sch_test/mxclient/js/io/mxGraphViewCodec.js

/**
 * Copyright (c) 2006-2015, JGraph Ltd
 * Copyright (c) 2006-2015, Gaudenz Alder
 */
mxCodecRegistry.register(function()
{
	/**
	 * Class: mxGraphViewCodec
	 *
	 * Custom encoder for <mxGraphView>s. This class is created
	 * and registered dynamically at load time and used implicitly via
	 * <mxCodec> and the <mxCodecRegistry>. This codec only writes views
	 * into a XML format that can be used to create an image for
	 * the graph, that is, it contains absolute coordinates with
	 * computed perimeters, edge styles and cell styles.
	 */
	var codec = new mxObjectCodec(new mxGraphView());

	/**
	 * Function: encode
	 *
	 * Encodes the given <mxGraphView> using <encodeCell>
	 * starting at the model's root. This returns the
	 * top-level graph node of the recursive encoding.
	 */
	codec.encode = function(enc, view)
	{
		return this.encodeCell(enc, view,
			view.graph.getModel().getRoot());
	};

	/**
	 * Function: encodeCell
	 *
	 * Recursively encodes the specifed cell. Uses layer
	 * as the default nodename. If the cell's parent is
	 * null, then graph is used for the nodename. If
	 * <mxGraphModel.isEdge> returns true for the cell,
	 * then edge is used for the nodename, else if
	 * <mxGraphModel.isVertex> returns true for the cell,
	 * then vertex is used for the nodename.
	 *
	 * <mxGraph.getLabel> is used to create the label
	 * attribute for the cell. For graph nodes and vertices
	 * the bounds are encoded into x, y, width and height.
	 * For edges the points are encoded into a points
	 * attribute as a space-separated list of comma-separated
	 * coordinate pairs (eg. x0,y0 x1,y1 ... xn,yn). All
	 * values from the cell style are added as attribute
	 * values to the node. 
	 */
	codec.encodeCell = function(enc, view, cell)
	{
		var model = view.graph.getModel();
		var state = view.getState(cell);
		var parent = model.getParent(cell);
		
		if (parent == null || state != null)
		{
			var childCount = model.getChildCount(cell);
			var geo = view.graph.getCellGeometry(cell);
			var name = null;
			
			if (parent == model.getRoot())
			{
				name = 'layer';
			}
			else if (parent == null)
			{
				name = 'graph';
			}
			else if (model.isEdge(cell))
			{
				name = 'edge';
			}
			else if (childCount > 0 && geo != null)
			{
				name = 'group';
			}
			else if (model.isVertex(cell))
			{
				name = 'vertex';
			}
			
			if (name != null)
			{
				var node = enc.document.createElement(name);
				var lab = view.graph.getLabel(cell);
				
				if (lab != null)
				{
					node.setAttribute('label', view.graph.getLabel(cell));
					
					if (view.graph.isHtmlLabel(cell))
					{
						node.setAttribute('html', true);
					}
				}
		
				if (parent == null)
				{
					var bounds = view.getGraphBounds();
					
					if (bounds != null)
					{
						node.setAttribute('x', Math.round(bounds.x));
						node.setAttribute('y', Math.round(bounds.y));
						node.setAttribute('width', Math.round(bounds.width));
						node.setAttribute('height', Math.round(bounds.height));
					}
					
					node.setAttribute('scale', view.scale);
				}
				else if (state != null && geo != null)
				{
					// Writes each key, value in the style pair to an attribute
				    for (var i in state.style)
				    {
				    	var value = state.style[i];
		
				    	// Tries to turn objects and functions into strings
					    if (typeof(value) == 'function' &&
							typeof(value) == 'object')
						{
					    	value = mxStyleRegistry.getName(value);
				        }
				    	
				    	if (value != null &&
				    		typeof(value) != 'function' &&
							typeof(value) != 'object')
						{
							node.setAttribute(i, value);
				        }
				    }
				    
					var abs = state.absolutePoints;
					
					// Writes the list of points into one attribute
					if (abs != null && abs.length > 0)
					{
						var pts = Math.round(abs[0].x) + ',' + Math.round(abs[0].y);
		
						for (var i=1; i<abs.length; i++)
						{
							pts += ' ' + Math.round(abs[i].x) + ',' +
								Math.round(abs[i].y);
						}
		
						node.setAttribute('points', pts);
					}
					
					// Writes the bounds into 4 attributes
					else
					{
						node.setAttribute('x', Math.round(state.x));
						node.setAttribute('y', Math.round(state.y));
						node.setAttribute('width', Math.round(state.width));
						node.setAttribute('height', Math.round(state.height));				
					}
		
					var offset = state.absoluteOffset;
					
					// Writes the offset into 2 attributes
					if (offset != null)
					{
						if (offset.x != 0)
						{
							node.setAttribute('dx', Math.round(offset.x));
						}
						
						if (offset.y != 0)
						{
							node.setAttribute('dy', Math.round(offset.y));
						}
					}
				}
		
				for (var i=0; i<childCount; i++)
				{
					var childNode = this.encodeCell(enc,
							view, model.getChildAt(cell, i));
					
					if (childNode != null)
					{
						node.appendChild(childNode);
					}
				}
			}
		}
		
		return node;
	};

	// Returns the codec into the registry
	return codec;

}());