This article will show you how to close a window in Java. Closing a window is much easier using Swing's JFrame
, but it's also doable using AWT's Frame
.
EditSteps
EditUsing javax.swing.JFrame
-
Obtain an instance of a
JFrame
, or create a new one. -
Set default close operation. Default close operation is set using the setter method inside the
JFrame
classsetDefaultCloseOperation
that determines what happens when the close button is clicked and takes the following parameters:WindowConstants.EXIT_ON_CLOSE
- Closes the frame and terminates the execution of the program.WindowConstants.DISPOSE_ON_CLOSE
- Closes the frame and does not necessarily terminate the execution of the program.WindowConstants.HIDE_ON_CLOSE
- Makes the frame appear like it closed by setting its visibility property to false. The difference betweenHIDE_ON_CLOSE
andDISPOSE_ON_CLOSE
is that the latter releases all of the resources used by the frame and its components.WindowConstants.DO_NOTHING_ON_CLOSE
- Does nothing when the close button is pressed. Useful if you wish to, for example, display a confirmation dialog before the window is closed. You can do that by adding aWindowListener
to the frame and overridingwindowClosing
method. Example of the custom close operation:frame.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE); frame.addWindowListener(new WindowAdapter() { @Override public void windowClosing(WindowEvent e) { // Ask for confirmation before terminating the program. int option = JOptionPane.showConfirmDialog( frame, "Are you sure you want to close the application?", "Close Confirmation", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE); if (option == JOptionPane.YES_OPTION) { System.exit(0); } } });
EditUsing java.awt.Frame
-
Obtain an instance of a
Frame
, or create a new one. -
Add window listener. Call
addWindowListener
method on the instance. The required argument isWindowListener
. You can either implement every method of theWindowListener
interface or override only the methods you need fromWindowAdapter
class. -
Handle window closing event. Implement
windowClosing
method fromWindowListener
interface or override it fromWindowAdapter
class. There are two ways of closing a window:- Dispose the window after the close button is clicked:
- Call
dispose
method insidewindowClosing
method. -
frame.addWindowListener(new WindowAdapter() { @Override public void windowClosing(WindowEvent e) { // Dispose the window after the close button is clicked. dispose(); } });
- Call
- Terminate the program after the close button is clicked:
- Call
System.exit
method insidewindowClosing
method. -
frame.addWindowListener(new WindowAdapter() { @Override public void windowClosing(WindowEvent e) { // Terminate the program after the close button is clicked. System.exit(0); } });
- Call
- Dispose the window after the close button is clicked:
EditTips
- Swing is preferred over AWT since the latter is really outdated.
- Using
WindowAdapter
you don't have to implement each and every methodWindowListener
contract tells us to, but only the ones we need.
EditRelated wikiHows
- Download Java to Internet Explorer
- Check Null in Java
- Create a New Java Project in Eclipse
- Get the Length of a String in Java
source How to of the Day http://ift.tt/2ajU4ja
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