Added background execution

src/main/java/envoy/client/ui/Startup.java

@@ -5,6 +5,7 @@ import java.io.IOException;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import javax.swing.JFrame;
 import javax.swing.JOptionPane;
 
 import envoy.client.Client;
@@ -84,7 +85,7 @@ public class Startup {
 					throw new EnvoyException("Could not enter offline mode: user name unknown");
 				client.setSender(clientUser);
 			} catch(Exception e2) {
-				JOptionPane.showMessageDialog(null, e1.toString(), "Client error", JOptionPane.ERROR_MESSAGE);
+				JOptionPane.showMessageDialog(null, e2.toString(), "Client error", JOptionPane.ERROR_MESSAGE);
 				System.exit(1);
 				return;
 			}
@@ -118,6 +119,9 @@ public class Startup {
 
 				try {
 					new StatusTrayIcon(chatWindow).show();
+					
+					// If the tray icon is supported, hide the chat window on close
+					chatWindow.setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
 				} catch (EnvoyException e) {
 					logger.warning("The StatusTrayIcon is not supported on this platform!");
 				}

src/main/java/envoy/client/ui/StatusTrayIcon.java

@@ -75,16 +75,15 @@ public class StatusTrayIcon implements EventHandler {
 		focusTarget.addWindowFocusListener(new WindowAdapter() {
 
 			@Override
-			public void windowGainedFocus(WindowEvent e) {
-				displayMessages = false;
-			}
+			public void windowGainedFocus(WindowEvent e) { displayMessages = false; }
 
 			@Override
-			public void windowLostFocus(WindowEvent e) {
-				displayMessages = true;
-			}
+			public void windowLostFocus(WindowEvent e) { displayMessages = true; }
 		});
 
+		// Show the window if the user clicks on the icon
+		trayIcon.addActionListener((evt) -> { focusTarget.setVisible(true); focusTarget.requestFocus(); });
+
 		// Start processing message events
 		EventBus.getInstance().register(this);
 	}