Develop Reference

netbeans setDefaultCloseOperation

I am trying to set the default close operation in NetBeans 8.0.2 (in Ubuntu 14.04 on an older Asus gaming laptop.) My program is very large but uses no JFrame or java.swing components.
I merely need to save some values when the "x" in the lower right corner is clicked (this is one usual way to stop execution of a java program in NetBeans.)
I found suggestions that involved swing & JFrame, but it wasn't clear just where to insert the code:
DefaultApplicationView view = new DefaultApplicationView(this);
javax.swing.JFrame frame = view.getFrame();
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.addWindowListener(new WindowAdapter(){
public void WindowClosing(WindowEvent e){
System.out.println("CLOSING");
}
}
show(view);
I also found a set of instructions that I think I would prefer to use, but the post is old enough that my NetBeans doesn't have the tabs/menu-items referred to:
Set Window to Design Mode by clicking the 'Design' Tab
In the Navigator: Right click the 'JFrame' -> 'Properties'
In the Properties Tab: Set 'defaultCloseOperation' (top of the list) to 'DO_NOTHING'
Select 'Events' Tab
Scroll down to 'windowClosing'
Click on the "..." button on the right of the event to bring up the custom editor
Click 'Add...' and name the handler (i.e. custom function that you want to have execute on click of the 'X', or window close event).
Click 'Ok'
Netbeans now automatically creates the function and takes to you the function body in the source view
Now simply add what you want to do here: eg. dispose(), or system.exit or pintln(), or whatever your heart desires, as long as its JAVA and makes sense to the app.
Then there are a few other possibly relevant posts, but they all explicitly involve JFrame and/or swing. (Am I ignorant of some fact such as "All NetBeans java applications use JFrame", or some such?)
A pared down example of code for what I'm trying to do would be:
public class MyApp{
public static void main(String[] args){
loadMyVariables();
// do some work that changes variables' values
// during this work user clicks the 'x' box to halt execution
// I need then automatically to save the variables' new values
}
// needs to be called by the OS or GUI when execution is halted by user
public static void saveMyVariables{
// here the usual printStream stuff saves some values to a file
System.exit(0);
}
public static void loadMyVariables{
// here the usual Scanner stuff reads some values from a file
}
}
(I need help setting the tags for this, so I'm doing as instructed and asking the community.)
THANKS

(Java Swing) Stalling actionPerformed Command Until A Dialog Returns

I need to create a JDialog, or a JFrame class (it doesn't particularly matter so long as it's a graphical interface) - that can be used in a static command that is called from the within the actionPerformed(ActionEvent) handler and will stall that process until the user provides their selections from the user interface.
Obviously it is possible to do, because this is exactly what the dialogs JOptionPane creates does. But when I try to stall the thread until the user has completed the selection process, the interface doesn't display properly.
Here is the part of my code that I'm having trouble with:
public static Results queryForResults(String message, int propertyOne,
int propertyTwo){
MyCustomDialog mcd = new MyCustomDialog(message, propertyOne,propertyTwo);
mcd.show();
// complete() is a boolean property of my MyCustomDialog class that turns
// true when the interface has been completed.
while(!mcd.complete()){
synchronized(mcd){
try{
mcd.wait(10000L);
} catch(InterruptedException e) {
e.printStackTrace();
return null;
}
}
}
mcd.dispose();
// My MyCustomDialog class has a getResults() property which returns
// a Results object (i.e. another custom class I've made to contain
// the selections made by the user.)
return mcd.getResults();
}
The dialog outer frame appears, but it's insides don't. They just seem to be a screen capture of whatever was on the screen beneath the dialog when it appeared. I get the impression that this isn't working because I'm not supposed to be stalling the Swing Event thread with the wait command. So how do you do it?

There is no need for a while loop. A modal JDialog will cause execution to stop in your ActionLIstener until the dialog is closed.
Also, don't use the show() method to display a dialog. You should be using the setVisible(true) method.

Call to jFrame from jInternalFrame does not work

I have a main jFrame HomePage.java and many other classes which extend javax.swing.JInternalFrame. One of the classes (JInternalFrame) is Login.java. Now I check whether the password is correct in Login.java and if the password is correct, I load success.java. Now the problem arises when I have to load the success.java page.
I have a function in the HomePage.java whose purpose is to remove all internal frames and load success.java class. The function is as follows :-
public void LogIn(){
jDesktopPane1.removeAll();
System.out.println("Pos 2");
success frame = new success();
frame.setVisible(true);
jDesktopPane1.add(frame);
setContentPane(jDesktopPane1);
try {
frame.setSelected(true);
} catch (java.beans.PropertyVetoException e) {
}
}
I call the function in the Login.java page as follows :-
System.out.println("Pos 1 ");
(new HomePage()).LogIn();
The logic does not work. But, I receive the output as
Pos 1
Pos 2
which shows that the program flow was correct. I do not get any error also. Another weird factor is that when I calthe same LogIn() function from the menu in the jFrame itself, I get the desired output. Please solve my dilemma. Any help will surely be appreciated!

This code:
System.out.println("Pos 1 ");
(new HomePage()).LogIn();
Creates a new HomePage object and calls a method on it. Oh you are certainly calling the correct method, and it's going a HomePage instance, but it's not the correct HomePage instance, not the one that's displayed, because you've created a new one.
Short term solution: get a valid reference to the displayed HomePage instance and call your method on it. You could get it by passing it into the class that needs it as a constructor or method parameter, or you could use SwingUtilities.getWindowAncestor(...).
i.e.,
Window window = SwingUtilities.getWindowAncestor(Login.this);
if (window instanceof HomePage) {
HomePage validHomePageRef = (HomePage) window;
validHomePageRef.logIn();
}
Long term solution: don't create spaghetti code with GUI objects changing behaviors of other GUI objects, but instead refactor your code a la MVC or one of its variants, so the GUI can change the model and the other GUI objects can be notified of these changes via listeners and respond if they want.

How do I change the value of a JOptionPane from a PropertyChangeListener without triggering the listener?

I am trying to make a program to manage a group of sports players. Each player has an enum Sport, and SportManager has convenient factory methods. What I am trying to do is open a dialog that has a JTextField for a name and a combo box to choose a sport. However, I want to stop the user from closing the dialog while the text field is blank, so I wrote a PropertyChangeListener so that when the text field is blank, it would beep to let the user know. However, if the user puts in something in the text after setting off the beep, it doesn't trigger the listener and you can't close the dialog without pressing cancel because the value is already JOptionPane.OK_OPTION, and cancel is the only way to change JOptionPane.VALUE_PROPERTY. So I tried to add
message.setValue(JOptionPane.UNITIALIZED_VALUE);
within the listener. However this just closes the window right away without giving the user a chance to fill in the text field, presumably because it triggers the listener I just registered. How do I make it so that it will beep more than once and give the user a chance to fill in the field?
FYI newPlayer is the component I'm registering the action to.
Code:
newPlayer.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
Object[] msg = new Object [4];
msg[0] = new JLabel("Name:");
final JTextField nameField = new JTextField();
msg[1]=nameField;
msg[2] = new JLabel("Sport: ");
JComboBox<Sport> major = new JComboBox<Sport>(SportManager.getAllSports());
msg[3]=major;
final JOptionPane message = new JOptionPane();
message.setMessage(msg);
message.setMessageType(JOptionPane.PLAIN_MESSAGE);
message.setOptionType(JOptionPane.OK_CANCEL_OPTION);
final JDialog query = new JDialog(gui,"Create a new player",true);
query.setContentPane(message);
query.setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE);
message.addPropertyChangeListener(
new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent e) {
String prop = e.getPropertyName();
if (query.isVisible()&& (e.getSource() == message)&& (prop.equals(JOptionPane.VALUE_PROPERTY))) {
if(nameField.getText().equals("")&&message.getValue().equals(JOptionPane.OK_OPTION)){
Toolkit.getDefaultToolkit().beep();
message.setValue(JOptionPane.UNINITIALIZED_VALUE);
return;
}
query.dispose();
}
}
});
query.pack();
query.setVisible(true);
if(Integer.parseInt(message.getValue().toString())==JOptionPane.OK_OPTION){
players.add(new Player(nameField.getText(),(Sport)major.getSelectedItem()));
edited=true;
}
gui.show(players);
}
});

I don't think you can do it with JOptionPane but you can using using TaskDialog framework and few others.
You can also create a dialog yourself, attach change listeners to your fields and enable/disable OK button based on content of your fields. This process is usually called "form validation"

However, I want to stop the user from closing the dialog while the
text field is blank
I get where you are going, but Java Swing is not very good at this. There is no way you can prevent the listener from being called. A solution would be to ignore the call, but this is complicated to implement.
The way I solved this issue is to let the pop-up disappear, check the returned value and if it is null/empty, beep and re-open it until user fills something.

JOptionPane does not internally support validation of inputs (Bug Reference). Your best bet is to create your own custom JDialog which supports disabling the OK button when the input data is invalid.
I'd recommend reading the bug report since other people talk about it and give workarounds.

However, I want to stop the user from closing the dialog while the text field is blank
The CustomDialog example from the section in the Swing tutorial on Stopping Automatic Dialog Closing has a working example that does this.
After taking a quick look at your code and the working example I think your code should be something like:
if (query.isVisible()
&& (e.getSource() == message)
&& (prop.equals(JOptionPane.VALUE_PROPERTY)))
{
if (message.getValue() == JOptionPane.UNINITIALIZED_VALUE)
return;
if (nameField.getText().equals("")
&& message.getValue().equals(JOptionPane.OK_OPTION))
{
Toolkit.getDefaultToolkit().beep();
message.setValue(JOptionPane.UNINITIALIZED_VALUE);
}
else
query.dispose();
}
Otherwise, I'll let you compare your code with the working code to see what the difference is.

One way to solve this problem is to add a Cancel and Ok button to your dialog. Then, disable closing the popup via the X in the corner, forcing the user to click either Cancel or Ok to finish/close the dialog. Now, simply add a listener to the text field that will disable the Ok button if the text field is blank.
Judging from your code I assume you can figure out how to implement these steps, but if you have trouble let us know! Good luck!

How show my application delay with JProgressBar?

I wrote a simple application and I want show delay of it with JProgressBar Plese help me ;
I want show JProgressBar with Joptionpane , with a cancel button and it should be modal
this is my source code :
class CustomFrame extends JFrame {
private JProgressBar progressBar;
public CustomFrame() {
long start = System.currentTimeMillis();
myMethod();
this.getContentPane().setLayout(null);
this.setSize(200, 200);
//JOptionPane. ?????
this.setTitle("JFrame");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
long end = System.currentTimeMillis();
System.out.print("\nTime: " + (end - start));
}
public void myMethod(){
try {
java.io.File file = new java.io.File("i://m.txt");
BufferedReader input =
new BufferedReader(new FileReader(file));
String line;
while ((line = input.readLine()) != null) {
if (line.indexOf("CREATE KGCGI=") != -1 ){
System.out.println(line);
}
}
input.close();
}
catch(Exception e){
e.printStackTrace();
}
}
Thanks ...

There are a couple things that you will need to do to get this to work:
You should be aware of threading issues in Swing. Your GUI painting should be done on the EventDispatchThread and disk I/O should be done in a worker thread. See this tutorial, the SwingWorker JavaDoc, and SwingUtilities.invokeLater for more detail
You will then want to get the size of your file (file.length())to determine how to scope your progress bar (myProgressBar.setMaximum(length))
When you iterate over the lines in your file, you will want to trigger an update to your progress bar (myProgressBar.setValue(myProgressBar.getValue()+lineLength)).
A couple points by way of critique:
your constructor shouldn't go off and do all of your work (ie load your file and pop up an option pane with the ability to cancel. the constructor should just do the work needed to create the object. you might want to consider having your constructor create your class, and then have the work that needs to be done to be called separately, or within something like an init() method.
It isn't clear what you are doing with the JFrame as superclass. JOptionPane is a class that will pop up a very basic modal dialog with some text, maybe an icon or input field. It isnt a panel that is embedded in a dialog.
As JOptionPane is a very basic construct for creating a basic message dialog, it might be easier to use a JDialog, which can also be made modal. JDialog will allow you to add buttons as you please, where as a standalone JOptionPane will require you to use Yes/No, or Yes/No/Cancel or OK/Cancel etc.
If you still want to use JOptionPane, and only show a cancel button, you can instantiate a JOptionPane (as opposed to using the utility show* methods), with the progressbar as the message, and the JOptionPane.CANCEL_OPTION as the optionType param. You will still need to put this into a JDialog to make it visible. See this tutorial for more details:
JOptionPane (constructor)
Creates a JOptionPane with the specified buttons, icons, message, title, and so on. You must then add the option pane to a JDialog, register a property-change listener on the option pane, and show the dialog. See Stopping Automatic Dialog Closing for details.