try to get a tray icon working

gui/griffon-app/lifecycle/Initialize.groovy

@@ -10,7 +10,9 @@ import com.muwire.gui.UISettings
 
 import javax.annotation.Nonnull
 import javax.inject.Inject
+import javax.swing.ImageIcon
 import javax.swing.JLabel
+import javax.swing.JPopupMenu
 import javax.swing.JTable
 import javax.swing.LookAndFeel
 import javax.swing.UIManager
@@ -20,7 +22,11 @@ import static griffon.util.GriffonApplicationUtils.isMacOSX
 import static groovy.swing.SwingBuilder.lookAndFeel
 
 import java.awt.Font
+import java.awt.MenuItem
+import java.awt.PopupMenu
+import java.awt.SystemTray
 import java.awt.Toolkit
+import java.awt.TrayIcon
 import java.util.logging.Level
 import java.util.logging.LogManager
 
@@ -43,6 +49,39 @@ class Initialize extends AbstractLifecycleHandler {
             }
         }
         
+        if (SystemTray.isSupported()) {
+            try {
+                def tray = SystemTray.getSystemTray()
+                def url = Initialize.class.getResource("/MuWire-32x32.png")
+                def image = new ImageIcon(url, "tray icon").getImage()
+                def popupMenu = new PopupMenu()
+                def trayIcon = new TrayIcon(image, "MuWire", popupMenu)
+
+
+                def exit = new MenuItem("Exit")
+                exit.addActionListener({
+                    Core core = application.getContext().get("core")
+                    if (core != null)
+                        core.shutdown()
+                    tray.remove(trayIcon)
+                    System.exit(0)
+                })
+
+                popupMenu.add(exit)
+                tray.add(trayIcon)
+                
+                
+                trayIcon.addActionListener({ e ->
+                    def mainFrame = application.getWindowManager().findWindow("main-frame")
+                    if (mainFrame != null)
+                        mainFrame.setVisible(true)
+                })
+                application.getContext().put("tray-icon", true)
+            } catch (Exception bad) {
+                log.log(Level.WARNING,"couldn't set tray icon",bad)
+            }
+        }
+        
         log.info "Loading home dir"
         def portableHome = System.getProperty("portable.home")
         def home = portableHome == null ?

gui/griffon-app/views/com/muwire/gui/MainFrameView.groovy

@@ -1,5 +1,6 @@
 package com.muwire.gui
 
+import griffon.core.GriffonApplication
 import griffon.core.artifact.GriffonView
 import griffon.core.env.Metadata
 import griffon.inject.MVCMember
@@ -11,6 +12,7 @@ import javax.swing.BorderFactory
 import javax.swing.Box
 import javax.swing.BoxLayout
 import javax.swing.JFileChooser
+import javax.swing.JFrame
 import javax.swing.JLabel
 import javax.swing.JMenuItem
 import javax.swing.JPopupMenu
@@ -54,6 +56,7 @@ class MainFrameView {
     @MVCMember @Nonnull
     MainFrameModel model
 
+    @Inject @Nonnull GriffonApplication application
     @Inject Metadata metadata
 
     def downloadsTable
@@ -64,10 +67,13 @@ class MainFrameView {
     UISettings settings
     
     void initUI() {
+        int closeOperation = application.getContext().get("tray-icon") ? JFrame.HIDE_ON_CLOSE : JFrame.EXIT_ON_CLOSE
+        
         settings = application.context.get("ui-settings")
         builder.with {
             application(size : [1024,768], id: 'main-frame',
             locationRelativeTo : null,
+            defaultCloseOperation : closeOperation,
             title: application.configuration['application.title'] + " " +
             metadata["application.version"] + " revision " + metadata["build.revision"],
             iconImage:   imageIcon('/MuWire-48x48.png').image,