UI changes slowly

Question

Hi

We are using the Embedded Wizard 8.20. In the main loop, it does not call CoreRoot__DoesNeedUpdate(). And we modified the main loop to call it just like 8.30. But it cause a UI touch response slow. This UI draws the touch trace on the screen. We can see the displayed touch trace lags behind the finger when draw the touch trace first time. But the second trace is no problem. I found when UI changes, from one interface to another screen, the Update( viewport, rootObject ) excutes 163- 270 ms, this caused the first touch delay. So what is the problem?

 

        /* refresh the screen, if something has changed and draw its content */
        if ( devices || timers || signals || events )
        {
            if (CoreRoot__DoesNeedUpdate(rootObject))
            {
                Update( viewport, rootObject );
            }

            /* after each processed message start the garbage collection */
            EwReclaimMemory();

            /* print current memory statistic to serial interface - uncomment if needed */
            //EwPrintProfilerStatistic( 0 );
        }

Answer 1

Hi Sully,

as already mentioned in the answer of this question, the execution time is not caused by the function Update() itself - it is caused by the content that has to be displayed within the function Update().

Can you please let us know more details about your dedicated application?

If your screens are containing a lot of graphical objects (e.g. with complex operations like warp or scale that is not hardware accelerated on your platform) the redrawing of the entire screen may take a certain time.

If your screens are accessing your device drivers in order to query data, the response time of the UI and the redrawing of the screens may be delayed by the underlying system.

Without knowing the details, I can just give you some rough ideas.

Is it possible to reduce the problem to a reproducieble example? Then it will be easier to support you.

Best regards,

Manfred.