fontdialog.java

Java编程例子(全新)演示基础的Java 功能,例如类,对象的使用,过程的调用,.

/**
   @version 1.32 2004-05-06
   @author Cay Horstmann
*/

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

public class FontDialog
{
   public static void main(String[] args)
   {  
      FontDialogFrame frame = new FontDialogFrame();
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.setVisible(true);
   }
}

/**
   A frame that uses a grid bag layout to arrange font
   selection components.
*/
class FontDialogFrame extends JFrame
{  
   public FontDialogFrame()
   {  
      setTitle("FontDialog");
      setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);

      GridBagLayout layout = new GridBagLayout();
      setLayout(layout);

      ActionListener listener = new FontAction();

      // construct components
      
      JLabel faceLabel = new JLabel("Face: ");

      face = new JComboBox(new String[] 
         {  
            "Serif", "SansSerif", "Monospaced", 
            "Dialog", "DialogInput" 
         });
      
      face.addActionListener(listener);

      JLabel sizeLabel = new JLabel("Size: ");

      size = new JComboBox(new String[]
         {
            "8", "10", "12", "15", "18", "24", "36", "48"
         });

      size.addActionListener(listener);

      bold = new JCheckBox("Bold");
      bold.addActionListener(listener);

      italic = new JCheckBox("Italic");
      italic.addActionListener(listener);

      sample = new JTextArea();
      sample.setText("The quick brown fox jumps over the lazy dog");
      sample.setEditable(false);
      sample.setLineWrap(true);
      sample.setBorder(BorderFactory.createEtchedBorder());

      // add components to grid, using GBC convenience class

      add(faceLabel, new GBC(0, 0).setAnchor(GBC.EAST));
      add(face, new GBC(1, 0).setFill(GBC.HORIZONTAL).setWeight(100, 0).setInsets(1));
      add(sizeLabel, new GBC(0, 1).setAnchor(GBC.EAST));
      add(size, new GBC(1, 1).setFill(GBC.HORIZONTAL).setWeight(100, 0).setInsets(1));
      add(bold, new GBC(0, 2, 2, 1).setAnchor(GBC.CENTER).setWeight(100, 100));
      add(italic, new GBC(0, 3, 2, 1).setAnchor(GBC.CENTER).setWeight(100, 100));
      add(sample, new GBC(2, 0, 1, 4).setFill(GBC.BOTH).setWeight(100, 100));
   }

   public static final int DEFAULT_WIDTH = 300;
   public static final int DEFAULT_HEIGHT = 200;  

   private JComboBox face;
   private JComboBox size;
   private JCheckBox bold;
   private JCheckBox italic;
   private JTextArea sample;

   /**
      An action listener that changes the font of the 
      sample text.
   */
   private class FontAction implements ActionListener
   {
      public void actionPerformed(ActionEvent event)
      {  
         String fontFace = (String) face.getSelectedItem();
         int fontStyle = (bold.isSelected() ? Font.BOLD : 0)
            + (italic.isSelected() ? Font.ITALIC : 0);
         int fontSize = Integer.parseInt((String) size.getSelectedItem());
         Font font = new Font(fontFace, fontStyle, fontSize);
         sample.setFont(font);
         sample.repaint();
      }
   }
}