"Markus Ewald" <Markus_Ewald@gmx.net> wrote in message
news:uosmcbKhGHA.1264@TK2MSFTNGP05.phx.gbl...
> I created a simple splash screen with a progress bar in it that should
> keep the user entertained while my application is busy loading resources.
>
> The code goes like this:
>
> // Display the loading splash screen while we're busy.
> using(StartupForm loadingScreen = new StartupForm()) {
> loadingScreen.Show();
>
> loadResourcesThread.Start();
> loadResourcesThread.Join();
>
> loadingScreen.Close();
> }
>
> What I expected was that the loading screen would still be kept
> responsive (MSDN on Thread.Join(): "Blocks the calling thread until a
> thread terminates, while continuing to perform standard COM and
> SendMessage pumping"). What happens instead is that the splash screen
> uses the hourglass cursor and doesn't redraw its controls while the main
> thread sits in loadResourceThread.Join().
>
> It works as expected if I use an ugly hack like this:
>
> loadResourcesThread.Start();
> while(loadResourcesThread.IsAlive)
> Application.DoEvents();
> loadResourcesThread.Join();
>
> So is executing the message pump not enough to keep the UI in a .NET
> application responsive?
>
> Thanks ahead,
> -Markus-
>

Michael D. Ober wrote:
>
> If the thread you are blocking with the Thread.Join() is the main
> application thread, the message pump cannot be processed. COM and
> SendMessage are still working - it's simply that the receiving thread is
> blocked.
>
> Mike Ober.
>
> "Markus Ewald" <Markus_Ewald@gmx.net> wrote in message
> news:uosmcbKhGHA.1264@TK2MSFTNGP05.phx.gbl...
>> I created a simple splash screen with a progress bar in it that should
>> keep the user entertained while my application is busy loading resources.
>>
>> The code goes like this:
>>
>> // Display the loading splash screen while we're busy.
>> using(StartupForm loadingScreen = new StartupForm()) {
>> loadingScreen.Show();
>>
>> loadResourcesThread.Start();
>> loadResourcesThread.Join();
>>
>> loadingScreen.Close();
>> }
>>
>> What I expected was that the loading screen would still be kept
>> responsive (MSDN on Thread.Join(): "Blocks the calling thread until a
>> thread terminates, while continuing to perform standard COM and
>> SendMessage pumping"). What happens instead is that the splash screen
>> uses the hourglass cursor and doesn't redraw its controls while the main
>> thread sits in loadResourceThread.Join().
>>
>> It works as expected if I use an ugly hack like this:
>>
>> loadResourcesThread.Start();
>> while(loadResourcesThread.IsAlive)
>> Application.DoEvents();
>> loadResourcesThread.Join();
>>
>> So is executing the message pump not enough to keep the UI in a .NET
>> application responsive?
>>
>> Thanks ahead,
>> -Markus-
>>
>
>