worldwinddemo/StatusBar.java

   1 /*
   2 Copyright (C) 2001, 2006 United States Government
   3 as represented by the Administrator of the
   4 National Aeronautics and Space Administration.
   5 All Rights Reserved.
   6 */
   7 package worldwinddemo;
   8
   9 import gov.nasa.worldwind.*;
  10 import gov.nasa.worldwind.geom.*;
  11
  12 import javax.swing.*;
  13 import java.awt.event.*;
  14
  15 /**
  16  * @author tag
  17  * @version $Id: StatusBar.java 1764 2007-05-07 20:01:57Z tgaskins $
  18  */
  19 public class StatusBar extends JPanel implements PositionListener
  20 {
  21     private WorldWindow eventSource;
  22     private final JLabel latDisplay = new JLabel("");
  23     private final JLabel lonDisplay = new JLabel("Off globe");
  24     private final JLabel eleDisplay = new JLabel("");
  25
  26     public StatusBar()
  27     {
  28         super(new java.awt.GridLayout(1, 0));
  29
  30         final JLabel heartBeat = new JLabel("Downloading");
  31
  32         latDisplay.setHorizontalAlignment(SwingConstants.CENTER);
  33         lonDisplay.setHorizontalAlignment(SwingConstants.CENTER);
  34         eleDisplay.setHorizontalAlignment(SwingConstants.CENTER);
  35
  36         this.add(new JLabel("")); // dummy label to visually balance with heartbeat
  37         this.add(latDisplay);
  38         this.add(lonDisplay);
  39         this.add(eleDisplay);
  40         this.add(heartBeat);
  41
  42         heartBeat.setHorizontalAlignment(SwingConstants.CENTER);
  43         heartBeat.setForeground(new java.awt.Color(255, 0, 0, 0));
  44
  45         Timer downloadTimer = new Timer(50, new ActionListener()
  46         {
  47             public void actionPerformed(java.awt.event.ActionEvent actionEvent)
  48             {
  49
  50                 java.awt.Color color = heartBeat.getForeground();
  51
  52                 int alpha = color.getAlpha();
  53
  54                 if (WorldWind.retrievalService().hasActiveTasks())
  55                 {
  56                     if (alpha == 255)
  57                         alpha = 255;
  58                     else
  59                         alpha = alpha < 16 ? 16 : Math.min(255, alpha + 20);
  60                 }
  61                 else
  62                 {
  63                     alpha = Math.max(0, alpha - 20);
  64                 }
  65                 heartBeat.setForeground(new java.awt.Color(255, 0, 0, alpha));
  66             }
  67         });
  68         downloadTimer.start();
  69     }
  70
  71     public void setEventSource(WorldWindow newEventSource)
  72     {
  73         if (this.eventSource != null)
  74             this.eventSource.removePositionListener(this);
  75
  76         if (newEventSource != null)
  77             newEventSource.addPositionListener(this);
  78
  79         this.eventSource = newEventSource;
  80     }
  81
  82     public void moved(PositionEvent event)
  83     {
  84         this.handleCursorPositionChange(event);
  85     }
  86
  87     public WorldWindow getEventSource()
  88     {
  89         return this.eventSource;
  90     }
  91
  92     private void handleCursorPositionChange(PositionEvent event)
  93     {
  94         Position newPos = (Position) event.getPosition();
  95         if (newPos != null)
  96         {
  97             String las = String.format("Latitude %7.3f\u00B0",
  98                 newPos.getLatitude().getDegrees());
  99             String los = String.format("Longitude %7.3f\u00B0",
 100                 newPos.getLongitude().getDegrees());
 101             String els = String.format("Elevation %7d meters", (int) newPos.getElevation());
 102             latDisplay.setText(las);
 103             lonDisplay.setText(los);
 104             eleDisplay.setText(els);
 105         }
 106         else
 107         {
 108             latDisplay.setText("");
 109             lonDisplay.setText("Off globe");
 110             eleDisplay.setText("");
 111         }
 112     }
 113 }