Re: [platform-swt-dev] in a sub thread, how to call a widget of its fath

[Carolyn MacLeod <Carolyn_MacLeod@xxxxxxxxxx>]

Thank-you, Dan.
Please open a bug report against Platform
- Doc.
Carolyn

Dan Kehn <kehn@xxxxxxxxxx>
Sent by: platform-swt-dev-admin@xxxxxxxxxxx

10/21/2004 10:57 AM

Please respond to
platform-swt-dev

To	platform-swt-dev@xxxxxxxxxxx
cc
Subject	Re: [platform-swt-dev] in a sub thread, how to call a widget of its father

The example cited in the online documentation should add a test:

   // do time-intensive computations
  ...
  // now update the UI. We don't depend on the result,
  // so use async.
  display.asyncExec (new Runnable () {
     public void run () { 
        if (myWindow.isDisposed())  // check if
still around 
          return;
        myWindow.redraw ();
     }
  });
  // now do more computations


In some products, I've noticed .log files littered with exceptions because
the asyncExec is processed after the window has already closed.  It
wouldn't be a bad idea to integrate this check into the SWT API, e.g.:

    myWindow.asyncUpdate(new Runnable...);

This in turn would check if the widget still exists before executing the
runnable. 

-- Dan 



----- Message from "Hélène ORTIZ" <hchagnot@xxxxxxxxxxxxxxx>
on Thu, 21 Oct 2004 10:37:02 +0200 (CEST) -----

To:	<platform-swt-dev@xxxxxxxxxxx>
Subject:	Re: [platform-swt-dev] in a sub thread, how to call a widget of its father

Tina,

For a code sample, have a look here :

http://help.eclipse.org/help30/index.jsp?topic=/org.eclipse.platform.doc.isv/guide/swt_threading.htm

> Hi
>   So, may I use event and listener to inform the UI Thread to
modify
> its widget such as Label.
>   If it can, could you please provide a slip of code !
> Regard
> -Tina
>