Browser Close Event? Onunload?

[ReuDa]

Hi there,

I am using SmartGWT 3.0 and I wonder if there is a possibility to do something before a User closes the Browser Window. (Something like onUnload in JS)

This must not be a 100% solution. I have to invalidate a host-session. My fallback solution is to use a HttpSessionListener to do this, but it would be nice to do this immediately after a User closes the Browser window.

Thank you!

[shortpasta]

You could do this:
1. Periodically send a KeepAlive message to the server (say every 5 minutes) so that the server knows that the Browser is up
2. Server-side job that marks the browser session as completed, if no KeepAlive message was received within 6 minutes
3. The following code to catch the browser closing (will not catch browser GPF'ing or connections dying), to handle the majority case:

import com.google.gwt.event.logical.shared.CloseHandler;
import com.google.gwt.event.logical.shared.CloseEvent;

final CloseHandler closeHandler = new CloseHandler () {
  public void onClose (final CloseEvent closeEvent) {
    // tell the server i am going away
  }
};
com.google.gwt.user.client.Window.addCloseHandler (closeHandler);

4. The HttpSessionListener catch-all (though this should not be needed because of #2). Plus it might not kick in until the session expires, which could be a very long time...

Or just do #3

[ReuDa]

final CloseHandler closeHandler = new CloseHandler () {
  public void onClose (final CloseEvent closeEvent) {
    // tell the server i am going away
  }
};
com.google.gwt.user.client.Window.addCloseHandler (closeHandler);

That's it! Thank you very much....