textarea.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:TextArea.java
// Using the JTextArea control.
// 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 java.util.*;
import com.bruceeckel.swing.*;
import com.bruceeckel.util.*;

public class TextArea extends JFrame {
  private JButton
    b = new JButton("Add Data"),
    c = new JButton("Clear Data");
  private JTextArea t = new JTextArea(20, 40);
  private Map m = new HashMap();
  public TextArea() {
    // Use up all the data:
    Collections2.fill(m, Collections2.geography,
      CountryCapitals.pairs.length);
    b.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        Iterator it = m.entrySet().iterator();
        while(it.hasNext()) {
          Map.Entry me = (Map.Entry)(it.next());
          t.append(me.getKey() + ": "+ me.getValue()+"\n");
        }
      }
    });
    c.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        t.setText("");
      }
    });
    Container cp = getContentPane();
    cp.setLayout(new FlowLayout());
    cp.add(new JScrollPane(t));
    cp.add(b);
    cp.add(c);
  }
  public static void main(String[] args) {
    Console.run(new TextArea(), 475, 425);
  }
} ///:~