java让JButton按钮变成不可见

因为 i 和 j 是局部变量，在内部类中不允许访问局部变量，如果要访问必须添加 final。所以有个折中的办法，再声明两个中间变量，并定义为 final 类型的，你在内部类中访问这两个中间变量就行了。代码样例：

   for(int i = 0; i < B.length; i++){            
        for(int j = 0; j < B[i].length; j++){                
        B[i][j] = new JButton();                
        B[i][j].setBounds(200 * i , 200 * j + 60 , 200 , 200);                
        B[i][j].setFont(new Font("", Font.BOLD, 150));                
                 
        final a = i; // 中间变量
        final b = j; // 中间变量
        B[a][b].addActionListener(new ActionListener(){                  
            @Override                  
            public void actionPerformed(ActionEvent changeButton){                    
                B[a][b].setText("O");                    
                gameState[a][b] = 'O';                  
            }                
        });            
        }

import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.*;

public class RemoveButton extends JFrame{

public RemoveButton(){

setTitle("点击按钮使它不可见");
setVisible(true);
setSize(222,99);
setLayout(new GridLayout());
JLabel lab = new JLabel("点击下面");
setDefaultCloseOperation(EXIT_ON_CLOSE);
final JButton but = new JButton("按钮");
add(lab);
add(but);
but.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e){

remove(but);
setSize(222,100);

}
});

}

public static void main(String[] args) {
// TODO Auto-generated method stub
new RemoveButton();

}

}

btn.setVisible(false);