您可能应该使用JComboBox允许用户在3个可用选项中进行选择。如果使用此JComboBox制作启动Jframe，则可以随后创建您的主游戏框架并将其值传递给JComboBox。
例如，您可以让JComboBox提供困难设置Easy，Medium和Hard的选项。在JButton上使用动作侦听器，从JComboBox获取选定的值，并将其转换为适合于minimax算法的int值。也就是说，通过1代表轻松，2代表中等，3代表艰苦。
接下来，更改您的ai类，以便将maxDepth放入构造函数中。然后，当实例化ai时，只需为其提供从前一帧传递来的值，就可以在正确的难度设置下创建所需的唯一ai。
编辑：
看来您设法完成了类似的工作，这真是太好了！为了对您有所帮助，我在下面提供了一个简短的示例，说明了如何进行此操作。请注意，我还对它进行了设置，以使您的SimpleAiPlayerHandler构造函数也采用一个int值来实例化maxDepth变量。您需要添加它。由于它使用的是我没有的类，因此我无法对其进行编译。但是，如果其他任何人需要做类似的事情，只需除去DifficultyListener中的所有内容，除了print语句和JComboBox遇到的困难的行，您就会发现它可以正常工作（并进行编译）。
import javax.swing.*;import java.awt.event.*;public class ChessSplash extends Jframe { private final JComboBox<Difficulty> difficultySetting; public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { @Override public void run() { ChessSplash gui = new ChessSplash(); gui.setVisible(true); } }); } public enum Difficulty { EASY(1, "Easy"), MEDIUM(2, "Medium"), HARD(3, "Hard"); private final int intValue; private final String stringValue; private Difficulty(int intValue, String stringValue) { this.intValue = intValue; this.stringValue = stringValue; } @Override public String toString() { return stringValue; } }; public ChessSplash() { super("Chess Game"); setDefaultCloseOperation(Jframe.EXIT_ON_CLOSE); difficultySetting = new JComboBox<>(Difficulty.values()); JButton startButton = new JButton("Start Game"); startButton.addActionListener(new DifficultyListener()); JPanel mainPanel = new JPanel(); add(mainPanel); mainPanel.add(difficultySetting); mainPanel.add(startButton); pack(); } private class DifficultyListener implements ActionListener { @Override public void actionPerformed(ActionEvent e) { //Declare AI SimpleAiPlayerHandler ai; //Declare and Instantiate Chess Game ChessGame chessGame = new ChessGame(); //Human Player is the Object chessGui ChessGui chessGui = new ChessGui(chessGame); //Assign Human Player to White chessGame.setPlayer(Piece.COLOR_WHITE, chessGui); //Get the selected difficulty setting Difficulty difficulty = (Difficulty)difficultySetting.getSelectedItem(); //Instantiate Computer AI pass it the maxDepth for use in the constructor ai = new SimpleAiPlayerHandler(difficulty.intValue, chessGame); //Assign Computer Player to Black chessGame.setPlayer(Piece.COLOR_BLACK, ai); //Demonstrate the enum combobox works System.out.println(difficulty.intValue); //Dispose of the splash Jframe ChessSplash.this.dispose(); //Start your game thread (I would probably do something to move this //onto the EDT if you're doing this is swing personally new Thread(chessGame).start(); } }}
