org.eclipse.linuxtools.lttng.ui/src/org/eclipse/linuxtools/lttng/ui/views/control/handlers/BaseNodeHandler.java

   1 /**********************************************************************
   2  * Copyright (c) 2012 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Bernd Hufmann - Initial API and implementation
  11  **********************************************************************/
  12 package org.eclipse.linuxtools.lttng.ui.views.control.handlers;
  13
  14 import org.eclipse.core.commands.AbstractHandler;
  15 import org.eclipse.jface.viewers.ISelection;
  16 import org.eclipse.jface.viewers.StructuredSelection;
  17 import org.eclipse.linuxtools.lttng.ui.views.control.ControlView;
  18 import org.eclipse.linuxtools.lttng.ui.views.control.model.impl.TargetNodeComponent;
  19 import org.eclipse.ui.IWorkbenchPage;
  20 import org.eclipse.ui.IWorkbenchPart;
  21 import org.eclipse.ui.IWorkbenchWindow;
  22 import org.eclipse.ui.PlatformUI;
  23
  24 /**
  25  * <b><u>BaseNodeHandler</u></b>
  26  * <p>
  27  * Command handler implementation to delete a target host.
  28  * </p>
  29  */
  30 abstract public class BaseNodeHandler extends AbstractHandler {
  31
  32     // ------------------------------------------------------------------------
  33     // Attributes
  34     // ------------------------------------------------------------------------
  35     /**
  36      * The target node component the command is to be executed on.
  37      */
  38     protected TargetNodeComponent fTargetNode = null;
  39
  40     // ------------------------------------------------------------------------
  41     // Constructors
  42     // ------------------------------------------------------------------------
  43
  44     // ------------------------------------------------------------------------
  45     // Accessors
  46     // ------------------------------------------------------------------------
  47     public TargetNodeComponent getTargetNode() {
  48         return fTargetNode;
  49     }
  50
  51     // ------------------------------------------------------------------------
  52     // Operations
  53     // ------------------------------------------------------------------------
  54     /*
  55      * (non-Javadoc)
  56      * @see org.eclipse.core.commands.AbstractHandler#isEnabled()
  57      */
  58     @Override
  59     public boolean isEnabled() {
  60         fTargetNode = null;
  61
  62         // Check if we are closing down
  63         IWorkbenchWindow window = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
  64         if (window == null) {
  65             return false;
  66         }
  67
  68         // Check if we are in the Project View
  69         IWorkbenchPage page = window.getActivePage();
  70         if (page == null) {
  71             return false;
  72         }
  73
  74         IWorkbenchPart part = page.getActivePart();
  75         if (!(part instanceof ControlView)) {
  76             return false;
  77         }
  78
  79         // Check if a project is selected
  80         ISelection selection = page.getSelection(ControlView.ID);
  81         if (selection instanceof StructuredSelection) {
  82             Object element = ((StructuredSelection) selection).getFirstElement();
  83             fTargetNode = (element instanceof TargetNodeComponent) ? (TargetNodeComponent) element : null;
  84         }
  85         return fTargetNode != null;
  86     }
  87 }