/*
 * 1.1 code.
 */

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;

public class TextEventDemo extends Applet 
                           implements ActionListener {
    TextField textField;
    TextArea textArea;
    TextArea displayArea;

    public void init() {
	Button button = new Button("Clear");
	button.addActionListener(this);

	textField = new TextField(20);
	textField.addActionListener(new MyTextActionListener());
	textField.addTextListener(new MyTextListener("Text Field"));

        textArea = new TextArea(5, 20);
	textArea.addTextListener(new MyTextListener("Text Area"));

	displayArea = new TextArea(5, 20);
	displayArea.setEditable(false);

	GridBagLayout gridbag = new GridBagLayout();
	GridBagConstraints c = new GridBagConstraints();
	setLayout(gridbag);
	c.fill = GridBagConstraints.BOTH;
	c.weightx = 1.0;

	/*
	 * Hack to get around gridbag's refusal to allow
	 * multi-row components in anything but the left column.
	 */
	Panel leftPanel = new Panel();
	leftPanel.setLayout(new BorderLayout());
	leftPanel.add("North", textField);
	leftPanel.add("Center", textArea);

	c.gridheight = 2;
	gridbag.setConstraints(leftPanel, c);
	add(leftPanel);

	c.weighty = 1.0;
	c.gridwidth = GridBagConstraints.REMAINDER;
	c.gridheight = 1;
	gridbag.setConstraints(displayArea, c);
	add(displayArea);

	c.weighty = 0.0;
	gridbag.setConstraints(button, c);
	add(button);

	textField.requestFocus();
    }

    class MyTextListener implements TextListener {
	String preface;
        String newline;

	public MyTextListener(String source) {
	    newline = System.getProperty("line.separator");
	    preface = source
		      + " text value changed."
		      + newline
		      + "   First 10 characters: \"";
	}

        public void textValueChanged(TextEvent e) {
	    TextComponent tc = (TextComponent)e.getSource();
	    String s = tc.getText();
	    try {
		s = s.substring(0, 10);
	    } catch (StringIndexOutOfBoundsException ex) {
	    }

	    displayArea.append(preface + s + "\"" + newline);

            //Scroll down, unless the peer still needs to be created.
	    if (displayArea.isValid()) {
	        displayArea.setCaretPosition(java.lang.Integer.MAX_VALUE);
	    } 
	}
    }

    class MyTextActionListener implements ActionListener {
        /** Handle the text field Return. */
        public void actionPerformed(ActionEvent e) {
	    int selStart = textArea.getSelectionStart();
	    int selEnd = textArea.getSelectionEnd();

            textArea.replaceRange(textField.getText(),
	                          selStart, selEnd);
            textField.selectAll();
        }
    }

    /** Handle button click. */
    public void actionPerformed(ActionEvent e) {
	displayArea.setText("");
	textField.requestFocus();
    }
}