ShowColors2.java
// Fig. 12.8: ShowColors2.java // Choosing colors with JColorChooser. import javax.swing.JFrame; import java.awt.BorderLayout; import java.awt.Color; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JColorChooser; import javax.swing.JPanel; public class ShowColors2 { // execute application public static void main( String[] args ) { ShowColors2JFrame application = new ShowColors2JFrame(); application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ); } // end main } // end class ShowColors2 class ShowColors2JFrame extends JFrame { private JButton changeColorJButton; private Color color = Color.LIGHT_GRAY; private JPanel colorJPanel; // set up GUI public ShowColors2JFrame() { super( "Using JColorChooser" ); // create JPanel for display color colorJPanel = new JPanel(); colorJPanel.setBackground( color ); // set up changeColorJButton and register its event handler changeColorJButton = new JButton( "Change Color" ); changeColorJButton.addActionListener( new ActionListener() // anonymous inner class { // display JColorChooser when user clicks button public void actionPerformed( ActionEvent event ) { color = JColorChooser.showDialog( ShowColors2JFrame.this, "Choose a color", color ); // set default color, if no color is returned if ( color == null ) color = Color.LIGHT_GRAY; // change content pane's background color colorJPanel.setBackground( color ); } // end method actionPerformed } // end anonymous inner class ); // end call to addActionListener add( colorJPanel, BorderLayout.CENTER ); // add colorJPanel add( changeColorJButton, BorderLayout.SOUTH ); // add button setSize( 400, 130 ); // set frame size setVisible( true ); // display frame } // end ShowColor2JFrame constructor } // end class ShowColors2JFrame
Maintained by John Loomis, updated Tue May 27 12:32:40 2014