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UpdateAllViews - OnDraw Lags

DizZzM
DizZzM asked
on
Medium Priority
417 Views
Last Modified: 2013-11-20
Hi Experts,

Developing an application for grabbing data off a bus and displaying it (similiar to Ethereal but for a different protocol). Have the code below in my Doc class. The problem is when I do an updateallviews - my OnDraw() function is putting up a lot of text up on the screen (using a BitMap to avoid flicker) but theres tons of data coming in on the bus and the delay from the time I receive the data to the time it gets drawn on the screen is a few seconds.

Is there an obvious reason why the lag/delay is occuring - is there a simple solution to speed up the time from when I receive data to get it drawn up on the screen?

void MyDoc::OnCommandStop()
{
     stop_recv_flag = 1;
}

void MyDoc::DoEvents()
{  
     MSG msg;  
     while ( ::PeekMessage(&msg, NULL, 0, 0, PM_REMOVE ) )
     {  
          ::TranslateMessage(&msg);
          ::DispatchMessage(&msg);
     }
}

void MyDoc::OnCommandRun()
{
     while(!stop_recv_flag)
     {
          status = read_bus (data);
          if (status == GOTDATA)
          {
               UpdateAllViews(NULL);    
          }  
          DoEvents();              
     }

     stop_recv_flag = 0;
}

Thanks!
Comment
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IT Professional
Top Expert 2005
Commented:
May be you can have a worker thread to receive / read bus data and from your thread function you may send message to your main application to update other views / information to display..

-MAHESH

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