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

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
   3  * in Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.diagram.handler;
  13
  14 import org.eclipse.core.commands.AbstractHandler;
  15 import org.eclipse.core.commands.ExecutionEvent;
  16 import org.eclipse.core.commands.ExecutionException;
  17 import org.eclipse.swt.widgets.Event;
  18 import org.eclipse.ui.IWorkbenchPart;
  19 import org.eclipse.ui.handlers.HandlerUtil;
  20 import org.simantics.g2d.canvas.ICanvasContext;
  21 import org.simantics.g2d.chassis.ICanvasChassis;
  22 import org.simantics.scenegraph.g2d.events.EventDebugPolicy;
  23 import org.simantics.scenegraph.g2d.events.EventQueue;
  24 import org.simantics.scenegraph.g2d.events.command.Command;
  25 import org.simantics.scenegraph.g2d.events.command.CommandEvent;
  26
  27 /**
  28  * A handler for the Eclipse Command framework that delegates ID of the command
  29  * that triggered the event to the {@link EventQueue} of the
  30  * {@link ICanvasContext} where the event occurred.
  31  */
  32 public class CanvasCommandDelegate extends AbstractHandler {
  33
  34     private final boolean DEBUG = EventDebugPolicy.CANVAS_COMMAND_DELEGATION;
  35
  36     @Override
  37     public Object execute(ExecutionEvent event) throws ExecutionException {
  38         Event e = ((Event)event.getTrigger());
  39         CommandEvent ce = new CommandEvent(null, e.time, new Command(event.getCommand().getId()));
  40
  41         if (DEBUG)
  42             System.out.println(getClass().getSimpleName() + ": trigger event = " + e + " for command " + ce.command);
  43
  44         if (e.widget instanceof ICanvasChassis) {
  45             ICanvasChassis chassis = (ICanvasChassis) e.widget;
  46             ICanvasContext canvas = chassis.getCanvasContext();
  47             if (canvas != null) {
  48                 if (DEBUG)
  49                     System.out.println(getClass().getSimpleName() + ": sending command " + event.getCommand().getId() + " to " + chassis);
  50                 canvas.getEventQueue().queueEvent( ce );
  51             }
  52         } else {
  53             ICanvasContext canvas = null;
  54             IWorkbenchPart part = HandlerUtil.getActiveEditor(event);
  55             if (part != null)
  56                 canvas = (ICanvasContext) part.getAdapter(ICanvasContext.class);
  57             if (canvas == null) {
  58                 part = HandlerUtil.getActivePart(event);
  59                 if (part != null)
  60                     canvas = (ICanvasContext) part.getAdapter(ICanvasContext.class);
  61             }
  62             if (canvas != null) {
  63                 if (DEBUG)
  64                     System.out.println(getClass().getSimpleName() + ": sending command " + event.getCommand().getId() + " to " + part);
  65                 canvas.getEventQueue().queueEvent(ce);
  66             }
  67         }
  68         return null;
  69     }
  70
  71 }