/*
* Copyright (c) 2004 David Flanagan. All rights reserved.
* This code is from the book Java Examples in a Nutshell, 3nd Edition.
* It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied.
* You may study, use, and modify it for any non-commercial purpose,
* including teaching and use in open-source projects.
* You may distribute it non-commercially as long as you retain this notice.
* For a commercial use license, or to purchase the book,
* please visit http://www.davidflanagan.com/javaexamples3.
*/
package je3.beans;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.List;
import java.util.ArrayList;
/**
* This JavaBean displays a multi-line message and up to three buttons. It
* fires an AnswerEvent when the user clicks on one of the buttons
**/
public class YesNoPanel extends JPanel {
// Properties of the bean.
protected String messageText; // The message to display
protected Alignment alignment; // The alignment of the message
protected String yesLabel; // Text for the yes, no, & cancel buttons
protected String noLabel;
protected String cancelLabel;
// Internal components of the panel
protected MultiLineLabel message;
protected JPanel buttonbox;
protected JButton yes, no, cancel;
/** The no-argument bean constructor, with default property values */
public YesNoPanel() { this("Your\nMessage\nHere"); }
public YesNoPanel(String messageText) {
this(messageText, Alignment.LEFT, "Yes", "No", "Cancel");
}
/** A constructor for programmers using this class "by hand" */
public YesNoPanel(String messageText, Alignment alignment,
String yesLabel, String noLabel, String cancelLabel)
{
// Create the components for this panel
setLayout(new BorderLayout(15, 15));
// Put the message label in the middle of the window.
message = new MultiLineLabel(messageText, 20, 20, alignment);
message.setOpaque(false); // allow background color to show through
add(message, BorderLayout.CENTER);
// Create a panel for the Panel buttons and put it at the bottom
// of the Panel. Specify a FlowLayout layout manager for it.
buttonbox = new JPanel();
buttonbox.setLayout(new FlowLayout(FlowLayout.CENTER, 25, 15));
buttonbox.setOpaque(false); // allow background color to show through
add(buttonbox, BorderLayout.SOUTH);
// Create each specified button, specifying the action listener
// and action command for each, and adding them to the buttonbox
yes = new JButton(); // Create buttons
no = new JButton();
cancel = new JButton();
// Add the buttons to the button box
buttonbox.add(yes);
buttonbox.add(no);
buttonbox.add(cancel);
// Register listeners for each button
yes.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
fireEvent(new AnswerEvent(YesNoPanel.this,
AnswerEvent.YES));
}
});
no.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
fireEvent(new AnswerEvent(YesNoPanel.this,
AnswerEvent.NO));
}
});
cancel.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
fireEvent(new AnswerEvent(YesNoPanel.this,
AnswerEvent.CANCEL));
}
});
// Now call property setter methods to set the message and button
// components to contain the right text
setMessageText(messageText);
setAlignment(alignment);
setYesLabel(yesLabel);
setNoLabel(noLabel);
setCancelLabel(cancelLabel);
}
// Methods to query all of the bean properties.
public String getMessageText() { return messageText; }
public Alignment getAlignment() { return alignment; }
public String getYesLabel() { return yesLabel; }
public String getNoLabel() { return noLabel; }
public String getCancelLabel() { return cancelLabel; }
public Font getMessageFont() { return message.getFont(); }
public Color getMessageColor() { return message.getForeground(); }
public Font getButtonFont() { return yes.getFont(); }
// Methods to set all of the bean properties.
public void setMessageText(String messageText) {
this.messageText = messageText;
message.setLabel(messageText);
}
public void setAlignment(Alignment alignment) {
this.alignment = alignment;
message.setAlignment(alignment);
}
public void setYesLabel(String l) {
yesLabel = l;
yes.setText(l);
yes.setVisible((l != null) && (l.length() > 0));
}
public void setNoLabel(String l) {
noLabel = l;
no.setText(l);
no.setVisible((l != null) && (l.length() > 0));
}
public void setCancelLabel(String l) {
cancelLabel = l;
cancel.setText(l);
cancel.setVisible((l != null) && (l.length() > 0));
}
public void setMessageFont(Font f) {
message.setFont(f);
}
public void setMessageColor(Color c) {
message.setForeground(c);
}
public void setButtonFont(Font f) {
yes.setFont(f);
no.setFont(f);
cancel.setFont(f);
}
/** This field holds a list of registered ActionListeners. */
protected List listeners = new ArrayList();
/** Register an action listener to be notified when a button is pressed */
public void addAnswerListener(AnswerListener l) { listeners.add(l); }
/** Remove an Answer listener from our list of interested listeners */
public void removeAnswerListener(AnswerListener l) { listeners.remove(l); }
/** Send an event to all registered listeners */
public void fireEvent(AnswerEvent e) {
// Make a copy of the list and fire the events using that copy.
// This means that listeners can be added or removed from the original
// list in response to this event.
Object[] copy = listeners.toArray();
for(int i = 0; i < copy.length; i++) {
AnswerListener listener = (AnswerListener) copy[i];
switch(e.getID()) {
case AnswerEvent.YES: listener.yes(e); break;
case AnswerEvent.NO: listener.no(e); break;
case AnswerEvent.CANCEL: listener.cancel(e); break;
}
}
}
/** A main method that demonstrates the class */
public static void main(String[] args) {
// Create an instance of YesNoPanel, with title and message specified:
YesNoPanel p = new YesNoPanel("Do you really want to quit?");
// Register an action listener for the Panel. This one just prints
// the results out to the console.
p.addAnswerListener(new AnswerListener() {
public void yes(AnswerEvent e) { System.exit(0); }
public void no(AnswerEvent e) { System.out.println("No"); }
public void cancel(AnswerEvent e) {
System.out.println("Cancel");
}
});
JFrame f = new JFrame();
f.getContentPane().add(p);
f.pack();
f.setVisible(true);
}
}
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