import javax.swing.*;
import java.awt.*;
import javax.swing.event.*;
import java.awt.event.*;
public class HistoryEditor extends JFrame{


public static Color randomColor(){
    return new Color((float)Math.random(), (float)Math.random(), (float)Math.random());
}

public HistoryEditor(){

    setLayout(new BorderLayout());

    final JPanel mainPanel = new JPanel();
    mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.Y_AXIS));
    JPanel controlPanel = new JPanel(new FlowLayout());
    final JTextField tf = new JTextField(20);
    JButton addVertical = new JButton("Add Vertical");
    JButton addHorizontal = new JButton("Add Horizontal");
    JButton removeVertical = new JButton("Remove Vertical");

    addVertical.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){
            JPanel newPanel = new JPanel();
            newPanel.setPreferredSize( new Dimension(getWidth(), 50) );
            newPanel.setMaximumSize( newPanel.getPreferredSize() );
            newPanel.setMinimumSize( newPanel.getPreferredSize() );
            newPanel.setBackground( HistoryEditor.randomColor() );
            newPanel.setLayout( new BoxLayout( newPanel, BoxLayout.X_AXIS ) );

            JPanel eventPanel = new JPanel();
            eventPanel.setBackground( HistoryEditor.randomColor() );
            eventPanel.setMaximumSize( new Dimension(50, newPanel.getHeight() ) );
            eventPanel.setMinimumSize( new Dimension(50, newPanel.getHeight() ) );
            eventPanel.setPreferredSize( new Dimension(50, newPanel.getHeight() ) );
            eventPanel.add( new JLabel( tf.getText() ) );
            eventPanel.revalidate();
            newPanel.add(eventPanel);
            newPanel.revalidate();
            mainPanel.add( newPanel );
            mainPanel.revalidate();
            mainPanel.repaint();
            eventPanel.repaint();


        }
    });

    addHorizontal.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){
            try{
                int index = Integer.parseInt(tf.getText());
                JPanel selectedPanel = (JPanel)mainPanel.getComponent( index );

                JPanel eventPanel = new JPanel();
                eventPanel.setBackground( HistoryEditor.randomColor() );
                eventPanel.setMaximumSize(new Dimension(50, selectedPanel.getHeight()));
                eventPanel.setMinimumSize(new Dimension(50, selectedPanel.getHeight()));
                eventPanel.add( new JLabel( tf.getText() ) );
                selectedPanel.add(eventPanel);
                selectedPanel.revalidate();
                selectedPanel.repaint();

            }catch(Exception ex){}
        }
    });


    removeVertical.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){
            try{
                int index = Integer.parseInt(tf.getText());
                mainPanel.remove(index);
                mainPanel.revalidate();
                mainPanel.repaint();

            }catch(Exception ex){}
        }
    });


    controlPanel.add(tf);
    controlPanel.add(addVertical);
    controlPanel.add(addHorizontal);
    controlPanel.add(removeVertical);
    add(mainPanel, BorderLayout.CENTER);
    add(controlPanel, BorderLayout.SOUTH);
    setSize(1000, 1000);
    setVisible(true);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

}

public static void main(String[]args){
    HistoryEditor he = new HistoryEditor();
}

}