I want to pop up a dialog box that says "Saving..." and once the operation is completed, it simply disappears. While the saving is in progress, I dont want the user to be able to do anything. I also dont want an OK button.
What is the name of the Java class that allows me to do this?
I think JDialog is what you want - be sure to call setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE) on it since unlike a JFrame, its default behaviour is HIDE_ON_CLOSE.
Here's the final code I found that roughly simulated what I wanted to do:
// Create dialog box
JDialog dialog = new JDialog(new JFrame(), "Saving...");
// IMPORTANT: setLocationRelativeTo(null) is called AFTER you setSize()
// otherwise, your dialog box will not be at the center of the screen!
dialog.setSize(200,200);
dialog.setLocationRelativeTo(null);
dialog.toFront(); // raise above other java windows
dialog.setVisible(true);
// Sleep for 2 seconds
try
{
Thread.sleep(2000);
} catch (InterruptedException ex)
{
Logger.getLogger(JavaDialogBox.class.getName()).log(Level.SEVERE, null, ex);
}
// Then "close" the dialog box
dialog.dispose();
Lastly, found these 3 links to be quite helpful when writing the above code:
Center the dialog to screen
How to create JDialog
How to pause execution
You might also consider using a javax.swing.JProgressBar within your dialog so you can show progress is happening. If you have enough information during the save process to give a percentage complete you can show that, and if not you can show it as indeterminate (moving back and forth until complete). Then dispose the dialog once the save process is complete -- this would be nice user experience enhancement over showing a static text message for a fixed amount of time. Here's a tutorial with demo Java code showing an example dialog: http://java.sun.com/docs/books/tutorial/uiswing/components/progress.html.
I think what you may want is a modal JDialog. They make it fairly easy to block user interaction for your whole application and you have some extra control.
The code snippet you posted will potentially have issues if your save operation takes longer than 2 seconds. I'd suggest calling your save() function in the place where you currently have the Thread.sleep(). That way, you know that no matter how long the save takes, the UI will be blocked.
Related
I need my JFrame to freeze/ become inaccessible, similar to how it would with a model JDialog or setEnabled(false).
In most cases I would use JDialog but in this instance I am running a dialog through a C library.
Going down the setEnabled(false) line also doesn't work because it, on setEnabled(true), will send the window to the back. And even using toFront() will cause the window to go to the back for a split second then come to the front again.
Is there a better way to go about doing this, or an I stuck with the slight imperfection of the window flickering.
Also if you are familiar with the library I am using LWJGL's NativeFileDialog wrapper.
I have found a pretty good solution to this issue, originally answered as part of this post. It takes the idea of using a JDialog, but instead of displaying some message it is completely transparent, invisible to the user.
final JDialog modalBlocker = new JDialog();
modalBlocker.setModal(true);
modalBlocker.setUndecorated(true);
modalBlocker.setOpacity(0.0f);
modalBlocker.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
Then we can simply display our modal and show our file dialog
// Using invoke later we show our dialog after our frame has been blocked
// by setVisible(true)
SwingUtilities.invokeLater(()->{
// show dialog
});
modalBlocker.setVisible(true);
modalBlocker.dispose(); // immediately release resources
Then we can call modalBlocker.setVisible(false) at any point to stop the modality effect on our frame.
Again this is the solution that worked for me, it is not mine. The code was written to integrate JavaFX with Swing by Sergei Tachenov, all credit goes to him!
Is there a possibility to prevent a JOptionPane dialog from blocking the interaction with the rest of the program, especially child JFrames? In my GUI, I launch a JFrame and want a message dialog to pop up after the child is closed to remind the user of something, but they launch parallel and the reminder blocks the child frame from being used.
Like here:
popupObjMan newPopup1 = new popupObjMan(gatewayAbstract, gatewayAbstractID);
JOptionPane.showInternalMessageDialog(this, "REMINDER: DO REFRESH");
I've tried to set the popup always on top, but this doesn't quite do the job.
I have no problem with them launching parallel (I'd even prefer it), but I could not work my head around it yet.
I just started Java programming ,so sorry in case that'd be something obvious.
A JOptionPane normally need to be modal. It shows something important and waits till the user answers with whatever option you give him (e.g. ok-button, yes/no-buttons, ...)
But there are several ways to reach your target.
(a)
Normally a JOptionPane creates a modal window.
You need a modeless window which does not block other windows.
https://docs.oracle.com/javase/tutorial/uiswing/misc/modality.html
(b)
You can start different threads to work for your different windows. They can have windows which are shown whenever the responsible thread commands them to. This is a bit difficult and can lead to memory-troubles.
(c)
You can write your own message-panels (e.g. notificaton) which are shown when and how long you like.
Bigger projects use different of these ways to achieve their goals.
A JOptionPane is a component, just like a JPanel. As a component it can be added to any other panel.
The JOptionPane API provides static methods to create a show the JOptionPane on a modal JDialog by default. You can't change this behaviour.
However, you can manually add the JOptionPane to a non-modal JDialog that you create. This is extra work as you now need to handle the closing of the dialog and processing the clicked button.
If you really want to do this then read the JOptionPane API. There is a section on Direct Use which demonstrates the basic code needed to add the JOptionPane to a JDialog.
I noticed a behavior that I can't explain. In my GUI, on a button click I display a custom Jdialog that has panel and bunch of textfield. I populate these textfields.
Here is the scenario I am seeing using pseduo code.
public void actionPerformed(ActionEvent e) {
CustomDialog viewDialog = new CustomDialog (Jframe, true);
viewDialog.setVisible(true);
viewDialog.populateInfo();
}
When the code above runs then all textfields are empty. However if I move the setVisible to after the populateInfo method then all the textFields are populated. Basically the JTextField.setText inside the populate info does not seem to have an affect if the setVisible happens before
Why is this!
Likely your CustomDialog class is a modal JDialog (also as suggested by the true 2nd constructor parameter). If so, then program flow in the calling code is blocked by the setVisible(true) call, and so your populateInfo() method will only be called after the dialog is no longer visible. The solution is as you already know -- call the method before displaying the dialog.
This is not a bug but a feature. :)
Seriously, since now you know for a fact when program code flow will be halted and when it will resume, and so you can safely query the dialog for its state after the setVisible(true) has been called, and feel confident that in the very least the dialog has been presented to the user, and the user has had time to interact with it and dispose of it.
I have a simple program that utilizes Java Swing Timer to display an image for 400 miliseconds, in this period of time I just want to stop all ActionListeners or stop taking ActionEvents. I've got 40+ buttons and want a simple way to do this.
Is there anyway to do that in Java?
Can you determine that you are in this "image displayed" state? The image goes up and you set the state to "image displayed" or whatever. Go through your widgets and decide which ones are supposed to be dead while the image is up. Turn them into Observers of this state value. When the state changes, they either enable or disable, as appropriate. The image code doesn't do anything directly to any widget. It just declares that the state is now "image displayed". It's up to the Observers to decide what to do, if anything, with that information.
Or use the GlassPane. That works too. Of course, the GlassPane shuts down everything. If you need to be more selective, you need a more fine-tuned approach.
You can use a temporary GlassPane instance to consume all events by registering empty listeners to it.
Use an undecorated modal JDialog to display the image. Before you make the dialog visible you would start a Timer. When the Timer fires in 400 ms you close the dialog.
I've had similar issues and typically found that its a design issue that got me in that situation. Being the case, I still had to find away around it. To fix the issue, I kept a list of the elements that I wanted to disable (stop listening) and iterated through them at the beginning and end of the timer. For buttons it should be as simple as:
for(Component c : listOfToggledComponents){
c.setEnabled(shouldItBeEnabled);
}
For buttons, this will grey out the button. Similar things happen to other swing components.
i have a small program where an element is draged and dropped, when the drop is performed i open a dialog (extends Jframe) where some text should be entered. The Problem is, that i want to wait for this dialog to be closed (actually the ok button to be pressed so i can read out the data from the textfield), than analyse what the user has entered and based on that i will decide if the drop is rejected or allowed.
public void drop(DropTargetDropEvent e) {
try{
//popup
Popup p = new Popup();
p.setParmeter("enter a new name: ");
p.setVisible(true);
//programm wont wait before the user has pressed ok in the popup
System.out.println("value: " + p.getValue());
repaint();
} else {
e.rejectDrop();
}
}
I hope you get the idea. Popup is a dialog extended from a JFrame. The problem is, that p.getValue() is executed before the User gets to press the ok button. I tried using a boolean variable and a loop to check if something was entered in the popup but it doesnt work, the dialog is desplayed but there is not textfield or ok button, so the only thing i can do is to kill it. I'm pretty new to gui's so i really would appreciate the help. Thanks in advance.
If possible you should re-implement Popup to inherit from JDialog instead of JFrame, and call JDialog's setModal(true) method, which will prevent subsequent code from running until the dialog is dismissed.
Alternatively, check out the static convenience methods in JOptionPane, which eliminate the need to implement your own bespoke dialog class in many cases. For example (from the JOptionPane API):
Show an information panel with the options yes/no and message 'choose one':
JOptionPane.showConfirmDialog(null, "choose one", "choose one", JOptionPane.YES_NO_OPTION);
Java has built-in dialog support. Yon don't want to extend JFrame. See the tutorial on how to make dialogs.