Added events for changes of the game state and flagged tiles

src/dev/kske/minesweeper/Board.java

@@ -8,7 +8,9 @@ import java.awt.Graphics;
 import java.awt.Image;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.Random;
 
@@ -31,8 +33,9 @@ public class Board extends JPanel {
 	private GameState	gameState;
 	private int			mines, activeTiles, flaggedTiles;
 	private Tile[][]	board;
+	private BoardConfig	initialConfig;
 
-	private BoardConfig initialConfig;
+	private List<GameListener> listeners;
 
 	static {
 		icons = new HashMap<>();
@@ -45,6 +48,7 @@ public class Board extends JPanel {
 	public Board() {
 		// Not using a layout manager
 		super(null);
+		listeners = new ArrayList<>();
 		addMouseListener(new MouseAdapter() {
 
 			@Override
@@ -84,6 +88,7 @@ public class Board extends JPanel {
 			for (int j = 0; j < boardHeight; j++)
 				board[i][j] = new Tile();
 		initMines();
+		notifyFlaggedTilesEvent(new FlaggedTilesEvent(this, flaggedTiles));
 		repaint();
 	}
 
@@ -91,6 +96,18 @@ public class Board extends JPanel {
 		init(initialConfig);
 	}
 
+	public void registerGameListener(GameListener listener) {
+		listeners.add(listener);
+	}
+
+	private void notifyGameStateEvent(GameStateEvent evt) {
+		listeners.forEach(listener -> listener.onGameStateEvent(evt));
+	}
+
+	private void notifyFlaggedTilesEvent(FlaggedTilesEvent evt) {
+		listeners.forEach(listener -> listener.onFlaggedTilesEvent(evt));
+	}
+
 	@Override
 	public void paintComponent(Graphics g) {
 		super.paintComponent(g);
@@ -172,11 +189,21 @@ public class Board extends JPanel {
 			if (tile.isFlagged()) {
 				tile.setFlagged(false);
 				flaggedTiles--;
+				notifyFlaggedTilesEvent(new FlaggedTilesEvent(this, flaggedTiles));
 			}
 
 			// Test if the game is won or lost
-			if (tile.isMine()) gameState = GameState.LOST;
-			else if (mines == activeTiles) gameState = GameState.WON;
+			if (tile.isMine()) {
+				gameState = GameState.LOST;
+				repaint();
+				GameStateEvent evt = new GameStateEvent(this, gameState);
+				notifyGameStateEvent(evt);
+			} else if (mines == activeTiles) {
+				gameState = GameState.WON;
+				repaint();
+				GameStateEvent evt = new GameStateEvent(this, gameState);
+				notifyGameStateEvent(evt);
+			}
 
 			// Touch surrounding tiles when there are zero surrounding mines
 			else if (tile.getSurroundingMines() == 0)
@@ -198,6 +225,7 @@ public class Board extends JPanel {
 				tile.setFlagged(true);
 				flaggedTiles++;
 			}
+			notifyFlaggedTilesEvent(new FlaggedTilesEvent(this, flaggedTiles));
 			repaintTile(n, m);
 		}
 	}

src/dev/kske/minesweeper/CustomDialog.java

@@ -0,0 +1,63 @@
+package dev.kske.minesweeper;
+
+import java.awt.BorderLayout;
+import java.awt.FlowLayout;
+
+import javax.swing.JButton;
+import javax.swing.JDialog;
+import javax.swing.JPanel;
+import javax.swing.border.EmptyBorder;
+
+
+/**
+ * Project: <strong>Minesweeper</strong><br>
+ * File: <strong>CustomDialog.java</strong><br>
+ * Created: <strong>03.04.2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public class CustomDialog extends JDialog {
+
+	private static final long	serialVersionUID	= -4019516811065781434L;
+	private final JPanel mcontentPanel = new JPanel();
+
+	/**
+	 * Launch the application.
+	 */
+	public static void main(String[] args) {
+		try {
+			CustomDialog dialog = new CustomDialog();
+			dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
+			dialog.setVisible(true);
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+	}
+
+	/**
+	 * Create the dialog.
+	 */
+	public CustomDialog() {
+		setBounds(100, 100, 450, 300);
+		getContentPane().setLayout(new BorderLayout());
+		mcontentPanel.setLayout(new FlowLayout());
+		mcontentPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
+		getContentPane().add(mcontentPanel, BorderLayout.CENTER);
+		{
+			JPanel buttonPane = new JPanel();
+			buttonPane.setLayout(new FlowLayout(FlowLayout.RIGHT));
+			getContentPane().add(buttonPane, BorderLayout.SOUTH);
+			{
+				JButton okButton = new JButton("OK");
+				okButton.setActionCommand("OK");
+				buttonPane.add(okButton);
+				getRootPane().setDefaultButton(okButton);
+			}
+			{
+				JButton cancelButton = new JButton("Cancel");
+				cancelButton.setActionCommand("Cancel");
+				buttonPane.add(cancelButton);
+			}
+		}
+	}
+
+}

src/dev/kske/minesweeper/FlaggedTilesEvent.java

@@ -0,0 +1,27 @@
+package dev.kske.minesweeper;
+
+import java.util.EventObject;
+
+/**
+ * Project: <strong>Minesweeper</strong><br>
+ * File: <strong>FlaggedTilesEvent.java</strong><br>
+ * Created: <strong>03.04.2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public class FlaggedTilesEvent extends EventObject {
+
+	private static final long serialVersionUID = -5809857531886339312L;
+
+	private final Board	board;
+	private final int	flagged;
+
+	public FlaggedTilesEvent(Object source, int flagged) {
+		super(source);
+		board			= (Board) source;
+		this.flagged	= flagged;
+	}
+
+	public Board getBoard() { return board; }
+
+	public int getFlagged() { return flagged; }
+}

src/dev/kske/minesweeper/GameListener.java

@@ -0,0 +1,14 @@
+package dev.kske.minesweeper;
+
+/**
+ * Project: <strong>Minesweeper</strong><br>
+ * File: <strong>GameStateListener.java</strong><br>
+ * Created: <strong>03.04.2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public interface GameListener {
+
+	void onGameStateEvent(GameStateEvent evt);
+
+	void onFlaggedTilesEvent(FlaggedTilesEvent evt);
+}

src/dev/kske/minesweeper/GameStateEvent.java

@@ -0,0 +1,27 @@
+package dev.kske.minesweeper;
+
+import java.util.EventObject;
+
+/**
+ * Project: <strong>Minesweeper</strong><br>
+ * File: <strong>GameStateEvent.java</strong><br>
+ * Created: <strong>03.04.2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public class GameStateEvent extends EventObject {
+
+	private static final long	serialVersionUID	= -966111253980213845L;
+
+	private final Board		board;
+	private final GameState	gameState;
+
+	public GameStateEvent(Object source, GameState gameState) {
+		super(source);
+		board			= (Board) source;
+		this.gameState	= gameState;
+	}
+
+	public Board getBoard() { return board; }
+
+	public GameState getGameState() { return gameState; }
+}

src/dev/kske/minesweeper/Minesweeper.java

@@ -2,14 +2,18 @@ package dev.kske.minesweeper;
 
 import java.awt.BorderLayout;
 import java.awt.EventQueue;
+import java.awt.FlowLayout;
 import java.awt.event.KeyEvent;
 
 import javax.swing.JButton;
 import javax.swing.JFrame;
+import javax.swing.JLabel;
 import javax.swing.JMenu;
 import javax.swing.JMenuBar;
 import javax.swing.JMenuItem;
 import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.SwingConstants;
 
 /**
  * Project: <strong>Minesweeper</strong><br>
@@ -68,9 +72,38 @@ public class Minesweeper {
 		mframe.getContentPane().setLayout(new BorderLayout(0, 0));
 		mframe.getContentPane().add(board, BorderLayout.CENTER);
 
+
+		JPanel headerPanel = new JPanel();
+		mframe.getContentPane().add(headerPanel, BorderLayout.NORTH);
+		headerPanel.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
+
+		JLabel lblRemainingMines = new JLabel("Remaining Mines:");
+		lblRemainingMines.setHorizontalAlignment(SwingConstants.LEFT);
+		headerPanel.add(lblRemainingMines);
+
+		board.registerGameListener(new GameListener() {
+
+			@Override
+			public void onGameStateEvent(GameStateEvent evt) {
+				switch (evt.getGameState()) {
+					case LOST:
+						JOptionPane.showMessageDialog(mframe, "Game lost!");
+						break;
+					case WON:
+						JOptionPane.showMessageDialog(mframe, "Game won!");
+				}
+			}
+
+			@Override
+			public void onFlaggedTilesEvent(FlaggedTilesEvent evt) {
+				lblRemainingMines.setText("Remaining Mines: " + (evt.getBoard().getMines() - evt.getFlagged()));
+				mframe.pack();
+			}
+		});
+
 		JButton btnRestart = new JButton("Restart");
+		headerPanel.add(btnRestart);
 		btnRestart.addActionListener((evt) -> board.reset());
-		mframe.getContentPane().add(btnRestart, BorderLayout.NORTH);
 		mframe.pack();
 	}