showcolors.java

经典的<<C how to program>一书第三版的例程。非常适合于C的初学者。

// Fig. 28.5: ShowColors.java
// Demonstrating Colors
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

public class ShowColors extends JFrame {
   public ShowColors()
   {
      super( "Using colors" );

      setSize( 400, 130 );
      show();
   }

   public void paint( Graphics g )
   {
      // set new drawing color using integers
      g.setColor( new Color( 255, 0, 0 ) );
      g.fillRect( 25, 25, 100, 20 );
      g.drawString( "Current RGB: " + g.getColor(), 130, 40 );

      // set new drawing color using floats
      g.setColor( new Color( 0.0f, 1.0f, 0.0f ) );
      g.fillRect( 25, 50, 100, 20 );
      g.drawString( "Current RGB: " + g.getColor(), 130, 65 );

      // set new drawing color using static Color objects
      g.setColor( Color.blue );
      g.fillRect( 25, 75, 100, 20 );
      g.drawString( "Current RGB: " + g.getColor(), 130, 90 );
   
      // display individual RGB values
      Color c = Color.magenta;
      g.setColor( c );
      g.fillRect( 25, 100, 100, 20 );
      g.drawString( "RGB values: " + c.getRed() + ", " +
         c.getGreen() + ", " + c.getBlue(), 130, 115 );
   }

   public static void main( String args[] )
   {
      ShowColors app = new ShowColors();

      app.addWindowListener(
         new WindowAdapter() {
            public void windowClosing( WindowEvent e )
            {
               System.exit( 0 );
            }
         }
      );
   }
}

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 * (C) Copyright 2000 by Deitel & Associates, Inc. and Prentice Hall.     *
 * All Rights Reserved.                                                   *
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