SWT Java Tutorial

Shells can generate a unique type of event: shell events (ShellEvent).
A shell event is generated when a shell is minimized, maximized, activated, deactivated, or closed.
To add a shell listener to a shell, use this method:

public void addShellListener(ShellListener listener)
To remove a shell listener from a shell, use this method:

public void removeShellListener(ShellListener listener)

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ShellEvent;
import org.eclipse.swt.events.ShellListener;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
public class ShellEvents {
  public static void main(String[] args) {
    final Display display = new Display();
    final Shell shell = new Shell(display, SWT.SHELL_TRIM);
    shell.setLayout(new FillLayout());
    shell.addShellListener(new ShellListener() {
      public void shellActivated(ShellEvent event) {
        System.out.println("activate");
      }
      public void shellClosed(ShellEvent arg0) {
        System.out.println("close");
      }
      public void shellDeactivated(ShellEvent arg0) {
      }
      public void shellDeiconified(ShellEvent arg0) {
      }
      public void shellIconified(ShellEvent arg0) {
      }
    });
    shell.open();
    // Set up the event loop.
    while (!shell.isDisposed()) {
      if (!display.readAndDispatch()) {
        // If no more entries in event queue
        display.sleep();
      }
    }
    display.dispose();
  }
}