title: java delete a component
body: <p>Current I can add a bunch of customed component objects to the JPanel by pressing "add" JButton. I also got a "delete" JButton which I wish to do the opposite of "add".</p>
  
  <p>My intention is that I can select a component with a mouse and click the delete button and pressto!, the component is gone.</p>
  
  <p>I hook a MouseListener to the panel, and use MouseEvent, e.getComponent() to get w/e current component the mouse clicks on. So if it returns a custom component then a variable  "private myComponent current" (already set to null) will point to that component. Then I can just click on "delete" button to remove it. An actionListener already added in "delete" button and in the body it calls this.remove(current) (if current is not null).</p>
  
  <p>However, this doesn't work as I can't remove a component! Any pointer?</p>
  
  <p>If there is an elegant way to managing add/remove components please suggest! </p>
  
  <pre><code>public class MainDisplayPanel extends JPanel implements ActionListener, MouseListener{
  
  private JButton newClassButton;
  private JButton deleteButton;
  private Resizable current;
  private Resizable resizer;
  public MainDisplayPanel(LayoutManager layout) {
      super(layout);
  
      newClassButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
              addResizer();
       }          
      });
  
      deleteButton = new JButton("Delete");
      deleteButton.addActionListener(this);
      this.addMouseListener(this);
      this.add(newClassButton);
      this.add(deleteButton);
  
  }
  public void addResizer() {
      //JPanel panel = new JPanel();
      //panel.setBackground(Color.white);
       resizer = new Resizable( new ClassBox());
      this.add(resizer);
      this.revalidate();
      this.repaint();
  }
  
  public void actionPerformed(ActionEvent e) {
            if(current!=null)
            {
                this.remove(current);
                this.revalidate();
                this.repaint();
  
            }
  }
  
  public void mouseClicked(MouseEvent e) {
      System.out.println(e);
              Component component = e.getComponent();
  
              if(component instanceof Resizable)
                  current= (Resizable) e.getComponent();
  
  }
  
  
      public static void main(String[] args) {
      JFrame jframe = new JFrame();
      jframe.add(new MainDisplayPanel(null));
      jframe.setSize(new Dimension(600,400));
      jframe.setVisible(true);
      jframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }
  </code></pre>
  
  <p>}
  Doh!</p>
  
  <p>Now, in the addResizer() method. Every time I press the add button to add a new Resizable object, what'd happen to the previously added objects? I'm certain that they become null because resizer variable no longer referring to it them??? Even if this is the case, they are still displayed on the panel...And if I pressed delete only the newly added Resizable object gets removed. So am I on the right track here?</p>
  
  <p>Edit: to sum up my problem, I hooked the MouseListener to wrong object. It should be Resizable object instead of the panel. Therefore, variable current is always null.</p>