package examples;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/**
 * CS401 Example 34
 * 
 * Demonstrates some of the capabilities of the FlowLayout Layout Manager Class.
 * The FlowLayout manager arranges components in order they are added to the
 * container from left to right across the space of the container. When there 
 * isn't enough space in the row for the next component, a new line is started. 
 * The excess space in a row can be distributed around the components much like
 * words on a page: the components can be left justified, right justified, or
 * centered.
 * 
 * @author PJ Dillon
 */
public class ex34
{
	private Container c;
	private FlowLayout layout;

	public ex34()
	{
		JFrame window = new JFrame("FlowLayout");
		window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		c = window.getContentPane();
		
		/*
		 * Create the Layout Manager and set it to manage the content pane of our
		 * JFrame
		 */
		layout = new FlowLayout();
		c.setLayout(layout);

		JButton left, right, center;
		left = new JButton("Left");
		right = new JButton("Right");
		center = new JButton("Center");

		/*
		 * Here we're using anonymous inner classes. Recall that ActionListener is
		 * an interface, meaning we can't create instances of it. The code below
		 * automatically creates a new class declared inside the ex34 class that 
		 * implements the ActionListener interface. The new class then contains the
		 * methods and instance variables defined inside the braces. An instance of
		 * this class is created here and given to the addActionListener method.
		 * Note that only one instance of this class is ever created, and we're 
		 * unable to refer to this class elsewhere.
		 */
		left.addActionListener(new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					layout.setAlignment(FlowLayout.LEFT);
					layout.layoutContainer(c);
				}
			});
		
		center.addActionListener(new ActionListener()
				{
					public void actionPerformed(ActionEvent e)
					{
						layout.setAlignment(FlowLayout.CENTER);
						layout.layoutContainer(c);
					}
				});
		
		right.addActionListener(new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					layout.setAlignment(FlowLayout.RIGHT);
					layout.layoutContainer(c);
				}
			});
		
		c.add(left);
		c.add(center);
		c.add(right);
		
		window.setSize(300, 80);
		window.setVisible(true);
	}

	public static void main(String[] args)
	{
		new ex34();
	}

}