exercise24_7.java

java程序设计 机械工业出版社 书籍代码

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

public class Exercise24_7 extends javax.swing.JApplet {
  // Create an array of strings for figure names
  String[] figures = {"Square", "Rectangle", "Circle", "Oval"};

  // Create a list cell renderer
  Exercise24_6CellRenderer myListCellRenderer =
    new Exercise24_6CellRenderer();

  private javax.swing.JComboBox jComboBox1;
  private FigurePanel figurePanel;

  /** Creates new form Exercise24_7 */
  public Exercise24_7() {
    initComponents();

    jComboBox1.addItem("Square");
    jComboBox1.addItem("Rectangle");
    jComboBox1.addItem("Circle");
    jComboBox1.addItem("Oval");
    jComboBox1.setRenderer(myListCellRenderer);

  }

  private void initComponents() {
    jComboBox1 = new javax.swing.JComboBox();
    figurePanel = new FigurePanel();

    jComboBox1.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(java.awt.event.ActionEvent evt) {
        jComboBox1ActionPerformed(evt);
      }
    });

    getContentPane().add(jComboBox1, java.awt.BorderLayout.NORTH);
    getContentPane().add(figurePanel, java.awt.BorderLayout.CENTER);
  }

  private void jComboBox1ActionPerformed(java.awt.event.ActionEvent evt) {
    String figure = (String)(jComboBox1.getSelectedItem());

    if (figure.equals("Square"))
      figurePanel.setFigureType(1);
    else if (figure.equals("Rectangle"))
      figurePanel.setFigureType(2);
    else if (figure.equals("Circle"))
      figurePanel.setFigureType(3);
    else if (figure.equals("Oval"))
      figurePanel.setFigureType(4);

    figurePanel.repaint();
  }

  public static void main(String[] args) {
    Exercise24_7 applet = new Exercise24_7();
    JFrame frame = new JFrame();
    //EXIT_ON_CLOSE == 3
    frame.setDefaultCloseOperation(3);
    frame.setTitle("Exercise24_7");
    frame.getContentPane().add(applet, BorderLayout.CENTER);
    applet.init();
    applet.start();
    frame.setSize(400,320);
    Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
    frame.setLocation((d.width - frame.getSize().width) / 2,
                      (d.height - frame.getSize().height) / 2);
    frame.setVisible(true);
  }
}