Bug 38055 - There is no way to define a style with a custom font size that obeys accessibility settings
Summary: There is no way to define a style with a custom font size that obeys accessib...
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 2.0.0
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2016-01-26 15:06 UTC by John Miller [MSFT]
Modified: 2016-12-20 21:17 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

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Description John Miller [MSFT] 2016-01-26 15:06:04 UTC

   There is a requirement to be able to define a Style with a FontSize that will obey accessibility changes on iOS (presumably, whatever the equivalent on Android is also). 

   The current support that is close to this (basing a style on an existing dynamic style) does not let you specify/change the default FontSize for that style and therefore does not fulfill this requirement. 

**Steps to Reproduce:**

   <Style x:Key="CustomStyle" TargetType="Label" BaseResourceKey="SubtitleStyle">
	<Setter Property="Label.FontSize" Value="8"/>
	<Setter Property="Label.TextColor" Value="Color.Pink"/>

**Actual Results:**

   The FontSize always stays at 8, regardless of accessibility changes. 

**Expected Results:**

   FontSize should start at 8 when on "default" accessibility and then obey any changes.

**Build Date & Platform:**

   XF 2.0
Comment 1 John Miller [MSFT] 2016-01-26 16:23:39 UTC
I misunderstood how this worked on iOS. I did not realize that the font sizes being used are inherited from the OS, using UIFont.Preferred*. Changing the FontSize in a Style would already override that. 

On iOS, to manually handle font size changes when accessibility changes, you can listen for the "UIContentSizeCategoryDidChangeNotification" which is fired when accessibility changes. This might also be required if using a non-system font (custom fonts). This is probably not a bug and it's already implemented as the OS supports - someone from the Forms team, please confirm.
Comment 2 Jason Smith [MSFT] 2016-12-20 21:17:37 UTC
Correct this is not a bug, cheers :)