UX fix

- Made high score dialog modal
- Added check for type mismatch when unserializing high scores
- Added remaining mines counter refresh on board reset

src/dev/kske/minesweeper/Board.java

@@ -87,6 +87,8 @@ public class Board extends JPanel {
 		activeTiles		= boardWidth * boardHeight;
 		flaggedTiles	= 0;
 
+		notifyFlaggedTilesEvent(new FlaggedTilesEvent(this, flaggedTiles));
+
 		// Initialize board
 		board = new Tile[boardWidth][boardHeight];
 		for (int i = 0; i < boardWidth; i++)

src/dev/kske/minesweeper/Minesweeper.java

@@ -48,15 +48,12 @@ public class Minesweeper {
 	 * Launch the application.
 	 */
 	public static void main(String[] args) {
-		EventQueue.invokeLater(new Runnable() {
-
-			public void run() {
-				try {
-					Minesweeper window = new Minesweeper();
-					window.mframe.setVisible(true);
-				} catch (Exception e) {
-					e.printStackTrace();
-				}
+		EventQueue.invokeLater(() -> {
+			try {
+				Minesweeper window = new Minesweeper();
+				window.mframe.setVisible(true);
+			} catch (Exception e) {
+				e.printStackTrace();
 			}
 		});
 	}
@@ -182,14 +179,20 @@ public class Minesweeper {
 		mframe.setJMenuBar(menubar);
 	}
 
-	@SuppressWarnings("unchecked")
+	@SuppressWarnings(
+		"unchecked"
+	)
 	private void loadScores() {
 		try (var in = new ObjectInputStream(new FileInputStream(scoresFile))) {
-			scores = (TreeSet<Score>) in.readObject();
+			Object obj = in.readObject();
+			if (obj instanceof TreeSet<?>) scores = (TreeSet<Score>) obj;
+			else throw new IOException("Serialized object has the wrong class.");
 		} catch (FileNotFoundException ex) {
 			scores = new TreeSet<>();
 		} catch (IOException | ClassNotFoundException ex) {
-			JOptionPane.showMessageDialog(mframe, "The score file seems to be corrupted. It will be replaced when closing the game.", "File error", JOptionPane.ERROR_MESSAGE);
+			JOptionPane.showMessageDialog(mframe,
+					"The score file seems to be corrupted. It will be replaced when closing the game.", "File error",
+					JOptionPane.ERROR_MESSAGE);
 			scores = new TreeSet<>();
 		}
 	}

src/dev/kske/minesweeper/ScoreDialog.java

@@ -27,6 +27,7 @@ public class ScoreDialog extends JDialog {
 	 * Create the dialog.
 	 */
 	public ScoreDialog(Set<Score> scores) {
+		setModal(true);
 		setBounds(100, 100, 450, 300);
 		setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
 		getContentPane().setLayout(new BorderLayout(0, 0));