Thread: Managing layout in JFrame

I have the following class. When I comment out this.add( rightPanel ); leftPanel appears perfectly. When I comment out this.add( leftPanel );, my rightPanel animates perfectly. When I have both, I only see rightPanel.

How can I manipulate my layout (potentially with a layout manager such as FlowLayout or BoxLayout) to see both objects?

import javax.swing.*;
import java.awt.Dimension;
 
public class MainFrame extends JFrame
{
  JPanel leftPanel;   // Contains some TJextField, JButton, JLabel objects
  JApplet rightPanel; // Shows an animation
 
  public MainFrame(String name)
  {
    super(name);
 
    leftPanel = new LeftPane(); 
    rightPanel = new RightPane();
 
    // This is a failed attempt to avoid losing my leftPanel
    leftPanel.setMinimumSize( new Dimension( 120, 100) );
 
    this.add( leftPanel );
    this.add( rightPanel );
 
    rightPanel.start();
  }
}

JFrame uses BorderLayout by default and adds components to BorderLayout.CENTER if no other location is specified. Adding two items to the default location will show only the last item added. Either use another layout or add the two components to different locations.

Interesting, I thought it used FlowLayout by default. I will lookup BorderLayout and figure out how to manipulate it.

--- Update ---

Great! Fixed it with:

this.add( leftPanel , BorderLayout.LINE_START);
this.add( rightPanel , BorderLayout.CENTER);

Note using LINE_START and LINE_END in combination didn't work, so I'm not sure if there is default sizing for CENTER which forces extra space in there.