Package com.google.gwt.user.client

## Interface WindowCloseListener

- All Superinterfaces:
    `java.util.EventListener`

      @Deprecated
      public interface WindowCloseListener
      extends java.util.EventListener

  Deprecated.
  use `Window.ClosingHandler` and `CloseHandler` instead
  Implement this interface to receive closing events from the browser window.
  See Also:
    `Window.addWindowCloseListener(WindowCloseListener)`

- - ### Method Summary

    All Methods Instance Methods Abstract Methods Deprecated Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `onWindowClosed()` | Deprecated.
    `java.lang.String` | `onWindowClosing()` | Deprecated.

- - ### Method Detail

    - #### onWindowClosing

          @Deprecated
          java.lang.String onWindowClosing()

      Deprecated.
      Fired just before the browser window closes or navigates to a different site. No user-interface may be displayed during shutdown.
      Returns:
        non-`null` to present a confirmation dialog that asks the user whether or not she wishes to navigate away from the page. The string returned will be displayed in the close confirmation dialog box. If multiple listeners return messages, the first will be displayed; all others will be ignored.

    - #### onWindowClosed

          @Deprecated
          void onWindowClosed()

      Deprecated.
      Fired after the browser window closes or navigates to a different site. This event cannot be canceled, and is used mainly to clean up application state and/or save state to the server.