iOS: strange flash when setting acceleratedRendering to false

[J. Landman Gay]

On 2/7/12 4:42 PM, Chris Sheffield wrote:
>
> I have a card that contains a field object with words set up as
> links. When a link is clicked, a "pop-up" group is displayed that
> includes a blended button that covers the background in order to
> disallow interacting with anything else until the "pop-up" is
> dismissed. When this pop-up is displayed, I'm setting
> acceleratedRendering to false. If I don't then the blended button
> does not display properly (maybe this is a bug that needs to be
> fixed?). However, setting acceleratedRendering to false is causing
> this strange flash on the screen. And it doesn't matter if I do it
> while the screen is locked or not. Setting acceleratedRendering back
> to true does not cause the flash. The issue occurs both in the
> simulator and on the device.

I don't have the answer, but you might try setting the compositorType to 
empty and back, instead of turning off rendering entirely. The docs make 
an oblique reference to that and it's working in my app. The difference 
is, I set it between card changes instead of between object changes, so 
who knows, but it's probably worth a try.

Another thing might depend on how your button is blended. Accelerated 
rendering doesn't allow for very many ink types. The release notes 
mention that "Only 'blendSrcOver' and the image processing blend inks 
will work". If changing the ink works, you wouldn't have to adjust the 
rendering at all.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com