comboboxes.java

来自「java编程思想第3版原代码分享是java编程思想一本好书,大家多多学习」· Java 代码 · 共 45 行

//: c14:ComboBoxes.java
// Using drop-down lists.
// <applet code=ComboBoxes width=200 height=125></applet>
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import com.bruceeckel.swing.*;

public class ComboBoxes extends JApplet {
  private String[] description = {
    "Ebullient", "Obtuse", "Recalcitrant", "Brilliant",
    "Somnescent", "Timorous", "Florid", "Putrescent"
  };
  private JTextField t = new JTextField(15);
  private JComboBox c = new JComboBox();
  private JButton b = new JButton("Add items");
  private int count = 0;
  public void init() {
    for(int i = 0; i < 4; i++)
      c.addItem(description[count++]);
    t.setEditable(false);
    b.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        if(count < description.length)
          c.addItem(description[count++]);
      }
    });
    c.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        t.setText("index: "+ c.getSelectedIndex() + "   " +
         ((JComboBox)e.getSource()).getSelectedItem());
      }
    });
    Container cp = getContentPane();
    cp.setLayout(new FlowLayout());
    cp.add(t);
    cp.add(c);
    cp.add(b);
  }
  public static void main(String[] args) {
    Console.run(new ComboBoxes(), 200, 125);
  }
} ///:~