A WindowEvent is sent by a Browser when a new window needs to be created or when an existing window needs to be closed. This notification occurs when a javascript command such as window.open or window.close gets executed by a Browser.

The following example shows how WindowEvent's are typically handled.

	public static void main(String[] args) {
		Display display = new Display();
		Shell shell = new Shell(display);
		shell.setText("Main Window");
		shell.setLayout(new FillLayout());
		Browser browser = new Browser(shell, SWT.NONE);
		initialize(display, browser);
		shell.open();
		browser.setUrl("http://www.eclipse.org");
		while (!shell.isDisposed()) {
			if (!display.readAndDispatch())
				display.sleep();
		}
		display.dispose();
	}

	static void initialize(final Display display, Browser browser) {
		browser.addOpenWindowListener(new OpenWindowListener() {
			public void open(WindowEvent event) {
				// Certain platforms can provide a default full browser.
				// simply return in that case if the application prefers
				// the default full browser to the embedded one set below.
				if (!event.required) return;

				// Embed the new window
				Shell shell = new Shell(display);
				shell.setText("New Window");
				shell.setLayout(new FillLayout());
				Browser browser = new Browser(shell, SWT.NONE);
				initialize(display, browser);
				event.browser = browser;
			}
		});
		browser.addVisibilityWindowListener(new VisibilityWindowListener() {
			public void hide(WindowEvent event) {
				Browser browser = (Browser)event.widget;
				Shell shell = browser.getShell();
				shell.setVisible(false);
			}
			public void show(WindowEvent event) {
				Browser browser = (Browser)event.widget;
				Shell shell = browser.getShell();
				if (event.location != null) shell.setLocation(event.location);
				if (event.size != null) {
					Point size = event.size;
					shell.setSize(shell.computeSize(size.x, size.y));
				}
				if (event.addressBar || event.menuBar || event.statusBar || event.toolBar) {
					// Create widgets for the address bar, menu bar, status bar and/or tool bar
					// leave enough space in the Shell to accommodate a Browser of the size
					// given by event.size
				}
				shell.open();
			}
		});
		browser.addCloseWindowListener(new CloseWindowListener() {
			public void close(WindowEvent event) {
				Browser browser = (Browser)event.widget;
				Shell shell = browser.getShell();
				shell.close();
			}
		});
	}
 

The following notifications are emitted when the user selects a hyperlink that targets a new window or as the result of a javascript that executes window.open.

Main Browser

• User selects a link that opens in a new window or javascript requests a new window
• OpenWindowListener.open() notified
  • Application creates a new Shell and a second Browser inside that Shell
  • Application registers WindowListener's on that second Browser, such as VisibilityWindowListener
  • Application returns the second Browser as the host for the new window content

Second Browser

• VisibilityWindowListener.show() notified
  • Application sets navigation tool bar, status bar, menu bar and Shell size
  • Application makes the Shell hosting the second Browser visible
  • User now sees the new window