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Re: Measuring colours accurately in mobile apps

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From: Joe Humbert (A11y)
Date: Jun 23, 2021 5:58AM

Accessibility Inspector that comes with Xcode on MacOS will allow you to get accurate colors if they fail certain criteria. You can use this with any Application (your own developed, client source code, or Apps from the app store). You will need to connect you iOS/iPadOS device to a Mac with Xcode installed. I think you need to register the device with Xcode, but then it will work.

https://developer.apple.com/videos/play/wwdc2019/257/

I can probably do a screen recording tomorrow and send a link.

For Android, Accessibility Scanner will get you the colors, but not the font sizes or weights. I don't remember off the top of my head if Accessibility Inspector's Audit gives the font size/ weight.

Thankx,
Joe Humbert, CPWA
Accessibility Champion
Android & iOS Accessibility Novice
Twitter: @joehumbert

-----Original Message-----
From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of Steve Green
Sent: Wednesday, June 23, 2021 3:22 AM
To: WebAIM Discussion List < <EMAIL REMOVED> >
Subject: Re: [WebAIM] Measuring colours accurately in mobile apps

Thanks, it's good to know we're not missing anything obvious.

Steve

-----Original Message-----
From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of Patrick H. Lauke
Sent: 23 June 2021 08:03
To: <EMAIL REMOVED>
Subject: Re: [WebAIM] Measuring colours accurately in mobile apps

We generally go down the "take a screenshot on device, then transfer it to a desktop/laptop device for traditional testing with CCA or similar"
path, despite its potential flaws (for instance, even taking an on-device screenshot can lead to specific colour profiles/adaptations on the device being applied, making the colour drift slightly). And you're exactly right, other methods like Zoom, Reflector, or similar will compress the video leading to changes in colour, and should always be avoided.

When emailing, if given the option, go for "original" rather than any email client resizing. That should guarantee that it takes the raw screenshot that was saved, without any further recompression.

There's no (legal/legit) way to grab an app from the app store/google play store and then decompiling it (especially since these apps are digitially signed etc when packaged).

When reporting on colour contrast failures (and luckily, we only do failures, and don't list all colour combos including passes) we also include wording that explains the values are approximate, based on having to test what was available to us. If a client wants more precision/certainty, we ask for actual accurate colour values they used, or request that they give us access to a development build/XCode project/similar to open in an actual development tool.

P
--
Patrick H. Lauke

https://www.splintered.co.uk/ | https://github.com/patrickhlauke https://flickr.com/photos/redux/ | https://www.deviantart.com/redux
twitter: @patrick_h_lauke | skype: patrick_h_lauke