bundles/org.simantics.diagram/src/org/simantics/diagram/handler/ExpandSelectionHandler.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
   3  * in Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.diagram.handler;\r
  13 \r
  14 import java.util.Set;\r
  15 \r
  16 import org.eclipse.jface.action.IStatusLineManager;\r
  17 import org.eclipse.swt.widgets.Display;\r
  18 import org.simantics.g2d.canvas.impl.DependencyReflection.Dependency;\r
  19 import org.simantics.g2d.diagram.participant.AbstractDiagramParticipant;\r
  20 import org.simantics.g2d.diagram.participant.Selection;\r
  21 import org.simantics.g2d.element.IElement;\r
  22 import org.simantics.g2d.utils.TopologicalSelectionExpander;\r
  23 import org.simantics.scenegraph.g2d.events.EventHandlerReflection.EventHandler;\r
  24 import org.simantics.scenegraph.g2d.events.command.CommandEvent;\r
  25 import org.simantics.scenegraph.g2d.events.command.Commands;\r
  26 \r
  27 /**\r
  28  * This handler responds to the EXPAND_SELECTION command. It attempts to expand\r
  29  * the current selection for pointer 0, meaning {@link Selection#SELECTION0}.\r
  30  * \r
  31  * @see TopologicalSelectionExpander\r
  32  * @see Selection the current diagram selection source\r
  33  * \r
  34  * @author Tuukka Lehtonen\r
  35  */\r
  36 public class ExpandSelectionHandler extends AbstractDiagramParticipant {\r
  37 \r
  38         private final IStatusLineManager statusLine;\r
  39         \r
  40     @Dependency Selection selection;\r
  41 \r
  42     public ExpandSelectionHandler(IStatusLineManager statusLine) {\r
  43         this.statusLine = statusLine;\r
  44     }\r
  45     \r
  46     @EventHandler(priority = 0)\r
  47     public boolean handleExpand(CommandEvent event) {\r
  48         if (Commands.EXPAND_SELECTION.equals( event.command )) {\r
  49             return expandSelection(0);\r
  50         }\r
  51         return false;\r
  52     }\r
  53 \r
  54     /**\r
  55      * @param selectionId the id of the selection to expand\r
  56      * @return <code>true</code> if the selection changed as a result of the\r
  57      *         expansion, <code>false</code> if not\r
  58      */\r
  59     public boolean expandSelection(int selectionId) {\r
  60         Set<IElement> start = selection.getSelection(selectionId);\r
  61         TopologicalSelectionExpander expander = new TopologicalSelectionExpander(diagram, start);\r
  62         final Set<IElement> expanded = expander.expandedIfChanged();\r
  63         if (expanded == null)\r
  64             return false;\r
  65         selection.setSelection(selectionId, expanded);\r
  66         if(statusLine != null) {\r
  67                 Display.getDefault().asyncExec(new Runnable() {\r
  68 \r
  69                                 @Override\r
  70                                 public void run() {\r
  71                                 statusLine.setMessage("Expanded selection to include " + expanded.size() + " (from " + diagram.getElements().size() + ") items.");\r
  72                                 }\r
  73                         \r
  74                 });\r
  75         }\r
  76         return true;\r
  77     }\r
  78 \r
  79 }\r