如何用键盘按钮打印多个数字到标签

Question

您好，这是非常长的对不起我的代码工作，但我怎么打印多个数字到我的标签，只需按下按钮。我的代码不完整，但我只是想在正确的方向推动。感谢您提供任何帮助。

import java.awt.*; 
import javax.swing.*; 
import javax.swing.border.*; 
import java.awt.event.*; 

public class NumericKeyPadPanel extends JPanel { 

    private JButton b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, clear; 
    private JLabel label1; 
    private JPanel primary, panel2, panel3, panel4; 

    public NumericKeyPadPanel() { 
     label1 = new JLabel(); 
     primary = new JPanel(); 
     panel2 = new JPanel(); 
     panel3 = new JPanel(); 
     panel4 = new JPanel(); 
//Set up for the center grid 
     panel2.setLayout(new GridLayout(4, 3)); 
     panel2.setBackground(Color.gray); 
     panel2.setBorder(BorderFactory.createLineBorder(Color.black, 4)); 
//set up for the top box 
     panel3.setBackground(Color.white); 
     panel3.setBorder(BorderFactory.createEtchedBorder()); 
     panel3.add(label1); 
//set up for the bottom 
     panel4.setBackground(Color.gray); 
//set up for the buttons for center and bottom 
     ButtonListener listener1 = new ButtonListener(); 
     ButtonListener listener2 = new ButtonListener(); 
     ButtonListener listener3 = new ButtonListener(); 
     ButtonListener listener4 = new ButtonListener(); 
     ButtonListener listener5 = new ButtonListener(); 
     ButtonListener listener6 = new ButtonListener(); 
     ButtonListener listener7 = new ButtonListener(); 
     ButtonListener listener8 = new ButtonListener(); 
     ButtonListener listener9 = new ButtonListener(); 
     ButtonListener listener10 = new ButtonListener(); 
     ButtonListener listener11 = new ButtonListener(); 
     ButtonListener listener12 = new ButtonListener(); 
     ButtonListener listener13 = new ButtonListener(); 

     b1 = new JButton("1"); 
     b1.addActionListener(listener1); 

     b2 = new JButton("2"); 
     b2.addActionListener(listener2); 

     b3 = new JButton("3"); 
     b3.addActionListener(listener3); 

     b4 = new JButton("4"); 
     b4.addActionListener(listener4); 

     b5 = new JButton("5"); 
     b5.addActionListener(listener5); 

     b6 = new JButton("6"); 
     b6.addActionListener(listener6); 

     b7 = new JButton("7"); 
     b7.addActionListener(listener7); 

     b8 = new JButton("8"); 
     b8.addActionListener(listener8); 

     b9 = new JButton("9"); 
     b9.addActionListener(listener9); 

     b10 = new JButton("*"); 
     b10.addActionListener(listener10); 

     b11 = new JButton("0"); 
     b11.addActionListener(listener11); 

     b12 = new JButton("#"); 
     b12.addActionListener(listener12); 

     clear = new JButton("Clear"); 
     clear.addActionListener(listener13); 

     panel2.add(b1); 
     panel2.add(b2); 
     panel2.add(b3); 
     panel2.add(b4); 
     panel2.add(b5); 
     panel2.add(b6); 
     panel2.add(b7); 
     panel2.add(b8); 
     panel2.add(b9); 
     panel2.add(b10); 
     panel2.add(b11); 
     panel2.add(b12); 
     panel4.add(clear); 
//set up for main panel 
     primary.setLayout(new BorderLayout()); 
     primary.setBackground(Color.gray); 

     primary.add(panel2, BorderLayout.CENTER); 
     primary.add(panel3, BorderLayout.NORTH); 
     primary.add(panel4, BorderLayout.SOUTH); 
     add(primary); 
    } 
    // this is the listener 

    private class ButtonListener implements ActionListener { 

     public void actionPerformed(ActionEvent event) { 
      if (event.getSource() == b1) { 
       label1.setText("1"); 
      } 

     } 
    } 
} 

Answer 1

将要打印的文本存储在单独的实例变量（字符串）中的标签上。每次按下某个按钮时，都会将该号码附加到该文本并将其设置在标签上。

Answer 2

只需追加结果到什么标签已经包含

label.setText(label.getText() + "1");