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Re: Safari Pinch Zoom for 1.4.4


From: glen walker
Date: Oct 27, 2020 9:42AM

I agree with Patrick with regards to testing 1.4.4 separately from 1.4.11
but I don't use pinch/zoom to test 1.4.4. To me, that's not really
resizing the text since it magnifies the entire viewport. Nothing will get
cut off or overlap if the viewport changes so it's kind of useless to prove
1.4.4 passes. I use it all the time, personally, but not in my testing.

I have a bookmarklet on iOS that actually does increase the text size but I
don't really use that for testing either unless I find the website has
trouble with 1.4.4 on the desktop. Then I might use the bookmarklet out of
curiosity to see if it has a problem on iOS too.

It's not perfect and only changes elements that have a fontSize property so
things like images don't change (kind of like the zoom text size only
feature in browsers).

Here's the exact code that you can copy/paste to a bookmarklet. I use '+'
and '-' as the names of my bookmarklets.



The only difference between the two is "s+=2" vs "s-=2".

Here's the '+' bookmarklet again but urldecoded and pretty printed (yes,
there are superfluous '{'):

var p=document.getElementsByTagName('*');
var s=parseInt(p[i].style.fontSize.replace("px",""));
var s=12;

Pretty basic. Get all the elements on the page. If it has a fontsize, use
it. If it doesn't, default to 12. Increase or decrease the font size by
2. Set the font size back on the element.

For *native* iOS app testing, I use the "Text Size" feature in settings.
Some might consider the "Text Size" feature an assistive technology and
thus not be applicable to 1.4.4 since it says "without assistive
technology" but I'll leave that up to you to decide. I think it's great if
an app honors the Text Size setting but if it doesn't, it's questionable
whether that technically fails 1.4.4. But if you want to use it, you have
to enable the "Larger Accessibility Sizes" (which seems to hint that it's
assistive technology) and then move the slider so that it's four ticks from
the right end. That gives you a fontsize that is just below 200% from the
original, but it's close enough to play with 1.4.4.

If you want to confirm the sizes of Text Size, see the "typography" section
of Apple's Human Interface Guidelines page from Apple. The "Dynamic Type
Sizes" section (
of that doc shows 7 font sizes (xsmall to xxxlarge) that correspond to the
7 tickmarks on the "larger text" accessibility option.

If you enable "Larger Accessibility Sizes" option in a11y settings, that
adds an additional 5 font sizes (AX1 to AX5) (
or 5 tickmarks to the slider.

If you look at the "Large (Default)" table under "Dynamic Type Sizes", it
says "body" text is 17pts. If we want 200% zoom, that would be 34pt. If
you look in the second table, under AX2, "body" size is 33 pt. Not quite
34pt but close enough. AX2 is 4 tickmarks from the right end of the
AX1-AX5 line, corresponding to 4 tickmarks from the right end of the text
slider, which is what I use for 200% zoom.

Probably way more than you wanted to know and definitely way more than I
intended to type.

On Tue, Oct 27, 2020 at 8:15 AM Patrick H. Lauke < <EMAIL REMOVED> >

> On 27/10/2020 14:01, Justin Leasure wrote:
> > Hello,
> >
> > I sent a similar question out about a week ago, but I had a follow up.
> Does
> > "pinch zoom" within Safari Mobile meet the requirements of 1.4.4 (resize
> > text)? The requirement states that zooming must not cause "loss of
> content
> > or functionality." Pinch zooming causes full viewport zooming and can
> cause
> > excessive horizontal/vertical scrolling, which I think we would all agree
> > is not ideal. However, if you had a situation where the browser zoom
> (using
> > the "Aa" zoom feature within Safari) feature caused a loss of
> > functionality, would you make the argument that a website still meets
> 1.4.4
> > if pinch zoom is enabled? I know that 1.4.11 speaks to the fact that
> reflow
> > of content (which should only require one dimensional scrolling) is not
> > often achievable on mobile devices. So, one could take this to mean that
> > 1.4.4 is still achieved even with two dimensional scrolling. Thanks in
> > advance for your input.
> 1.4.4 and 1.4.11 need to be evaluated separately.
> 1.4.4 does not disallow bi-directional scrolling from occurring. All it
> requires is that users be able somehow (not specified how) resize to
> 200% without things breaking (controls or content overlapping, being cut
> off and unusuable/unreadable, etc). So yes, pinch-zoom is an acceptable
> mechanism to pass 1.4.4 if nothing gets cut off/overlapped. Same way
> that zooming on desktop, even without reflowing (e.g. if the page has
> explicitly-sized containers or elements, and is not doing anything
> responsive or elastic), is also a valid way of passing 1.4.4 if nothing
> gets overlapped/cut off.
> 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
> > > > >