Question

我基本上用AI和所有人制作一个tic tac toe游戏，我的系统是绘制按钮，并为每个按钮分配一个布尔值，如果它被分配给它，则为真。由X拍摄，如果是空的，则为假。它绘制了正确的大小和布局，除了在我的动作监听器中，它给了我错误：

编辑：删除决赛，仍然给出错误

＆＃34;无法分配最终的局部变量，因为它是在一个中定义的封闭式。＆＃34;

在将按钮文本分配给＆＃39; x＆＃39;后，我将布尔值更改为true。

package myClass;
import java.awt.Dimension;
import java.awt.GridLayout;

import javax.swing.JButton;
import javax.swing.JFrame;

public class mainClass {

    public static void main(String[] args) {
        //create window
        JFrame mainWindow = new JFrame("Tic Tac Toe");
        //properties of mainWindow
        mainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        mainWindow.setSize(600, 600); // buttons will fill entirely, 200x200 buttons
        mainWindow.setLayout(new GridLayout(3, 3));

        //create buttons
        JButton topLeft = new JButton("");
        JButton topMid = new JButton("");
        JButton topRight = new JButton("");
        JButton midLeft = new JButton("");
        JButton midMid = new JButton("");
        JButton midRight = new JButton("");
        JButton botLeft = new JButton("");
        JButton botMid = new JButton("");
        JButton botRight = new JButton("");


        //checker for if the button already has a character
boolean tmid = false;
boolean tright = false;
boolean mleft = false;
boolean mmid = false;
boolean mright = false;
boolean bleft = false;
boolean bmid = false;
boolean bright = false;

        //button properties
        Dimension buttonSize = new Dimension(200,200);
        topLeft.setSize(buttonSize);
        topMid.setSize(buttonSize);
        topRight.setSize(buttonSize);
        midLeft.setSize(buttonSize);
        midMid.setSize(buttonSize);
        midRight.setSize(buttonSize);
        botLeft.setSize(buttonSize);
        botMid.setSize(buttonSize);
        botRight.setSize(buttonSize);

        //Action listener
        topLeft.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(tleft == false){
                topLeft.setText("X");
                tleft = true;
            }   
            }
        });
        topMid.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(tmid == false){
                topMid.setText("X");
                tmid = true;
            }   
            }
        });
        topRight.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(tright == false){
                topRight.setText("X");
                tright = true;
            }   
            }
        });
        midLeft.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(mleft == false){
                midLeft.setText("X");
                mleft = true;
            }   
            }
        });
        midMid.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(mmid == false){
                midMid.setText("X");
                mmid = true;
            }   
            }
        });
        midRight.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(mright == false){
                midRight.setText("X");
                mright = true;
            }   
            }
        });
        botLeft.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(bleft == false){
                botLeft.setText("X");
                bleft = true;
            }   
            }
        });
        botMid.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(bmid == false){
                botMid.setText("X");
                bmid = true;
            }   
            }
        });
        botRight.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
            if(bright == false){
                botRight.setText("X");
                bright = true;
            }   
            }
        });




        //draw components
        mainWindow.add(topLeft);
        mainWindow.add(topMid);
        mainWindow.add(topRight);
        mainWindow.add(midLeft);
        mainWindow.add(midMid);
        mainWindow.add(midRight);
        mainWindow.add(botLeft);
        mainWindow.add(botMid);
        mainWindow.add(botRight);

        mainWindow.setVisible(true); // draw it
    }


}

Answer 1

有两个问题。一，你无法修改最终变量。二，必须使用final变量才能在监听器中使用范围。此代码需要严格的重构。但是，这是一个需要最少干预的快速解决方案。

删除所有boolean tleft; boolean tmid; ...变量

在main（）方法定义

之外添加此枚举

enum ESide {
  tleft, tmid, tright,
  mleft, mmid, mright,
  bleft, bmid, bright,

};

在适当的位置添加此定义

// checker for if the button already has a character
final Map<ESide, Boolean> board = new HashMap<>();
for (ESide side : ESide.values()) {
    board.put(side, false);
}

使用以下内容替换侦听器，并根据需要调整tleft。但是，请认真考虑制作一个返回鼠标适配器的方法。

    public void mouseClicked(java.awt.event.MouseEvent evt)
    {
        if (board.get(ESide.tleft).booleanValue() == false) {
            topLeft.setText("X");
            board.put(ESide.tleft, true);
        }
    }

您收到的错误将被删除。

最终的局部变量错误

1 个答案: