java - 在 Java 中找不到符号。 [编译错误]

Question

SlotMachine.java:76: cannot find symbol
symbol  : variable slot
location: class MyFrame.pullHandler

代码

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Random;

class SlotMachine
{
    public static void main(String [] args)
    { 
       MyFrame f = new MyFrame();
    }
}

class MyFrame extends JFrame
{
    JTextField r1 = new JTextField("---",10);
    JTextField r2 = new JTextField("---",10);
    JTextField r3 = new JTextField("---",10);



    JButton pull = new JButton("Pull");
    JLabel result = new JLabel("Not Played Yet");

public MyFrame()
{   

  JTextField [] slot = new JTextField[3];
  slot[0] = new JTextField("---",10);
  slot[1] = new JTextField("---",10);
  slot[2] = new JTextField("---",10);

    JPanel panel = new JPanel();
    setVisible(true);
    setSize(400, 400);  //replace with pack();?
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setTitle("Slot Machine - By: ");

    add(panel);
    panel.add(slot[0]);
    panel.add(slot[1]);
    panel.add(slot[2]);
    panel.add(pull);
    panel.add(result);

    pull.addActionListener(new pullHandler());

}

class pullHandler implements ActionListener
{
    public void actionPerformed(ActionEvent pull)
    {
        int ban = 0;
        int cher = 0; 
        int mel = 0;
        int plays = 0;

        for(int count=0; count< 3; count++) //repeats three times, giving three random values
        {
            Random rand = new Random(); 
            int numRoll = rand.nextInt(3);  //0,1,2 values



        if  (numRoll==0)
            {
                //Bannana
                slot[0].setBackground(Color.yellow);    //I want to replace the 1 with the counts, so if it is the second loop, it would set it for the second box.
                ban++;
                /*slot[count]*/r1.setText("Banana");        
            }

            if (numRoll==1)
            {   
                //cherry
                r2.setBackground(Color.red);
                cher++;
                r2.setText("Cherry");
            }

            if (numRoll==2)
            {
                //Melon
                r3.setBackground(Color.green);
                mel++;
                r3.setText("Melon");  
            }
        }

        plays++;
        result.setText("Played " + plays);  //why don't I keep getting new values when I click "Pull"?

    }
}



}

我试图在我的 pullhandler 类中使用 slot[] 数组而不是 r1/r2/r3 。我尝试阅读旧帖子，但找不到任何与我的问题非常相似的内容。

Answer 1

在构造函数的范围之外，变量slot没有任何意义。如果您希望通过其他方法访问它，请将 slot 移动到字段级别，并使用 JTextField 变量。