import javax.swing.JOptionPane;
import javax.swing.JDialog;
import javax.swing.JTextField;
import java.beans.*; //property change stuff
import java.awt.*;
import java.awt.event.*;

/* 1.4 example used by DialogDemo.java. */
class CustomDialog extends JDialog
    implements ActionListener,
	       PropertyChangeListener {
  private String typedText = null;
  private JTextField textField;
  private DialogDemo dd;

  private String magicWord;
  private JOptionPane optionPane;

  private String btnString1 = "Enter";
  private String btnString2 = "Cancel";

  /**
   * Returns null if the typed string was invalid;
   * otherwise, returns the string as the user entered it.
   */
  public String getValidatedText() {
    return typedText;
  }

  /** Creates the reusable dialog. */
  public CustomDialog(Frame aFrame, String aWord, DialogDemo parent) {
    super(aFrame, true);
    dd = parent;

    magicWord = aWord.toUpperCase();
    setTitle("Quiz");

    textField = new JTextField(10);

    //Create an array of the text and components to be displayed.
    String msgString1 = "What was Dr. SEUSS's real last name?";
        String msgString2 = "(The answer is \"" + magicWord
	    + "\".)";
        Object[] array = {msgString1, msgString2, textField};

        //Create an array specifying the number of dialog buttons
        //and their text.
        Object[] options = {btnString1, btnString2};

        //Create the JOptionPane.
        optionPane = new JOptionPane(array,
				     JOptionPane.QUESTION_MESSAGE,
				     JOptionPane.YES_NO_OPTION,
				     null,
				     options,
				     options[0]);

        //Make this dialog display it.
        setContentPane(optionPane);

        //Handle window closing correctly.
        setDefaultCloseOperation(DO_NOTHING_ON_CLOSE);
        addWindowListener(new WindowAdapter() {
	      public void windowClosing(WindowEvent we) {
                /*
                 * Instead of directly closing the window,
                 * we're going to change the JOptionPane's
                 * value property.
                 */
		optionPane.setValue(new Integer(
						JOptionPane.CLOSED_OPTION));
	      }
	    });

        //Ensure the text field always gets the first focus.
        addComponentListener(new ComponentAdapter() {
	      public void componentShown(ComponentEvent ce) {
                textField.requestFocusInWindow();
	      }
	    });

        //Register an event handler that puts the text into the option pane.
        textField.addActionListener(this);

        //Register an event handler that reacts to option pane state changes.
        optionPane.addPropertyChangeListener(this);
  }

  /** This method handles events for the text field. */
  public void actionPerformed(ActionEvent e) {
    optionPane.setValue(btnString1);
  }

  /** This method reacts to state changes in the option pane. */
  public void propertyChange(PropertyChangeEvent e) {
    String prop = e.getPropertyName();

    if (isVisible()
	&& (e.getSource() == optionPane)
	&& (JOptionPane.VALUE_PROPERTY.equals(prop) ||
	    JOptionPane.INPUT_VALUE_PROPERTY.equals(prop))) {
      Object value = optionPane.getValue();

      if (value == JOptionPane.UNINITIALIZED_VALUE) {
	//ignore reset
	return;
      }

      //Reset the JOptionPane's value.
      //If you don't do this, then if the user
      //presses the same button next time, no
      //property change event will be fired.
      optionPane.setValue(
			  JOptionPane.UNINITIALIZED_VALUE);

      if (btnString1.equals(value)) {
	typedText = textField.getText();
	String ucText = typedText.toUpperCase();
	if (magicWord.equals(ucText)) {
	  //we're done; clear and dismiss the dialog
	  clearAndHide();
	} else {
	  //text was invalid
	  textField.selectAll();
	  JOptionPane.showMessageDialog(
					CustomDialog.this,
                                    "Sorry, \"" + typedText + "\" "
                                    + "isn't a valid response.\n"
                                    + "Please enter "
					+ magicWord + ".",
					"Try again",
					JOptionPane.ERROR_MESSAGE);
	  typedText = null;
	  textField.requestFocusInWindow();
	}
      } else { //user closed dialog or clicked cancel
	dd.setLabel("It's OK.  "
                         + "We won't force you to type "
		    + magicWord + ".");
	typedText = null;
	clearAndHide();
      }
    }
  }

  /** This method clears the dialog and hides it. */
  public void clearAndHide() {
    textField.setText(null);
    setVisible(false);
  }
}