/*
Core SWING Advanced Programming
By Kim Topley
ISBN: 0 13 083292 8
Publisher: Prentice Hall
*/
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.StyledDocument;
public class AppendingTextPane extends JTextPane {
public AppendingTextPane() {
super();
}
public AppendingTextPane(StyledDocument doc) {
super(doc);
}
// Appends text to the document and ensure that it is visible
public void appendText(String text) {
try {
Document doc = getDocument();
// Move the insertion point to the end
setCaretPosition(doc.getLength());
// Insert the text
replaceSelection(text);
// Convert the new end location
// to view co-ordinates
Rectangle r = modelToView(doc.getLength());
// Finally, scroll so that the new text is visible
if (r != null) {
scrollRectToVisible(r);
}
} catch (BadLocationException e) {
System.out.println("Failed to append text: " + e);
}
}
// Testing method
public static void main(String[] args) {
try {
UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
} catch (Exception evt) {}
JFrame f = new JFrame("Text Pane with Scrolling Append");
final AppendingTextPane atp = new AppendingTextPane();
f.getContentPane().add(new JScrollPane(atp));
f.setSize(200, 200);
f.setVisible(true);
// Add some text every second
Timer t = new Timer(1000, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
String timeString = fmt.format(new Date());
atp.appendText(timeString + "\n");
}
SimpleDateFormat fmt = new SimpleDateFormat("HH:mm:ss");
});
t.start();
}
}