package examples;

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

/**
 * CS401 Example 42
 * 
 * Demonstrates the construction of a menu heirarchy. We create an instance of
 * JMenubar, which represents the menu bar of our window. To this, an instance
 * of the JMenu class is added for each menu displayed in the menu bar. Each
 * JMenu also needs to be constructed to contain a set of JMenuItems to display.
 * This program creates a window with JLabel displayed in its center. A set of
 * menus is provided to allow the user to change the color, font, and style of
 * the JLabel as well as exit the program. The menu heiracrchy is created in a
 * bottom-up fashion.
 * 
 * @author PJ Dillon
 */
public class ex42 implements ActionListener, ItemListener
{
	private JMenuItem exit;
	private JRadioButtonMenuItem[] fonts;
	private JRadioButtonMenuItem[] colors;
	private JCheckBoxMenuItem bold;
	private JCheckBoxMenuItem italic;
	private JLabel label;
	
	private static Color[] colorValues = {Color.black, Color.white, Color.red, 
														Color.blue, Color.green};
	public ex42()
	{
		JFrame window = new JFrame("Example 42");
		window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
		/*
		 * A specialized type of JMenuItem is the JRadioButtonMenuItem, a group of 
		 * which act just like JRadioButtons but can be added to a menu. 
		 */
		ButtonGroup colorGroup = new ButtonGroup();
		colors = new JRadioButtonMenuItem[colorValues.length];
		colors[0] = new JRadioButtonMenuItem("Black");
		colors[0].setSelected(true);
		colors[0].addItemListener(this);
		colorGroup.add(colors[0]);
		
		colors[1] = new JRadioButtonMenuItem("White");
		colors[1].addItemListener(this);
		colorGroup.add(colors[1]);
		
		colors[2] = new JRadioButtonMenuItem("Red");
		colors[2].addItemListener(this);
		colorGroup.add(colors[2]);
		
		colors[3] = new JRadioButtonMenuItem("Blue");
		colors[3].addItemListener(this);
		colorGroup.add(colors[3]);
		
		colors[4] = new JRadioButtonMenuItem("Green");
		colors[4].addItemListener(this);
		colorGroup.add(colors[4]);
		
		/*
		 * Create another group for the text font
		 */
		ButtonGroup fontGroup = new ButtonGroup();
		fonts = new JRadioButtonMenuItem[4];
		fonts[0] = new JRadioButtonMenuItem("Sans");
		fonts[0].setSelected(true);
		fonts[0].addItemListener(this);
		fontGroup.add(fonts[0]);
		
		fonts[1] = new JRadioButtonMenuItem("Serif");
		fonts[1].addItemListener(this);
		fontGroup.add(fonts[1]);
		
		fonts[2] = new JRadioButtonMenuItem("Monospaced");
		fonts[2].addItemListener(this);
		fontGroup.add(fonts[2]);
		
		fonts[3] = new JRadioButtonMenuItem("Comic Sans MS");
		fonts[3].addItemListener(this);
		fontGroup.add(fonts[3]);

		/*
		 * As we've seen with previous examples, different styles can be applied 
		 * simultaneously, which makes JCheckBoxMenuItems a good choice to use here.
		 */
		bold = new JCheckBoxMenuItem("Bold");
		bold.addItemListener(this);
		
		italic = new JCheckBoxMenuItem("Italics");
		italic.addItemListener(this);
		
		//create a MenuItem that lets the user exit the program
		exit = new JMenuItem("Exit");
		exit.addActionListener(this);
		
		/*
		 * With all of the menu items created, we start grouping them into JMenus.
		 * A 'File' menu will contain the exit JMenuItem that exits the program.
		 */
		JMenu fileMenu = new JMenu("File");
		fileMenu.addSeparator();
		fileMenu.add(exit);
		
		/*
		 * Create a font menu to display all the Font options
		 */
		JMenu fontMenu = new JMenu("Font");
		for(AbstractButton a : fonts)
			fontMenu.add(a);
		fontMenu.addSeparator();
		fontMenu.add(bold);
		fontMenu.add(italic);
		
		/*
		 * Create a color menu to display all the Color options
		 */
		JMenu colorMenu = new JMenu("Color");
		for(AbstractButton b : colors)
			colorMenu.add(b);
		
		/*
		 * The Font and Color menus are contained as submenus in a Format menu
		 * created here. 
		 */
		JMenu formatMenu = new JMenu("Format");
		formatMenu.add(colorMenu);
		formatMenu.add(fontMenu);
		
		/*
		 * The two upper level menus are then added to a menu bar
		 */
		JMenuBar menubar = new JMenuBar();
		menubar.add(fileMenu);
		menubar.add(formatMenu);
		
		//add the menu bar to the window.
		window.setJMenuBar(menubar);
		
		label = new JLabel("Text To Change", JLabel.CENTER);
		label.setFont(new Font("Sans", Font.PLAIN, 50));
		window.getContentPane().add(label, BorderLayout.CENTER);
		
		window.setSize(500, 200);
		window.setVisible(true);
	}
	
	public void actionPerformed(ActionEvent e)
	{
		System.exit(0);
	}
	
	public void itemStateChanged(ItemEvent e)
	{
		String fontName = null;
		
		/*
		 * With each event that occurs, we don't bother checking the source of the
		 * event. Instead, we simply find the selected font and color from their 
		 * respective groups, compute the style of the text, and set the new Font
		 * object for the JLabel.
		 */
		for(int i = 0; i < colors.length; i++)
			if(colors[i].isSelected())
				label.setForeground(colorValues[i]);
		
		for(AbstractButton a : fonts)
			if(a.isSelected())
				fontName = a.getText();
		
		int style = Font.PLAIN;
		
		if(bold.isSelected())
			style += Font.BOLD;
		if(italic.isSelected())
			style += Font.ITALIC;
		
		
		label.setFont(new Font(fontName, style, 50));	
	}
	
	public static void main(String[] args)
	{
		new ex42();
	}
}