使用ActionListener查找事件时遇到问题

Question

I'm just beginning to work with JSwing and trying to learn how to deal with buttons and such, so all critiques will be appreciated and I'll apologize in advance for any basic errors. I'm only trying to create a basic JFrame with two buttons with different outcomes. For some reason the method actionPerformed can not find the button "pressme" even though I use the Action Listener. Can anyone help me find the solution to this? Thank you in advance! -Nick

    import java.util.Scanner;
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    class JPanel  extends JFrame implements ActionListener
    { 
      public JPanel createContentPane(){
        JPanel pane = new JPanel();
        Container con = this.getContentPane();
        JPanel titlePanel = new JPanel();
            titlePanel.setLayout(null);
            titlePanel.setLocation(10, 0);
            titlePanel.setSize(250, 30);
            pane.add(titlePanel);
        JLabel answer = new JLabel("");
            pane.add(answer);
        JLabel label1 = new JLabel("Is Ms. Stilman a savage?",            JLabel.CENTER);
            label1.setSize(150, 15);
            label1.setLocation(250, 10);
            titlePanel.add(label1);
        JButton pressme = new JButton("Nah, what are you talking         about?");
            pane.add(pressme);
            pressme.setMnemonic('P');
            pressme.addActionListener(this);
            pressme.setLocation(250, 10);
            pressme.requestFocus();
        JButton secondpress = new JButton("Yea she's a hardcore savage.");
            pane.add(secondpress);
            secondpress.addActionListener(this);
            secondpress.setLocation(250, 10);
            secondpress.requestFocus();
              }
              public void actionPerformed(ActionEvent event)  {
          Object source = event.getSource();
          if (source == pressme) {
              answer.setText("Button pressed!");
              JOptionPane.showMessageDialog(null, "You're wrong and probably a scrub.", "Message Dialog",
                      JOptionPane.PLAIN_MESSAGE); setVisible(true);
          }
          else if (source == secondpress) {
              answer.setText("Button pressed!");
              JOptionPane.showMessageDialog(null, "Oh ya for sure.",         "Message Dialog",
              JOptionPane.PLAIN_MESSAGE); setVisible(true);
          }
      }
      public static void createAndShowGui(){
       JFrame Frame1 = new JFrame("Button Press Test"); 
            setContentPane(demo.createContentPane());
            setSize(500, 300);
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
            setVisible(true);
      }
    }

Answer 1

your buttons are local variables which are declared and instantiated within a method change them to instance variables ex:

private final JButton pressme;
private final JButton secondpress;

createContentPane(){
pressme = new JButton("Nah, what are you talking         about?");
secondpress =new JButton("Yea she's a hardcore savage.");
}

Answer 2

First, change your class name. It can't be existing class/container's name(JPanel). Second, use class variables instead of local variables for buttons and other UI elements.

== will check if the variable point to the same memory. The object will be destroyed after the method completes it's execution.

If you still are not able execute the listener, for checking which button is pressed, instead of using == operation try using the following type of code:

    button.setActionCommand("-");
    button.addActionListener(this);
    public void actionPerformed(ActionEvent me){

      JButton button =(JButton)me.getSource();
      if(button.getActionCommand().equals("-"))
        //corresponding action to be taken
      }
    }

It has solved the same problem to me a long back ago.