How do I make non-modal dialog whose setVisible blocks? - java

In a Swing (J)Dialog, setModal sets the modality - that is, whether the dialog should block input to other windows or not. Then, setVisible docs say for modal dialogs:
If the dialog is not already visible, this call will not return until the dialog is hidden by calling setVisible(false) or dispose.
Indeed, setVisible does return right away if the dialog is not modal. Sample code:
JDialog jd = new JDialog();
jd.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
/**
* If set to false, setVisible returns right away.
* If set to true, setVisible blocks until dialog is disposed.
*/
jd.setModal(false);
System.out.println("setting visible");
jd.setVisible(true);
System.out.println("set visible returned");
I want to make a dialog that doesn't block input to other windows, but still does block the caller. What is a good way to do this, now that setVisible doesn't block when the dialog is not modal?
Is there some rationale why setVisible's behavior depends on the modality?

I need to make a dialog that doesn't block input to other windows, but does block the caller so that I know when the dialog has been closed.
I usually solve this not by blocking the caller, but by using a callback of some sort - a simple interface that the dialog invokes when it's done. Let's say your dialog has an "OK" and a "Cancel" button and you need to distinguish which one is pressed. Then you could do something like this:
public interface DialogCallback {
void ok();
void cancel();
}
public class MyModelessDialog extends JDialog {
private final DialogCallback cbk;
private JButton okButton, cancelButton;
public MyModelessDialog(DialogCallback callback) {
cbk = callback;
setModalityType(ModalityType.MODELESS);
okButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
onOK();
}
};
cancelButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
onCancel();
}
};
// Treat closing the dialog the same as pressing "Cancel":
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
onCancel();
}
};
}
private void onOK() {
cbk.ok();
}
private void onCancel() {
cbk.cancel();
}
}
Then you just pass in an instance of DialogCallback to the constructor:
MyModelessDialog dlg = new MyModelessDialog(new DialogCallback() {
public void onOK() {
// react to OK
}
public void onCancel() {
// react to Cancel
}
});
EDIT
Is there some rationale why setVisible's behavior depends on the modality?
Well, that's just how how modal windows are supposed to work, no? A modal window should block the current workflow when displayed, and a non-modal/modeless should not. See e.g. the Wikipedia pages on modal windows or dialog boxes.

Just put this.setModal(true) but not set the parent dialog on the constructor:
MyDialog dlg = new JDialog();
this.setModal(true);
When you call setVisible(true), it wont stop

The direct approach is by:
JDialog dialog = new JDialog(owner, ModalityType.DOCUMENT_MODAL);

I have found another way to do this. In the constructor of my progress bar, which extends javax.swing.JDialog, I added:
setModalityType(ModalityType.APPLICATION_MODAL);
I then overrode the setVisible method:
#Override
public void setVisible(boolean b) {
if (b) {
new Thread(new Runnable() {
#Override
public void run() {
showProgress();
}
}).start();
} else {
super.setVisible(false);
}
}
In the run(), you can see a call to showProgress(). This simply is:
public void showProgress() {
super.setVisible(true);
}
What happens here, is the setVisible() method of JDialog blocks. So I overrode it, and called setVisible() of the JDialog, in a thread. Resulting in it not blocking.

Related

how do I make this window close in java?

I've already this project, but I'm having more problems. The dialog for SetMusicDialog opens, but it won't close when I try to exit out. I have a System.exit, but I'm not sure why the window won't close.
import java.awt.*;
import java.io.*;
public class SetMusicDialog extends Dialog
{
public static String sng;
public SetMusicDialog()
{
super ((Dialog)null, "Set Music");
Panel mpanel;
Font l = new Font("Helvetica", Font.ITALIC, 12);
setFont(l);//sets font
setBackground(Color.cyan);
Panel f = new Panel();
f.add("West", new Button("Death Grips"));
f.add("East", new Button("Siren"));
add("South",f);
pack(); // make it just fit
resize(preferredSize());
move(200,200);
}
public boolean handleEvent1 (Event evt)
{
switch (evt.id)
{
case Event.WINDOW_DESTROY:
System.exit(0);
dispose();
return true;
case Event.ACTION_EVENT:
if("Death Grips".equals(evt.arg))
{
sng= "breakmirrors.wav";
}
else if("Siren".equals(evt.arg))
{
sng= "bip.wav";
}
dispose();
}
return false;
}
}
You can add this:
addWindowListener( new WindowAdapter() {
public void windowClosing(WindowEvent e){
dispose();
System.exit(0);
}
});
windowClosed won't detect if the user tries to close the window. It will only run if the window has been closed. So use windowClosing.
Also, by using WindowAdapter you do not need to write all the methods of WindowListener.
I added this code in your constructor, and it works properly.
If you are using AWT, you should create a WindowListener as MadProgrammer stated. Basically, a WindowListener is a class that has methods that are run when certain window-related actions occur. To write code that will run when a Dialog (which extends Window) is closed:
//d is a dialog
d.addWindowListener(new WindowListener() {
//You'll need to implement all the abstract methods. leave them empty.
#Override
public void windowClosed(WindowEvent e) {
//Your code
}
});
Basically, you're anonymously implementing the abstract class WindowEvent. Make sure you implement all the other methods too, or you will get compiler errors. Your IDE should automatically implement all the methods.

JFrame-JDialog comunication

I have a JFrame main window wich has a Register button on in.Click the register button and the JDialog windows pops out.
public void mouseClicked(MouseEvent e) {
Reg new1=new Reg(users);
new1.setVisible(true);
}
The JDialog window has 2 buttons->Register,Cancel.Both of them must do something and close the Dialog window.
This is what I tried.
In the Reg(Dialog window)---> btnCancel:
public void mouseClicked(MouseEvent e) {
dialog.dispose();
System.out.println("Reg disposed by cancel button");
}
This closes the D window when run just the D window but I guess when executed from the main window(Button clicked) it still exists like an object in the main fraim"class" and doesn't close.What should I do ?How do I make it close ?
You need some way for the frame to determine how the dialog was closed
// Why are you using a `MouseListener` on buttons??
// User use keyboards to, use an ActionListener instead
public void mouseClicked(MouseEvent e) {
Reg new1=new Reg(users);
new1.setVisible(true);
switch (new1.getDisposeState()) {
case Reg.OK:
// Clicked Ok
break;
case Reg.CANCEL:
// Clicked cancel or was closed by press [x]
break;
}
}
Then in your Reg class, you need to maintain information about the state...
public class Reg extends JDialog {
public static final int OK = 0;
public static final int CANCEL = 1;
private int disposeState = CANCEL;
//...
public int getDisposeState() {
return disposeState
}
public void setDisposeState(int state) {
disposeState = state;
}
Then you change the state
// Why are you using a `MouseListener` on buttons??
// User use keyboards to, use an ActionListener instead
public void mouseClicked(MouseEvent e) {
setDisposeState(CANCEL);
dialog.dispose();
System.out.println("Reg disposed by cancel button");
}
This all assumes that your dialog is modal of course...
Now, having said all that, personally, I would make your Reg class a JPanel and add it to a JOptionPane instead or use a CardLayout
Take a look at:
How to Use Buttons, Check Boxes, and Radio Buttons
How to Write an Action Listeners
How to Make Dialogs
How to Use CardLayout
...for more details

Closing A JOptionPane Programmatically

I am working on a project in which I would like to close a generic JOptionPane programmatically (by not physically clicking on any buttons). When a timer expires, I would like to close any possible JOptionPane that may be open and kick the user back to the login screen of my program. I can kick the user back just fine, but the JOptionPane remains unless I physically click a button on it.
I have looked on many sites with no such luck. A doClick() method call on the "Red X" of the JOptionPane does not seem possible, and using JOptionpane.getRootFrame().dispose() does not work.
Technically, you can loop through all windows of the application, check is they are of type JDialog and have a child of type JOptionPane, and dispose the dialog if so:
Action showOptionPane = new AbstractAction("show me pane!") {
#Override
public void actionPerformed(ActionEvent e) {
createCloseTimer(3).start();
JOptionPane.showMessageDialog((Component) e.getSource(), "nothing to do!");
}
private Timer createCloseTimer(int seconds) {
ActionListener close = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
Window[] windows = Window.getWindows();
for (Window window : windows) {
if (window instanceof JDialog) {
JDialog dialog = (JDialog) window;
if (dialog.getContentPane().getComponentCount() == 1
&& dialog.getContentPane().getComponent(0) instanceof JOptionPane){
dialog.dispose();
}
}
}
}
};
Timer t = new Timer(seconds * 1000, close);
t.setRepeats(false);
return t;
}
};
This code gotten from
https://amp.reddit.com/r/javahelp/comments/36dv3t/how_to_close_this_joptionpane_using_code/ seems to be the best approach to me. It involves Instantiating the JOptionPane class rather that using the static helper methods to do it for you. The benefit is you have a JOptionPane object that you can dispose when you want to close the dialog.
JOptionPane jop = new JOptionPane();
jop.setMessageType(JOptionPane.PLAIN_MESSAGE);
jop.setMessage("Hello World");
JDialog dialog = jop.createDialog(null, "Message");
// Set a 2 second timer
new Thread(new Runnable() {
#Override
public void run() {
try {
Thread.sleep(2000);
} catch (Exception e) {
}
dialog.dispose();
}
}).start();
dialog.setVisible(true);

Detecting Approval button in a Swing FileChooser event

I know that there is another way to do this, but I prefer to see if anyone has an answer for doing it this way. The original way is to get the integer return value after calling the ShowDialog() function; I want to grab it from within the Event (shown below) itself. I've thrown some code in there to check if a file is selected, but I need to check whether the approval button (the OK button) has been selected before it gets there. Does anyone know how to check which button is pressed in a FileChooser dialog, using a setup like below?
Here's my code:
private void FileChooser_OpenMouseClicked(java.awt.event.MouseEvent evt) {
if(!FileChooser_Open.getSelectedFile().equals(null))
{
}
}
Original method:
//In response to a button click:
int returnVal = fc.showOpenDialog(aComponent);
The difference is that the original method gets a return value when the dialog box is closed, while in this method, I do not know of a way to get that return value (I believe the box has already closed, but there is nothing there to catch the return value). I apologize if I do not appear to be making a lot of sense.
edit: More information
So this is how I am creating the dialogue (a menu item, "Open" raises an event, which calls the showOpenDialog() method. As you can see, it is not capturing the return value (bear with me). Is it possible then to get the return value or at design a method to figure out whether the OK button is then pressed in the MouseClicked event? I guess I am trying to focus on an event-based programming style, where the code reacts according to the event raised, and grabbing the checking for the OK / approval button click inside the Open Menu event seems a little...disorganized from my perspective. Perhaps I am too used to C# / WinForm's approach to this problem?
private void MenuItem_OpenActionPerformed(java.awt.event.ActionEvent evt) {
FileChooser_Open.showOpenDialog(this);
}
private void FileChooser_OpenMouseClicked(java.awt.event.MouseEvent evt) {
if(!FileChooser_Open.getSelectedFile().equals(null))
{
}
}
If I understand the question, you might be able to use a JFileChooser#approveSelection() method:
OTN Discussion Forums : How to react on events fired by a JFileChooser?
java - JFileChooser with confirmation dialog - Stack Overflow
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;
public class ApproveSelectionDemo {
public JComponent makeUI() {
final JPanel p = new JPanel();
final JFileChooser fileChooser = new JFileChooser() {
#Override public void approveSelection() {
if(!getSelectedFile().exists()) {
int returnVal = JOptionPane.showConfirmDialog(
this, "message", "title", JOptionPane.YES_NO_OPTION);
if(returnVal!=JOptionPane.YES_OPTION) {
return;
}
}
super.approveSelection();
}
};
p.add(new JButton(new AbstractAction("Open") {
#Override public void actionPerformed(ActionEvent e) {
int retvalue = fileChooser.showOpenDialog(p);
if(retvalue==JFileChooser.APPROVE_OPTION) {
System.out.println(fileChooser.getSelectedFile());
}
}
}));
return p;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override public void run() {
createAndShowGUI();
}
});
}
public static void createAndShowGUI() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
f.getContentPane().add(new ApproveSelectionDemo().makeUI());
f.setSize(320, 240);
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}

removing focus from JDialog if main application is minimised

I have a JDialog which popup whenever my main application recieves an event.
The problem I'm facing is that the dialog pops up evenif the main window is minimised. A similar question was asked here but no answer was given as to how to solve this except a link to sun's guide on focus handling Hide JDialog window when the window lost focus.
Suppose I have the function createandshowDialog() such as
public void createAndShowDialog(boolean manualLaunch) {
if (manualLaunch || shouldShowMessage()) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
if (dialog == null) {
dialog = new xyzDialog(getPendingList());
}
GUIHelper.flash(PLAFHelper.getMainFrame(), true, false);
dialog.setVisible(true);
}
});
}
}
And the xyzDialog class is defined as :
public class xyzDialog extends SimpleStandardDialog
{
protected final static Log logger = LogFactory.getLog(xyzDialog.class);
private xyzPanel panel;
public xyzDialog(ObjectArrayList list) {
super(PLAFHelper.getMainFrame(), "Pending Cancel/Replace");
initializeLocalVars();
panel = new xyzPanel(list, mediator);
super.setSize(750,600);
setResizable(true);
setDefaultCloseOperation(DO_NOTHING_ON_CLOSE);
setModal(false);//todo: for testing...
if(PUMAGUIOptions.cFocusOnxyzPopup){
setFocusableWindowState(true);
validate();
}
else{
setFocusableWindowState(false);
validate();
}
}
The default behaviour should be such that it should not popup if main window is minimised or we explicitly set cFocusOnxyzPopup as false to force this default behaviour (which is the case when it is open on say secondary monitor and we are working on primary monitor or application is maximised or is in background i.e. is not the focusOwner.
I have set focusableWindowState as false so that it would not satisy the condition for gaining focus and return isFocusable as false if invoked as given in java-docs. But this is not working. Any suggestions?
USe JFrame's method
public synchronized int getExtendedState()
e.g. PLAFHelper.getMainFrame().getExtendedState()
if it's JFrame.ICONIFIED skip the dialog opening.
I have meet the same problem and search the stackoverflow ! finally, I find out the
corrent answer answered by Markus Lausberg in
JDialog lets main application lose focus
just calling the following method during dialog create:
setFocusableWindowState(false);
setFocusable(false);

Categories