NewLC - Refreshing/Flushing screen to display several bitmaps ... - Comments

Re: Refreshing/Flushing screen to display several bitmaps ...

laurents — Wed, 03 Dec 2008 11:54:19 +0100

Thank you for your advices alh,

I removed all my activate/deactivate and all User::After.

In my HandleCommandL to handle menu events, I removed my ShowSplashScreen() and Show2ndScren(), I let my SetScreenType function and I added the DrawNow() function at the end: It works, I can change my background as I wanted!

Thx

Re: Refreshing/Flushing screen to display several bitmaps ...

alh — Wed, 03 Dec 2008 09:44:56 +0100

Your problem with you never seeing the first bitmap could just be because of how the epoc emulator starts up when you start it up from carbide.

Your app actually starts far before the UI is fully initialized, so it probably has time to go to the second image before you get to see it.
Try start epoc from a command prompt, and then just navigate to and start the app like you would on a phone, and you might see your first splash too.

Re: Refreshing/Flushing screen to display several bitmaps ...

alh — Wed, 03 Dec 2008 09:41:38 +0100

as long as your function is called from within a draw function, you should neither call activate, nor deactivate.
I notice you have a lone gc.Deactivate() in your "ShowSplashScreen".

Remove them all...

Also, you should absolutely not call User::After from within a draw function, that can make the view framework timeout and give you a ViewSrv::11 panic.
Draw functions must always return as quickly as possible.

You should let a timer handle the delay, let it change the image to show and call DrawNow after a second.
CPeriodic and a static callback should be convenient for this.

Re: Refreshing/Flushing screen to display several bitmaps ...

laurents — Tue, 02 Dec 2008 18:04:58 +0100

I updated my source code :

at begining iScreenType = 0;

void CGraphicsAppView::Draw( const TRect& /*aRect*/ ) const
    {  
    switch( iScreenType )
        {
        case 1 :
            Show2ndDisplay();
            break;
        case 0 :
        default:
            ShowSplashDisplay();
            break;
        }
    }

When I let the pair gc.Activate( *DrawableWindow() ); and gc.Deactivate(); I get a WSERV 10 panic :
"Attempted to activate an already active graphics context. ".
When I start the application the splash screen is displayed then when I click in my menu item corresponding to the Show2ndDisplay() I set the iScreenType variable and the panic is raised.

When i remove the pair Activate/Deactivate I get a WSERV 9 panic :
"A drawing request was sent to a graphics context when the context was not active. "

I don't understand :/
Can somebody please tell me where am I going wrong.
Thanks.

Refreshing/Flushing screen to display several bitmaps ...

laurents — Tue, 02 Dec 2008 15:40:39 +0100

Hi,

I created several functions to display a picture for a given time :

ShowSplashDisplay : to display a splash screen picture
Show2ndDisplay : to display an other picture during my program execution

I don't succeed to display two pictures in the same program execution.