Prototype workaround 2

gistfile1.js

mxHierarchicalLayout.prototype.run = function(parent)
{
  // Separate out unconnected hierarchies
	var hierarchyVertices = [];
	var allVertexSet = [];

	if (this.roots == null && parent != null)
	{
		var filledVertexSet = Object();
		this.filterDescendants(parent, filledVertexSet);

		this.roots = [];
		var filledVertexSetEmpty = true;

		// Poor man's isSetEmpty
		for (var key in filledVertexSet)
		{
			if (filledVertexSet[key] != null)
			{
				filledVertexSetEmpty = false;
				break;
			}
		}

		while (!filledVertexSetEmpty)
		{
			var candidateRoots = this.findRoots(parent, filledVertexSet);
			
			// If the candidate root is an unconnected group cell, remove it from
			// the layout. We may need a custom set that holds such groups and forces
			// them to be processed for resizing and/or moving.
			

			for (var i = 0; i < candidateRoots.length; i++)
			{
				var vertexSet = Object();
				hierarchyVertices.push(vertexSet);

				this.traverse(candidateRoots[i], true, null, allVertexSet, vertexSet,
						hierarchyVertices, filledVertexSet);
			}

			for (var i = 0; i < candidateRoots.length; i++)
			{
				this.roots.push(candidateRoots[i]);
			}
			
			filledVertexSetEmpty = true;
			
			// Poor man's isSetEmpty
			for (var key in filledVertexSet)
			{
				if (filledVertexSet[key] != null)
				{
					filledVertexSetEmpty = false;
					break;
				}
			}
		}
	}
	else
	{
		// Find vertex set as directed traversal from roots

		for (var i = 0; i < this.roots.length; i++)
		{
			var vertexSet = Object();
			hierarchyVertices.push(vertexSet);

			this.traverse(this.roots[i], true, null, allVertexSet, vertexSet,
					hierarchyVertices, null);
		}
	}

	// Iterate through the result removing parents who have children in this layout
	
	// Perform a layout for each seperate hierarchy
	// Track initial coordinate x-positioning
	var initialX = 0;

	for (var i = 0; i < hierarchyVertices.length; i++)
	{
		var vertexSet = hierarchyVertices[i];
		var tmp = [];
		
		for (var key in vertexSet)
		{
			tmp.push(vertexSet[key]);
		}
		
		this.model = new mxGraphHierarchyModel(this, tmp, this.roots,
			parent, this.tightenToSource);

		this.cycleStage(parent);
		this.layeringStage();
		
		this.crossingStage(parent);
		initialX = this.placementStage(initialX, parent);
	}
};