<!--
  Copyright (c) 2006-2013, JGraph Ltd
  
  Clipboard example for mxGraph. This example demonstrates using the
  clipboard for providing cross-tab and cross-browser copy and paste.
-->
<html>
<head>
	<title>Clipboard 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 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
			{
				// Disables the built-in context menu
				mxEvent.disableContextMenu(container);
				
				// Creates the graph inside the given container
				var graph = new mxGraph(container);

				// Public helper method for shared clipboard.
				mxClipboard.cellsToString = function(cells)
				{
					var codec = new mxCodec();
					var model = new mxGraphModel();
					var parent = model.getChildAt(model.getRoot(), 0);
					
					for (var i = 0; i < cells.length; i++)
					{
						model.add(parent, cells[i]);
					}

					return mxUtils.getXml(codec.encode(model));
				};

				// Focused but invisible textarea during control or meta key events
				var textInput = document.createElement('textarea');
				mxUtils.setOpacity(textInput, 0);
				textInput.style.width = '1px';
				textInput.style.height = '1px';
				var restoreFocus = false;
				var gs = graph.gridSize;
				var lastPaste = null;
				var dx = 0;
				var dy = 0;

				// Workaround for no copy event in IE/FF if empty
				textInput.value = ' ';
			
				// Shows a textare when control/cmd is pressed to handle native clipboard actions
				mxEvent.addListener(document, 'keydown', function(evt)
				{
					// No dialog visible
					var source = mxEvent.getSource(evt);
					
					if (graph.isEnabled() && !graph.isMouseDown && !graph.isEditing() && source.nodeName != 'INPUT')
					{
						if (evt.keyCode == 224 /* FF */ || (!mxClient.IS_MAC && evt.keyCode == 17 /* Control */) || (mxClient.IS_MAC && evt.keyCode == 91 /* Meta */))
						{
							// Cannot use parentNode for check in IE
							if (!restoreFocus)
							{
								// Avoid autoscroll but allow handling of events
								textInput.style.position = 'absolute';
								textInput.style.left = (graph.container.scrollLeft + 10) + 'px';
								textInput.style.top = (graph.container.scrollTop + 10) + 'px';
								graph.container.appendChild(textInput);

								restoreFocus = true;
								textInput.focus();
								textInput.select();
							}
						}
					}
				});
				
				// Restores focus on graph container and removes text input from DOM
				mxEvent.addListener(document, 'keyup', function(evt)
				{
					if (restoreFocus && (evt.keyCode == 224 /* FF */ || evt.keyCode == 17 /* Control */ ||
						evt.keyCode == 91 /* Meta */))
					{
						restoreFocus = false;
						
						if (!graph.isEditing())
						{
							graph.container.focus();
						}
						
						textInput.parentNode.removeChild(textInput);
					}
				});
				
				// Inserts the XML for the given cells into the text input for copy
				var copyCells = function(graph, cells)
				{
					if (cells.length > 0)
					{
						var clones = graph.cloneCells(cells);
						
						// Checks for orphaned relative children and makes absolute
						for (var i = 0; i < clones.length; i++)
						{
							var state = graph.view.getState(cells[i]);
							
							if (state != null)
							{
								var geo = graph.getCellGeometry(clones[i]);
								
								if (geo != null && geo.relative)
								{
									geo.relative = false;
									geo.x = state.x / state.view.scale - state.view.translate.x;
									geo.y = state.y / state.view.scale - state.view.translate.y;
								}
							}
						}
						
						textInput.value = mxClipboard.cellsToString(clones);
					}
					
					textInput.select();
					lastPaste = textInput.value;
				};
				
				// Handles copy event by putting XML for current selection into text input
				mxEvent.addListener(textInput, 'copy', mxUtils.bind(this, function(evt)
				{
					if (graph.isEnabled() && !graph.isSelectionEmpty())
					{
						copyCells(graph, mxUtils.sortCells(graph.model.getTopmostCells(graph.getSelectionCells())));
						dx = 0;
						dy = 0;
					}
				}));
				
				// Handles cut event by removing cells putting XML into text input
				mxEvent.addListener(textInput, 'cut', mxUtils.bind(this, function(evt)
				{
					if (graph.isEnabled() && !graph.isSelectionEmpty())
					{
						copyCells(graph, graph.removeCells());
						dx = -gs;
						dy = -gs;
					}
				}));
				
				// Merges XML into existing graph and layers
				var importXml = function(xml, dx, dy)
				{
					dx = (dx != null) ? dx : 0;
					dy = (dy != null) ? dy : 0;
					var cells = []

					try
					{
						var doc = mxUtils.parseXml(xml);
						var node = doc.documentElement;
						
						if (node != null)
						{
							var model = new mxGraphModel();
							var codec = new mxCodec(node.ownerDocument);
							codec.decode(node, model);
							
							var childCount = model.getChildCount(model.getRoot());
							var targetChildCount = graph.model.getChildCount(graph.model.getRoot());
							
							// Merges existing layers and adds new layers
							graph.model.beginUpdate();
							try
							{
								for (var i = 0; i < childCount; i++)
								{
									var parent = model.getChildAt(model.getRoot(), i);
									
									// Adds cells to existing layers if not locked
									if (targetChildCount > i)
									{
										// Inserts into active layer if only one layer is being pasted
										var target = (childCount == 1) ? graph.getDefaultParent() : graph.model.getChildAt(graph.model.getRoot(), i);
										
										if (!graph.isCellLocked(target))
										{								
											var children = model.getChildren(parent);
											cells = cells.concat(graph.importCells(children, dx, dy, target));
										}
									}
									else
									{
										// Delta is non cascading, needs separate move for layers
										parent = graph.importCells([parent], 0, 0, graph.model.getRoot())[0];
										var children = graph.model.getChildren(parent);
										graph.moveCells(children, dx, dy);
										cells = cells.concat(children);
									}
								}
							}
							finally
							{
								graph.model.endUpdate();
							}
						}
					}
					catch (e)
					{
						alert(e);
						throw e;
					}
					
					return cells;
				};
				
				// Parses and inserts XML into graph
				var pasteText = function(text)
				{
					var xml = mxUtils.trim(text);
					var x = graph.container.scrollLeft / graph.view.scale - graph.view.translate.x;
					var y = graph.container.scrollTop / graph.view.scale - graph.view.translate.y;
					
					if (xml.length > 0)
					{
						if (lastPaste != xml)
						{
							lastPaste = xml;
							dx = 0;
							dy = 0;
						}
						else
						{
							dx += gs;
							dy += gs;
						}
								
						// Standard paste via control-v
						if (xml.substring(0, 14) == '<mxGraphModel>')
						{
							graph.setSelectionCells(importXml(xml, dx, dy));
							graph.scrollCellToVisible(graph.getSelectionCell());
						}
					}
				};
				
				// Cross-browser function to fetch text from paste events
				var extractGraphModelFromEvent = function(evt)
				{
					var data = null;
					
					if (evt != null)
					{
						var provider = (evt.dataTransfer != null) ? evt.dataTransfer : evt.clipboardData;
						
						if (provider != null)
						{
							if (document.documentMode == 10 || document.documentMode == 11)
							{
								data = provider.getData('Text');
							}
							else
							{
								data = (mxUtils.indexOf(provider.types, 'text/html') >= 0) ? provider.getData('text/html') : null;
							
								if (mxUtils.indexOf(provider.types, 'text/plain' && (data == null || data.length == 0)))
								{
									data = provider.getData('text/plain');
								}
							}		
						}
					}
					
					return data;
				};

				// Handles paste event by parsing and inserting XML
				mxEvent.addListener(textInput, 'paste', function(evt)
				{
					// Clears existing contents before paste - should not be needed
					// because all text is selected, but doesn't hurt since the
					// actual pasting of the new text is delayed in all cases.
					textInput.value = '';

					if (graph.isEnabled())
					{
						var xml = extractGraphModelFromEvent(evt);

						if (xml != null && xml.length > 0)
						{
							pasteText(xml);
						}
						else
						{
							// Timeout for new value to appear
							window.setTimeout(mxUtils.bind(this, function()
							{
								pasteText(textInput.value);
							}), 0);
						}
					}
		
					textInput.select();
				});

				// Enables rubberband selection
				new mxRubberband(graph);
				
				// 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, '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="position:relative;overflow:hidden;width:321px;height:241px;background:url('editors/images/grid.gif');cursor:default;">
	</div>
</body>
</html>