Full screen flicker when displaying progress overlay

[jdmunro]

Using 0.5.0.

Steps to reproduce:

Display a progress overlay on device using the sample app. This is reproducible on iPhone and iPad, although it is usually more noticeable on iPad. The screen will briefly flicker with a buggy texture.

I think from your previous comments that this is related to the asynchronous blur texture rendering. This is likely related to #42

See video here: https://docs.google.com/file/d/0B7hk_IdN2v-QRy1lNWZHTmg1SDNQWHotalRrVjFldHlhd0lR/edit

[mrackwitz]

Thank you again for your bug report. I would need to further investigate this issue to fix this flickering.

One good thing: with iOS 8 there will be UIBlurEffect in combination with UIVisualEffectView, so at least then this can be solved in a more elegant way.

[jdmunro]

Thanks! In the meantime I have disabled the blur texture generation, it is a compromise but the difference is not too noticeable unless you know what to look for.

[mrackwitz]

See #51 for a look-out.

[jeffreyjackson]

I can confirm this as well. No changes in source code from iOS7 to iOS8. When overlay is displayed I see a slight full screen glitch.

[tadadev]

Another confirmation as above from iOS7 to iOS8

[jeffreyjackson]

Hey @tadadev, just curious are you displaying overlayview on top of a scrollview or tableview?

[tadadev]

Base iOS SDK 8.0, Deployment Target 7.0 Using a Progress Overlay on top of a normal view... Also downloaded the sample project, and it glitches/flickers there as well on all the Progress Overlay Views.

[tadadev]

Anybody have any ideas on how to solve? Works fine on iOS7, but a killer on iOS8. May have to look into something else.

[jeffreyjackson]

If there isn't a solution within the next few days I may try to work on a pull request. I am not aware of any other activity views that are as nice as this. I'll be very excited about this progress view when we are able to change the background tint as well.

On Wednesday, October 1, 2014, tadadev notifications@github.com wrote:

Anybody have any ideas on how to solve? Works fine on iOS7, but a killer on iOS8. May have to look into something else.

— Reply to this email directly or view it on GitHub https://github.com/mrackwitz/MRProgress/issues/46#issuecomment-57540414.

[mrackwitz]

I think, those are two different issues, which are related. There is definitively a regression in iOS 8. I still need to put together a minimum Example project to file a radar for this issue. If you find any workarounds a PR is welcome.

@tadadev: One workaround would be to subclass the progress view and overwrite its createBlurView method. You can use there for example the layer of the navigation bar to use the default system effect. (_UIBackdropView) But I can't guarantee that this is AppStore-compliant.

[tadadev]

@jeffreyjackson Yes this is def the nicest I've seen and I thank the devs.

@mrackwitz I was actually poking around in this, and decided to override that method. My project was built for iOS7 and uses none of the new features of iOS8 as of yet. Since we're on the verge of going to Production, we'll use a more general effect for now to bypass the glitching in iOS8 and revisit it later when adding iOS8 features. Thanks!

[mrackwitz]

I've pushed a version yesterday which should finally solve the most of the blur issues and distanced from using Apple's UIVisualEffectView and it's faulty blur implementation as it caused such a lot of issues. I've currently no older device at hand, so if anyone of you could give me some feedback of the current HEAD (pod 'MRProgress', :head), I would appreciate your feedback as this new upcoming version will definitively need more resources.

[jpaas]

I just tried master and I haven't seen any issues yet. Thanks!

[mrackwitz]

Thanks for letting me know!