title: Add an actionListener to a JButton from another class
body: <p>so I have two classes testPanel and testFrame. All the buttons are in the testPanel class. I want to add ActionListeners to the Jbuttons in the testFrame class. How do I go about doing this? </p>
  
  <p>testPanel:</p>
  
  <pre><code>public class testPanel extends JPanel{
  
  JLabel codeLbl = new JLabel("Code");
  JLabel titleLbl = new JLabel("Title");
  JLabel priceLbl = new JLabel("Price");
  
  JTextField codeTxt = new JTextField(20);
  JTextField titleTxt = new JTextField(20);
  JTextField priceTxt = new JTextField(20);
  
  JButton addBtn = new JButton("Add");
  JButton updateBtn = new JButton("Update");
  JButton delBtn = new JButton("Delete");
  JButton exitBtn = new JButton("Exit");
  JButton firstBtn = new JButton("First");
  JButton prevBtn = new JButton("Previous");
  JButton nextBtn = new JButton("Next");
  JButton lastBtn = new JButton("Last");
  
  JPanel info = new JPanel();
  JPanel buttons = new JPanel();
  
  public testPanel(){
      info.setLayout(new GridLayout(3,2));
  
      info.add(codeLbl);
      info.add(codeTxt);
      info.add(titleLbl);
      info.add(titleTxt);
      info.add(priceLbl);
      info.add(priceTxt);
  
      buttons.setLayout(new GridLayout(2,4));
  
      buttons.add(addBtn);
      buttons.add(updateBtn);
      buttons.add(delBtn);
      buttons.add(exitBtn);
      buttons.add(firstBtn);
      buttons.add(prevBtn);
      buttons.add(nextBtn);
      buttons.add(lastBtn);
  
      JPanel container = new JPanel();
      container.setLayout(new BorderLayout());
  
      container.add(BorderLayout.CENTER, info);
      container.add(BorderLayout.SOUTH, buttons);
  
      add(container);
  }
  }
  </code></pre>
  
  <p>testFrame:</p>
  
  <pre><code> public class testFrame extends JFrame{
  JPanel p = new testPanel();
  
  public testFrame(){
      super("BLAH");        
  
      this.getContentPane().add(p);setVisible(true);
      pack();
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }
  
  public static void main(String[] args){
      new testFrame();
  }
  </code></pre>
  
  <p>}</p>