Loading ChatWindow in parallel to Client and LocalDB

Fixes #26

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

@@ -54,14 +54,9 @@ public class ChatWindow extends JFrame {
 	 * Initializes a {@link JFrame} with UI elements used to send and read messages
 	 * to different users.
 	 *
-	 * @param client  the {@link Client} used to send and receive messages
-	 * @param localDB the {@link LocalDB} used to manage stored messages and users
 	 * @since Envoy v0.1-alpha
 	 */
-	public ChatWindow(Client client, LocalDB localDB) {
+	public ChatWindow() {
-		this.client		= client;
-		this.localDB	= localDB;
-
 		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 		setBounds(100, 100, 600, 800);
 		setTitle("Envoy");
@@ -164,7 +159,7 @@ public class ChatWindow extends JFrame {
 		userList.setCellRenderer(new UserListRenderer());
 		userList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
 		userList.addListSelectionListener((listSelectionEvent) -> {
-			if (!listSelectionEvent.getValueIsAdjusting()) {
+			if (client != null && localDB != null && !listSelectionEvent.getValueIsAdjusting()) {
 				@SuppressWarnings("unchecked")
 				final JList<User>	selectedUserList	= (JList<User>) listSelectionEvent.getSource();
 				final User			user				= selectedUserList.getSelectedValue();
@@ -193,16 +188,12 @@ public class ChatWindow extends JFrame {
 		gbc_userList.anchor	= GridBagConstraints.PAGE_START;
 		gbc_userList.insets	= new Insets(space, space, space, space);
 
-		changeChatWindowColors(Settings.getInstance().getThemes().get(Settings.getInstance().getCurrentTheme()));
+		applyTheme(Settings.getInstance().getThemes().get(Settings.getInstance().getCurrentTheme()));
 
 		contentPane.add(userList, gbc_userList);
 		contentPane.revalidate();
 
-		EventBus.getInstance().register(ThemeChangeEvent.class, (evt) -> changeChatWindowColors((Theme) evt.get()));
+		EventBus.getInstance().register(ThemeChangeEvent.class, (evt) -> applyTheme((Theme) evt.get()));
-
-		loadUsersAndChats();
-
-		if (client.isOnline()) startSyncThread(Config.getInstance().getSyncTimeout());
 
 		contentPane.revalidate();
 	}
@@ -211,9 +202,9 @@ public class ChatWindow extends JFrame {
 	 * Used to immediately reload the ChatWindow when settings were changed.
 	 *
 	 * @param theme the theme to change colors into
-	 * @since Envoy v0.1-alpha
+	 * @since Envoy v0.2-alpha
 	 */
-	private void changeChatWindowColors(Theme theme) {
+	private void applyTheme(Theme theme) {
 		// contentPane
 		contentPane.setBackground(theme.getBackgroundColor());
 		contentPane.setForeground(theme.getUserNameColor());
@@ -334,4 +325,27 @@ public class ChatWindow extends JFrame {
 	 * Marks messages in the current chat as {@code READ}.
 	 */
 	private void readCurrentChat() { if (currentChat != null) { localDB.setMessagesToRead(currentChat); } }
+
+	/**
+	 * Sets the {@link Client} used by this {@link ChatWindow}. If the client is
+	 * online, the sync thread is started.
+	 *
+	 * @param client the {@link Client} used to send and receive messages
+	 */
+	public void setClient(Client client) {
+		this.client = client;
+		if (client.isOnline() && localDB != null) startSyncThread(Config.getInstance().getSyncTimeout());
+	}
+
+	/**
+	 * Sets the {@link LocalDB} used by this {@link ChatWindow}. After invoking this
+	 * method, users and chats will be loaded from the database into the GUI.
+	 *
+	 * @param localDB the {@link LocalDB} used to manage stored messages and users
+	 */
+	public void setLocalDB(LocalDB localDB) {
+		this.localDB = localDB;
+		loadUsersAndChats();
+		if (client != null && client.isOnline()) startSyncThread(Config.getInstance().getSyncTimeout());
+	}
 }

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

@@ -8,6 +8,7 @@ import java.util.logging.Logger;
 
 import javax.swing.JFrame;
 import javax.swing.JOptionPane;
+import javax.swing.SwingUtilities;
 
 import envoy.client.*;
 import envoy.client.util.EnvoyLog;
@@ -28,6 +29,8 @@ import envoy.schema.User;
  */
 public class Startup {
 
+	private static ChatWindow chatWindow;
+
 	private static final Logger logger = EnvoyLog.getLogger(Startup.class.getSimpleName());
 
 	/**
@@ -44,6 +47,8 @@ public class Startup {
 	public static void main(String[] args) {
 		Config config = Config.getInstance();
 
+		SwingUtilities.invokeLater(() -> chatWindow = new ChatWindow());
+
 		try {
 			// Load the configuration from client.properties first
 			config.load();
@@ -82,6 +87,8 @@ public class Startup {
 			return;
 		}
 
+		SwingUtilities.invokeLater(() -> chatWindow.setVisible(true));
+
 		// Acquire the client user (with ID) either from the server or from the local
 		// database, which triggers offline mode
 		Client client = new Client(config);
@@ -96,6 +103,10 @@ public class Startup {
 				User clientUser = localDB.getUsers().get(userName);
 				if (clientUser == null) throw new EnvoyException("Could not enter offline mode: user name unknown");
 				client.setSender(clientUser);
+				JOptionPane.showMessageDialog(null,
+						"A connection to the server could not be established. Starting in offline mode.",
+						"Connection error",
+						JOptionPane.WARNING_MESSAGE);
 			} catch (Exception e2) {
 				JOptionPane.showMessageDialog(null, e2.toString(), "Client error", JOptionPane.ERROR_MESSAGE);
 				System.exit(1);
@@ -125,8 +136,8 @@ public class Startup {
 
 		EventQueue.invokeLater(() -> {
 			try {
-				ChatWindow chatWindow = new ChatWindow(client, localDB);
+				chatWindow.setClient(client);
-				chatWindow.setVisible(true);
+				chatWindow.setLocalDB(localDB);
 
 				try {
 					new StatusTrayIcon(chatWindow).show();