I have a multiple JPanels which are put in a dialogue and after many hours, I am still unable to find the frame in which the JPanels are stored in. I was wondering if there is a method which would return the JFrame (end goal is to call setDefaultCloseOperation() on the JFrame). I was thinking getParent() would do this however I am still unable to call setDefaultCloseOperation no matter how many layers of parents I go through.
There is a utility method for it:
SwingUtilities.getWindowAncestor()
If you add your JPanel to a JFrame, it will be obviously a JFrame instance:
JFrame f = (JFrame) SwingUtilities.getWindowAncestor(panel);
Note: getWindowAncestor() and windowForComponent() provide the same functionality.
Window window = SwingUtilities.windowForComponent(...);
Related
I've searched and could not find the answer I need to do the following: I have two java files: one JFrame, one JPanel. I configured a button in the JFrame to open up the JPanel from within the main frame with a new size of 800,800. Now, I want to close the JPanel and go back to the original JFrame (the one that originally was at size 500,500 with an image). It seems simply straightforward, but I've created an instance of the main frame from within the JPanel and set the jPanel to (this.setVisible(false)). I created a new jFrame object and set its visibility to true. What happens is, a new instance of the JFrame appears alright, but the JFrame at 800,800 with no image still appears as well. I've tried several configurations of getContentPane(), setContentPane() and even tried passing a JFrame parameter to the constructor of the JPanel. I'm not sure where I am going wrong with this, but any help would be much appreciated. All I want is the original JFrame with the original size and image displayed. Thank you in advance.
private void jButton_closeActionPerformed(java.awt.event.ActionEvent evt) {
this.setVisible(false);
mainMenuFrame = new MainMenuFrame();
mainMenuFrame.setVisible(true);
invalidate(); validate();
repaint();
}
you could open and close the jpanel from within your JFrame. the button would be also added to the jframe instead of the jpanel. for easier accessing use the jpanel as member variable
I'm building a JPanel and it is given to a JInternalFrame. Now I want that if someone clicks on the X button of the JInternalFrame it is hidden, not closed. The Problem is that I have to implement this function in the JPanel and I don't have access to the JInternalFrame.
Is this possible?
I know from the JInternalFrame it can be realized with setDefaultCloseOperation(HIDE_ON_CLOSE); but I don't know how to do it from the JPanel. Of course I searched in SO but I did not found anything that fits for my case.
Another Question, just for understanding: what is happening when you click on the X button? Is the dispose() function called? I'm new to Java Swing and interested how it works.
but I don't know how to do it from the JPanel
You can use the SwingUtilities class to find the parent container.
Something like:
JInternalFrame frame = (JInternalFrame)SwingUtilities.ancestorOfClass(JInternalFrame.class, thePanel);
I have a main class in java which call a JFrame Two.
But before call this JFrame Two, my main check a condition and if it's true, it call a JFrame One.
So, my main don't extends JFrame.
I want that my JFrame One stop my main until it been closed, then my main could call my JFrame Two.
I tried to make my JFrame One as a JDialog modal, but my main still running (probably because it isn't a JFrame ?)
Here a simplified part of my code :
File file = new File(PTA);
if (!file.exists()) {
FrameOne fo = new FrameOne(); //FrameOne Extends JFrame
}
FrameTwo ft = new FrameTwo();
So like you can see, my main will always call FrameTwo.
But i want that until FrameOne was closed, the main class stop running, so it don't call FrameTwo until FrameOne was closed.
I don't really know how a JDialog works, i tried to convert my JFrameOne in a JDialog with "setModal(true)" but my main class still running too.
Please can you help me ? My project is blocked by this problem...
Thanks for your attention and your help.
Regards,
Maxime OZENNE.
i tried to convert my JFrameOne in a JDialog with "setModal(true)" but my main class still running too.
It doesn't work that way, you and you can't make a JFrame modal this way (the JFrame doesn't even have this method). Instead you're going to have to use a JDialog and not a JFrame, and create the dialog so that it's modal. Myself I avoid creating classes that extend JFrame or the like and instead gear my code towards creating JPanels, which can then be placed into JFrames or JDialogs, or JTabbedPanes, or swapped via CardLayouts, wherever needed. This will greatly increase the flexibility of your GUI coding.
So on that note, I'd do something on these lines:
MyPanel myPanel = new MyPanel();
// assuming that the parent window JFrame is referenced by "myFrame"
JDialog myDialog = new JDialog(myJFrame, "My Dialog", ModalityType.APPLICATION_MODAL);
myDialog.add(myPanel);
myDialog.pack();
myDialog.setVisible(true);
If this doesn't help, then please create and post your Minimal, Complete, and Verifiable example program, and let us help modify it.
How do I go about setting a JFrame class relative to another JFrame class?
I know that if I create a JFrame in the same class as the one I want to center I call setLocationRelativeTo(this), but due to the class getting long I cut it down into smaller JFrame classes.
So far i'm having to use setLocationRelativeTo(null) to center it but this is not very good when I want the JFrame that is popping up to be ontop of the main JFrame.
I have a very simple JFrame window that contains one button: No.
In the main function I set setVisible(true); my JFrame and in the No button listener I want to close the window so I set the visibility to false: setVisible(false); and after that I do System.exit(0); in order to prevent possible memory leaks when running the program many times.
I have two questions:
Do I really need to System.exit(0); in the above case?
If I have this JFrame as a popup window, I can't really use System.exit(0); because this will terminate the whole program. So how can I properly close the popup window and stay in the main JFrame window? (Now I close it only by setVisible(false); and when I do it several times through the program execution, the program turns very slow).
use CardLayout
if is there real reason for another popup container
use JDialog with parent to JFrame, with setModal / ModalityTypes
create only one JDialog and to reuse this one JDialog by getContentPane#removeAll()
use JOptionPane for simple users interaction
put both together, above two points, to use CardLayout for popup JDialog with parent to JFrame, notice after switch from one card to another could be / is required to call JDialog.pack()
setVisible will cause slowdown
dispose will cause slowdown
System.exit will close entire JVM
Therefore, you should reuse a single JFrame or JDialog.
In the button's ActionListener, invoke frame.setVisible(false);. Then instead of creating a new frame just do frame.setVisible(true);. If you want to change the contents of the frame, there is the function frame.getContentPane().removeAll();.
Just add this: JFrame.setDefaultCloseOperation(DISPOSE_ON_CLOSE).
Note: The default option for JFrame is HIDE_ON_CLOSE.
You can use the dispose() method of the JFrame class to close the frame and release all resources associated with it, including its child components.