Question

我目前正在尝试创建一个简单的访问面板，允许用户点击数字，它将显示在上面的textfield中，但是当点击该按钮时，textfield正在填充但是以前的号码正在被覆盖！下面显示了我目前的代码。这是btn1＆amp; btn2我正在关注这一点：

package securitySystem;

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

public class accessPanel extends JFrame {

public static void main (String args[]){
    accessPanel gui= new accessPanel ();
    gui.setSize (360, 400);
    gui.setLocationRelativeTo(null);
    gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    gui.setVisible(true);
    gui.setTitle("Access Panel");

    gui.setLayout(new BorderLayout());
    gui.setBackground(Color.BLACK);

}   

JButton btn1= new JButton("1");
JButton btn2= new JButton("2");
JButton btn3= new JButton("3");
JButton btn4= new JButton("4");
JButton btn5= new JButton("5");
JButton btn6= new JButton("6");
JButton btn7= new JButton("7");
JButton btn8= new JButton("8");
JButton btn9= new JButton("9");
JButton btn0= new JButton("0");

JTextField pin = new JTextField();


public accessPanel (){
    setLayout(null);

    pin.setBounds(0,0,340,40);
    add(pin);       
    btn1.setBounds(0,40,100,70);
    add(btn1);
    btn2.setBounds(120,40,100,70);
    add(btn2);
    btn3.setBounds(240,40,100,70);
    add(btn3);
    btn4.setBounds(0,120,100,70);
    add(btn4);
    btn5.setBounds(120,120,100,70);
    add(btn5);
    btn6.setBounds(240,120,100,70);
    add(btn6);
    btn7.setBounds(0,200,100,70);
    add(btn7);
    btn8.setBounds(120,200,100,70);
    add(btn8);
    btn9.setBounds(240,200,100,70);
    add(btn9);
    btn0.setBounds(120,280,100,70);
    add(btn0);
}

public void calcButtons()
{
    btn1.addActionListener(new ActionListener() 
    {
        public void actionPerformed(ActionEvent e) 
        {
            pin.setText(btn1.getText());
        }
    });
    btn2.addActionListener(new ActionListener() 
    {
        public void actionPerformed(ActionEvent e) 
        {
            pin.setText(btn2.getText());
        }
    }); 
}
}

Answer 1

拥有一个全局字符串，您可以在每次单击按钮时添加数字

public class accessPanel extends JFrame {
    String word = "";

    ...
    btn2.addActionListener(new ActionListener() 
    {
        public void actionPerformed(ActionEvent e) 
        {
            word += btn2.getText();
            pin.setText(word);
        }
    });
}

如果您有clear按钮，只需在其actionPerformed中将字符串设置为""

输入的先前数字被覆盖JFRAME

1 个答案: