org.eclipse.linuxtools.lttng.ui/src/org/eclipse/linuxtools/lttng/ui/views/histogram/HistogramCanvasFocusListener.java

   1 /*******************************************************************************
   2  * Copyright (c) 2009 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  *   William Bourque - Initial API and implementation
  11  *
  12  * Modifications:
  13  * 2010-07-16 Yuriy Vashchuk - Heritage corrections.
  14  *******************************************************************************/
  15 package org.eclipse.linuxtools.lttng.ui.views.histogram;
  16
  17 import org.eclipse.swt.events.FocusEvent;
  18 import org.eclipse.swt.events.FocusListener;
  19
  20 /**
  21  * <b><u>HistogramCanvasFocusListener</u></b>
  22  * <p>
  23  * Implementation of a FocusListener for the need of the HistogramCanvas
  24  * <p>
  25  */
  26 public class HistogramCanvasFocusListener implements FocusListener {
  27
  28         private HistogramCanvas ourCanvas = null;
  29
  30         /**
  31          * HistogramCanvasFocusListener constructor
  32          *
  33          * @param newCanvas Related canvas
  34          */
  35         public HistogramCanvasFocusListener(HistogramCanvas newCanvas) {
  36                 ourCanvas = newCanvas;
  37         }
  38
  39         /**
  40          * Function that is called when the canvas get focus.<p>
  41          *
  42          * Redraw the screen to make sure everything is sane.
  43          *
  44          * @param event  The focus event generated.
  45          */
  46         @Override
  47         public void focusGained(FocusEvent event) {
  48                 ourCanvas.redrawAsynchronously();
  49         }
  50
  51         /**
  52          * Function that is called when the canvas loose focus.<p>
  53          *
  54          * Doesn't do anything yet...
  55          *
  56          * @param event  The focus event generated.
  57          */
  58         @Override
  59         public void focusLost(FocusEvent event) {
  60                 // Nothing to do yet
  61         }
  62
  63 }