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Java/Swing: Obtain Window/JFrame from inside a JPanel

How can I get the JFrame in which a JPanel is living?

My current solution is to ask the panel for it's parent (and so on) until I find a Window:

Container parent = this; // this is a JPanel
do {
    parent = parent.getParent();
} while (!(parent instanceof Window) && parent != null);
if (parent != null) {
    // found a parent Window
}

Is there a more elegant way, a method in the Standard Library may be?

Do something when the close button is clicked on a JFrame

Is there a way to somehow 'do something' when I click the red close button on the title bar of a JFrame? What I want to do is to call a method called confirmExit() when said button is clicked. So far, the only option I have is to have it do nothing, but I don't want that. How do I accomplish this?

Thanks in advance.

JFrame Exit on close Java

I don't get how can I employ this code:

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

to close the program with the x button.

Java - How to create a custom dialog box?

I have a button on a JFrame that when clicked I want a dialog box to popup with multiple text areas for user input. I have been looking all around to try to figure out how to do this but I keep on getting more confused. Can anyone help?

Is this the only way to teach a Java Frame something about the Aero Snap feature of Windows?

If I minimize a JFrame which was Aero-snapped to the left of the screen by clicking on the minimize-button of the Windows WindowDecoration and unminimize it by Alt-Tabbing or clicking it in the Windows TaskBar, the frame gets restored correctly snapped to the left. Good!

But if I minimize the frame by

setExtendedState( getExtendedState() | Frame.ICONIFIED );

and look at the preview by hovering over the Windows TaskBar, it shows the frame a wrong position. After unminimizing it by Alt-Tabbing or clicking it in the Windows TaskBar, the frame gets restored at this wrong position and size. The frame-bounds are the "unsnapped" values, which Windows normally remembers to restore if you drag the frame away from the ScreenBorder.

A screen recording of the Bug:

My conclusion is, that Java does not know about AeroSnap and delivers the wrong bounds to Windows. (For example Toolkit.getDefaultToolkit().isFrameStateSupported( Frame.MAXIMIZED_VERT ) ); returns false.)

This is my fix for the bug:

import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.Point;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;

/**
 * Fix for the "Frame does not know the AeroSnap feature of Windows"-Bug.
 *
 * @author bobndrew 20160106
 */
public class SwingFrameStateWindowsAeroSnapBug extends JFrame
{
  Point     location = null;
  Dimension size     = null;


  public SwingFrameStateWindowsAeroSnapBug( final String title )
  {
    super( title );
    initUI();
  }

  private void initUI()
  {
    setDefaultCloseOperation( EXIT_ON_CLOSE );
    setLayout( new FlowLayout() );
    final JButton minimize = new JButton( "Minimize" );
    final JButton maximize = new JButton( "Maximize" );
    final JButton normal = new JButton( "Normal" );
    add( normal );
    add( minimize );
    add( maximize );
    pack();
    setSize( 200, 200 );


    final ActionListener listener = actionEvent ->
    {
      if ( actionEvent.getSource() == normal )
      {
        setExtendedState( Frame.NORMAL );
      }
      else if ( actionEvent.getSource() == minimize )
      {
        //Size and Location have to be saved here, before the minimizing of an AeroSnapped WindowsWindow leads to wrong values:
        location = getLocation();
        size = getSize();
        System.out.println( "saving location (before iconify) " + size + " and " + location );

        setExtendedState( getExtendedState() | Frame.ICONIFIED );//used "getExtendedState() |" to preserve the MAXIMIZED_BOTH state

        //does not fix the bug; needs a Window-Drag after DeMinimzing before the size is applied:
        //          setSize( size );
        //          setLocation( location );
      }
      else if ( actionEvent.getSource() == maximize )
      {
        setExtendedState( getExtendedState() | Frame.MAXIMIZED_BOTH );
      }
    };

    minimize.addActionListener( listener );
    maximize.addActionListener( listener );
    normal.addActionListener( listener );

    addWindowStateListener( windowEvent ->
    {
      System.out.println( "oldState=" + windowEvent.getOldState() + "  newState=" + windowEvent.getNewState() );

      if ( size != null && location != null )
      {
        if ( windowEvent.getOldState() == Frame.ICONIFIED )
        {
          System.out.println( "Fixing (possibly) wrong size and location on de-iconifying to " + size + " and " + location + "\n" );
          setSize( size );
          setLocation( location );

          //Size and Location should only be applied once. Set NULL to avoid a wrong DeMinimizing of a following Windows-Decoration-Button-Minimize!
          size = null;
          location = null;
        }
        else if ( windowEvent.getOldState() == (Frame.ICONIFIED | Frame.MAXIMIZED_BOTH) )
        {
          System.out.println( "Set size and location to NULL (old values: " + size + " and " + location + ")" );
          //Size and Location does not have to be applied, Java can handle the MAXIMIZED_BOTH state. Set NULL to avoid a wrong DeMinimizing of a following Windows-Decoration-Button-Minimize!
          size = null;
          location = null;
        }
      }

    } );
  }


  public static void main( final String[] args )
  {
    SwingUtilities.invokeLater( new Runnable()
    {
      @Override
      public void run()
      {
        new SwingFrameStateWindowsAeroSnapBug( "AeroSnap and the Frame State" ).setVisible( true );
      }
    } );
  }
}

This seems to work for all situations under Windows7, but it feels like too much messing around with the window-management. And I avoided to test this under Linux or MacOS for some reason ;-)

Is there a better way to let AeroSnap and Java Frames work together?

Edit:

I've filed a bug at Oracle: http://bugs.java.com/bugdatabase/view_bug.do?bug_id=8147840

Show JFrame in a specific screen in dual monitor configuration

I have a dual monitor config and I want to run my GUI in a specific monitor if it is found. I tried to create my JFrame window passing a GraphicConfiguration object of my screen device, but it doesn't work, frame still display on the main screen.

How can I set the screen where my frame must be displayed?

Close one JFrame without closing another?

I want to display two (or more) JFrames at the same time.
When I close one of them (use the default close button), the other frames should still be visible.

How can I do that?

What is the difference between a JFrame and a JDialog?

What is the difference between a JFrame and a JDialog?

Why can't we use setDefaultCloseOperation(JDialog.EXIT_ON_CLOSE); for a JDialog?

JPanel vs JFrame in Java

I am learning Java gui. The way I learned to create a windows is to inherit or Extend JFrame class and I good to as JFrame contains all the properties of a Window. Now If I want to add something to this window, I need to use add() method. But Today I came across JPanel which also creates a windows and we can add stuff by jpanelObjec.add().

What is the difference between the two methods? Are they somehow related?

How to maximize a JFrame through code?

How to maximize a JFrame through code?

How to make a JFrame Modal in Swing java

I have created one GUI in which I have used a JFrame. How should I make it Modal?

The Use of Multiple JFrames, Good/Bad Practice? [closed]

I'm developing an application which displays images, and plays sounds from a database. I'm trying to decide, whether to use a separate JFrame to add Images to the Database from the GUI. I'm just wondering whether it is good practice to use multiple JFrames?

How to programmatically close a JFrame

What's the correct way to get a JFrame to close, the same as if the user had hit the [x] button, or pressed Alt+F4 (on windows)?

I have my default close operation set the way I want, via

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

and it does exactly what I want, with the aforementioned controls. This question isn't about that.

What I really want to do is cause the gui to behave in the same way as a press of [x] would cause it to behave.

I.e., supposing I were to extend WindowAdaptor, and then add an instance of my adaptor as a listener via addWindowListener(); I would like to see the same sequence of calls through windowDeactivated() windowClosing() windowClosed() as would occur with the [x]. Not so much tearing up the window as telling it to tear itself up, so to speak.

How to set JFrame to appear centered, regardless of monitor resolution?

While working with Java, I find it hard to position my main window in the center of the screen when I start the application.

Is there any way I can do that? It doesn't have to be vertically centered, horizontal alignment is the more important goal for me. But vertical alignment is also welcome.

Difference between JPanel, JFrame, JComponent, and JApplet

im making a physics simulator for fun and i was looking up graphics tutorials when i tried to figure out the difference between all these J's. could somebody elaborate on them or perhaps provide a link to a helpful source?