageBreaks[i].points = pts;
					this.horizontalPageBreaks[i].redraw();
				}
				else
				{
					var pageBreak = new mxPolyline(pts, this.pageBreakColor, this.scale);
					pageBreak.dialect = this.dialect;
					pageBreak.isDashed = this.pageBreakDashed;
					pageBreak.addPipe = false;
					pageBreak.scale = scale;
					pageBreak.crisp = true;
					pageBreak.init(this.view.backgroundPane);
					pageBreak.redraw();
					
					this.horizontalPageBreaks[i] = pageBreak;
				}
			}
			
			for (var i = horizontalCount; i < this.horizontalPageBreaks.length; i++)
			{
				this.horizontalPageBreaks[i].destroy();
			}
			
			this.horizontalPageBreaks.splice(horizontalCount, this.horizontalPageBreaks.length - horizontalCount);
		}
		
		if (this.verticalPageBreaks == null && verticalCount > 0)
		{
			this.verticalPageBreaks = [];
		}
		
		if (this.verticalPageBreaks != null)
		{
			for (var i = 0; i <= verticalCount; i++)
			{
				var pts = [new mxPoint(bounds2.x, bounds2.y + (i + 1) * bounds.height),
				           new mxPoint(right, bounds2.y + (i + 1) * bounds.height)];
				
				if (this.verticalPageBreaks[i] != null)
				{
					this.verticalPageBreaks[i].scale = 1; //scale;
					this.verticalPageBreaks[i].points = pts;
					this.verticalPageBreaks[i].redraw();
				}
				else
				{
					var pageBreak = new mxPolyline(pts, this.pageBreakColor, scale);
					pageBreak.dialect = this.dialect;
					pageBreak.isDashed = this.pageBreakDashed;
					pageBreak.addPipe = false;
					pageBreak.scale = scale;
					pageBreak.crisp = true;
					pageBreak.init(this.view.backgroundPane);
					pageBreak.redraw();
		
					this.verticalPageBreaks[i] = pageBreak;
				}
			}
			
			for (var i = verticalCount; i < this.verticalPageBreaks.length; i++)
			{
				this.verticalPageBreaks[i].destroy();
			}
			
			this.verticalPageBreaks.splice(verticalCount, this.verticalPageBreaks.length - verticalCount);
		}
	};
	
	// Enables snapping to off-grid terminals for edge waypoints
	mxEdgeHandler.prototype.snapToTerminals = true;

	// Enables guides
	mxGraphHandler.prototype.guidesEnabled = true;

	// Disables removing relative children from parents
	var mxGraphHandlerShouldRemoveCellsFromParent = mxGraphHandler.prototype.shouldRemoveCellsFromParent;
	mxGraphHandler.prototype.shouldRemoveCellsFromParent = function(parent, cells, evt)
	{
		for (var i = 0; i < cells.length; i++)
		{
			if (this.graph.getModel().isVertex(cells[i]))
			{
				var geo = this.graph.getCellGeometry(cells[i]);
				
				if (geo != null && geo.relative)
				{
					return false;
				}
			}
		}
		
		return mxGraphHandlerShouldRemoveCellsFromParent.apply(this, arguments);
	};
	
	// Alt-move disables guides
	mxGuide.prototype.isEnabledForEvent = function(evt)
	{
		return !mxEvent.isAltDown(evt);
	};
	
	// Consumes click events for disabled menu items
	mxPopupMenuAddItem = mxPopupMenu.prototype.addItem;
	mxPopupMenu.prototype.addItem = function(title, image, funct, parent, iconCls, enabled)
	{
		var result = mxPopupMenuAddItem.apply(this, arguments);
		
		if (enabled != null && !enabled)
		{
			mxEvent.addListener(result, 'mousedown', function(evt)
			{
				mxEvent.consume(evt);
			});
		}
		
		return result;
	};
	
	
	// Experimental add/remove waypoints
	mxEdgeHandler.prototype.addEnabled = true;
	mxEdgeHandler.prototype.removeEnabled = true;

	// Selects descendants before children selection mode
	var graphHandlerGetInitialCellForEvent = mxGraphHandler.prototype.getInitialCellForEvent;
	mxGraphHandler.prototype.getInitialCellForEvent = function(me)
	{
		var model = this.graph.getModel();
		var psel = model.getParent(this.graph.getSelectionCell());
		var cell = graphHandlerGetInitialCellForEvent.apply(this, arguments);
		var parent = model.getParent(cell);
		
		if (psel == null || (psel != cell && psel != parent))
		{
			while (!this.graph.isCellSelected(cell) && !this.graph.isCellSelected(parent) &&
					model.isVertex(parent) && !this.graph.isValidRoot(parent))
			{
				cell = parent;
				parent = this.graph.getModel().getParent(cell);
			}
		}
		
		return cell;
	};
	
	// Selection is delayed to mouseup if child selected
	var graphHandlerIsDelayedSelection = mxGraphHandler.prototype.isDelayedSelection;
	mxGraphHandler.prototype.isDelayedSelection = function(cell)
	{
		var result = graphHandlerIsDelayedSelection.apply(this, arguments);
		var model = this.graph.getModel();
		var psel = model.getParent(this.graph.getSelectionCell());
		var parent = model.getParent(cell);
		
		if (psel == null || (psel != cell && psel != parent))
		{
			if (!this.graph.isCellSelected(cell) && model.isVertex(parent) && !this.graph.isValidRoot(parent))
			{
				result = true;
			}
		}
		
		return result;
	};
	
	// Delayed selection of parent group
	mxGraphHandler.prototype.selectDelayed = function(me)
	{
		var cell = me.getCell();
		
		if (cell == null)
		{
			cell = this.cell;
		}
		
		var model = this.graph.getModel();
		var parent = model.getParent(cell);
		
		while (this.graph.isCellSelected(cell) && model.isVertex(parent) && !this.graph.isValidRoot(parent))
		{
			cell = parent;
			parent = model.getParent(cell);
		}
		
		this.graph.selectCellForEvent(cell, me.getEvent());
	};

	// Returns last selected ancestor
	mxPanningHandler.prototype.getCellForPopupEvent = function(me)
	{
		var cell = me.getCell();
		var model = this.graph.getModel();
		var parent = model.getParent(cell);
		
		while (model.isVertex(parent) && !this.graph.isValidRoot(parent))
		{
			if (this.graph.isCellSelected(parent))
			{
				cell = parent;
			}
			
			parent = model.getParent(parent);
		}
		
		return cell;
	};
};

/**
 * Creates and returns a new undo manager.
 */
Editor.prototype.createUndoManager = function()
{
	var graph = this.graph;
	var undoMgr = new mxUndoManager();

    // Installs the command history
	var listener = function(sender, evt)
	{
		undoMgr.undoableEditHappened(evt.getProperty('edit'));
	};
	
	graph.getModel().addListener(mxEvent.UNDO, listener);
	graph.getView().addListener(mxEvent.UNDO, listener);

	// Keeps the selection in sync with the history
	var undoHandler = function(sender, evt)
	{
		var cand = graph.getSelectionCellsForChanges(evt.getProperty('edit').changes);
		var cells = [];
		
		for (var i = 0; i < cand.length; i++)
		{
			if (graph.view.getState(cand[i]) != null)
			{
				cells.push(cand[i]);
			}
		}
		
		graph.setSelectionCells(cells);
	};
	
	undoMgr.addListener(mxEvent.UNDO, undoHandler);
	undoMgr.addListener(mxEvent.REDO, undoHandler);

	return undoMgr;
};

/**
 * Overrides stencil registry to add dynamic loading.
 */
Editor.prototype.initStencilRegistry = function()
{
	mxStencilRegistry.packages = [];

	// Extends the default stencil registry to add dynamic loading
	mxStencilRegistry.getStencil = function(name)
	{
		var result = mxStencilRegistry.stencils[name];
		
		var parts = name.split('.');
		
		if (parts.length > 0 && parts[0] == 'mxgraph')
		{
			var tmp = parts[1];
			
			for (var i = 2; i < parts.length - 1; i++)
			{
				tmp += '/' + parts[i];
			}

			mxStencilRegistry.loadStencilSet(STENCIL_PATH + '/' + tmp + '.xml', null);

			// Tries again after all shapes for file have been registered
			result = mxStencilRegistry.stencils[name];
		}
		
		return result;
	};

	// Loads the given stencil set
	mxStencilRegistry.loadStencilSet = function(stencilFile, postStencilLoad, force)
	{
		force = (force != null) ? force : false;
		
		// Uses additional cache for detecting previous load attempts
		var installed = mxStencilRegistry.packages[stencilFile] != null;
		
		if (force || !installed)
		{
			mxStencilRegistry.packages[stencilFile] = 1;
			var req = mxUtils.load(stencilFile);
			var root = req.getDocumentElement();
			var shape = root.firstChild;
			var packageName = '';
			var name = root.getAttribute('name');
			
			if (name != null)
			{
				packageName = name + '.';
			}
			
			while (shape != null)
			{
				if (shape.nodeType == mxConstants.NODETYPE_ELEMENT)
				{
					name = shape.getAttribute('name');
					
					if (name != null)
					{
						var w = shape.getAttribute('w');
						var h = shape.getAttribute('h');
						
						w = (w == null) ? 80 : parseInt(w, 10);
						h = (h == null) ? 80 : parseInt(h, 10);
						
						packageName = packageName.toLowerCase();
						var stencilName = name.replace(/ /g,"_");
							
						if (!installed)
						{
							mxStencilRegistry.addStencil(packageName + stencilName.toLowerCase(), new mxStencil(shape));
						}
		
						if (postStencilLoad != null)
						{
							postStencilLoad(packageName, stencilName, name, w, h);
						}
					}
				}
				
				shape = shape.nextSibling;
			}
		}
	};

	// Loads default stencils
	mxStencilRegistry.loadStencilSet(STENCIL_PATH + '/general.xml');
};

/**
 * Class for asynchronously opening a new window and loading a file at the same
 * time. This acts as a bridge between the open dialog and the new editor.
 */
OpenFile = function(done)
{
	this.producer = null;
	this.consumer = null;
	this.done = done;
};

/**
 * Registers the editor from the new window.
 */
OpenFile.prototype.setConsumer = function(value)
{
	this.consumer = value;
	this.execute();
};

/**
 * Sets the data from the loaded file.
 */
OpenFile.prototype.setData = function(value, filename)
{
	this.data = value;
	this.filename = filename;
	this.execute();
};

/**
 * Displays an error message.
 */
OpenFile.prototype.error = function(msg)
{
	this.cancel();
	mxUtils.alert(msg);
};

/**
 * Consumes the data.
 */
OpenFile.prototype.execute = function()
{
	if (this.consumer != null && this.data != null)
	{
		this.consumer(this.data, this.filename);
		this.cancel();
	}
};

/**
 * Cancels the operation.
 */
OpenFile.prototype.cancel = function()
{
	if (this.done != null)
	{
		this.done();
	}
};