//	3/13/2013 Greenstein: changed from applet to JFrame


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


public class KeyboardAndFocusDemo 
                  implements KeyListener, FocusListener, MouseListener 
{
	static final int SQUARE_SIZE = 40;  // Length of a side of the square.
   
	Color squareColor;  // The color of the square.
   
	int squareTop, squareLeft;  // Coordinates of top-left corner of square.
   
	boolean focussed = false;   // True when this applet has input focus.
   
	JFrame frame;
	DisplayPanel canvas;  // The drawing surface on which the applet draws.
	final int XSIZE = 500, YSIZE = 500;
   
	public static void main(String[] args) 
	{
		KeyboardAndFocusDemo kafd = new KeyboardAndFocusDemo();
		kafd.Run();
	}

	public void Run() 
	{
		// Create a frame to hold everything
		frame = new JFrame ("Hear Mouse");
		frame.setSize(XSIZE, YSIZE);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		//frame.setBackground(Color.black);	// only needed if frame is larger than panel
		
		// Define panel to draw on
		canvas = new DisplayPanel();		// create a panel to draw on
      		canvas.setBackground(Color.white);
		canvas.addFocusListener(this);   // Set up the applet to listen for events
		canvas.addKeyListener(this);     //                          from the canvas.
		canvas.addMouseListener(this);	// connects the MouseListerner to the panel window
		
		// Put frame together
		frame.getContentPane().add(canvas);	// puts panel on frame
		frame.setVisible(true);
        
		squareTop = YSIZE / 2 - SQUARE_SIZE / 2;
		squareLeft = XSIZE / 2 - SQUARE_SIZE / 2;
		squareColor = Color.red;
      
	} // end Run();
   
   
	class DisplayPanel extends JPanel 
	{

		public void paintComponent(Graphics g) 
		{
      
			super.paintComponent(g);  // Fills the panel with its
                                   // background color, which is white.

			if (focussed) 
			g.setColor(Color.cyan);
			else
			g.setColor(Color.lightGray);

			int width = getSize().width;  // Width of the applet.			
			int height = getSize().height; // Height of the applet.
			g.drawRect(0,0,width-1,height-1);
			g.drawRect(1,1,width-3,height-3);
			g.drawRect(2,2,width-5,height-5);

			g.setColor(squareColor);
			g.fillRect(squareLeft, squareTop, SQUARE_SIZE, SQUARE_SIZE);

         /* If the applet does not have input focus, print a message. */

         	if (!focussed) 
			{
				g.setColor(Color.magenta);
				g.drawString("Click to activate",7,20);
			}

		}  // end paintComponent()
    
	} // end nested class DisplayPanel 
    
    

   // ------------------- Event handling methods ----------------------
   
	public void focusGained(FocusEvent evt) 
	{
		// The applet now has the input focus.
		focussed = true;
		canvas.repaint();  // redraw with cyan border
	}
   

	public void focusLost(FocusEvent evt) 
	{
		// The applet has now lost the input focus.
		focussed = false;
		canvas.repaint();  // redraw without cyan border
	}
   
   
	public void keyTyped(KeyEvent evt) 
	{
		char ch = evt.getKeyChar();  // The character typed.

		if (ch == 'B' || ch == 'b') 
		{
			squareColor = Color.blue;
			canvas.repaint();
		}
		else if (ch == 'G' || ch == 'g') 
		{
			squareColor = Color.green;
			canvas.repaint();
		}
		else if (ch == 'R' || ch == 'r') 
		{

			squareColor = Color.red;
			canvas.repaint();
		}
		else if (ch == 'K' || ch == 'k') 
		{
			squareColor = Color.black;
			canvas.repaint();
		}

	}  // end keyTyped()
   
   
	public void keyPressed(KeyEvent evt) 
	{ 
		int key = evt.getKeyCode();  // keyboard code for the key that was pressed
      
		if (key == KeyEvent.VK_LEFT) 
		{
			squareLeft -= 8;
			if (squareLeft < 3)
			  squareLeft = 3;
			canvas.repaint();
		}
		else if (key == KeyEvent.VK_RIGHT) 
		{
			squareLeft += 8;
			if (squareLeft > XSIZE - 3 - SQUARE_SIZE)
			  squareLeft = YSIZE - 3 - SQUARE_SIZE;
			canvas.repaint();
		}
		else if (key == KeyEvent.VK_UP) 
		{
			squareTop -= 8;
			if (squareTop < 3)
			  squareTop = 3;
			canvas.repaint();
		}
		else if (key == KeyEvent.VK_DOWN) 
		{
			squareTop += 8;
			if (squareTop > YSIZE - 3 - SQUARE_SIZE)
			  squareTop = YSIZE - 3 - SQUARE_SIZE;
			canvas.repaint();
		}

	}  // end keyPressed()


   public void keyReleased(KeyEvent evt) 
	{ 
		// empty method, required by the KeyListener Interface
	}
   

   public void mousePressed(MouseEvent evt) 
	{
		// Request that the input focus be given to the
		// canvas when the user clicks on the applet.
		canvas.requestFocus();
	}   
   
   
	public void mouseEntered(MouseEvent evt) { }  // Required by the
	public void mouseExited(MouseEvent evt) { }   //    MouseListener
	public void mouseReleased(MouseEvent evt) { } //       interface.
	public void mouseClicked(MouseEvent evt) { }


} // end class KeyboardAndFocusDemo