Bug 60757 - XAML OnPlatform not work in .Net Standard 2 project
Summary: XAML OnPlatform not work in .Net Standard 2 project
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 2.5.0
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2017-11-19 10:28 UTC by Khuong Nguyen
Modified: 2017-12-07 14:03 UTC (History)
3 users (show)

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

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Description Khuong Nguyen 2017-11-19 10:28:08 UTC
The simple code like bellow 'cause build (with XamlCompilation) and runtime error: Xamarin.Forms.Xaml.XamlParseException: Position 7:10. Cannot assign property "Margin": Property does not exists, or is not assignable, or mismatching type between value and property

        <OnPlatform x:TypeArguments="x:Double">
            <On Platform="Android"
            <On Platform="iOS"
Comment 1 Paul DiPietro [MSFT] 2017-11-19 14:57:37 UTC

*** This bug has been marked as a duplicate of bug 58922 ***
Comment 2 Khuong Nguyen 2017-11-19 15:24:15 UTC
I think it not like with the #58922 
Here the full sample

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
        <OnPlatform x:TypeArguments="Thickness">
            <On Platform="Android"
            <On Platform="iOS"
	<Label Text="Welcome to Xamarin.Forms!" 
           HorizontalOptions="Center" />

this code work if using PCL or Shared Project but not work on .NETStandard
Comment 3 Jean-Daniel Gasser 2017-12-07 14:03:13 UTC
Exact same problem here. 

This code works on PCL:
  <OnPlatform x:TypeArguments="x:Double">
    <On Platform="iOS" Value="140" />
    <On Platform="Android" Value="140" />
    <On Platform="WinPhone, Windows" Value="180" />

But when I compile the same in a .NET Standard project, then following compilation error appears:
No property, bindable property, or event found for 'WidthRequest', or mismatching type between value and property.