Using OnIdiom with AbsoluteLayout - xaml

Question

I have circular buttons and am trying to change the size of them depending on if they are on phone or tablet using AbsolutLayout.
Here is my xaml:
<Frame BackgroundColor="{StaticResource ThemeColor}" Padding="0" CornerRadius="40" AbsoluteLayout.LayoutBounds="{StaticResource HomeCircle}" AbsoluteLayout.LayoutFlags="PositionProportional">
<Label Text="" HorizontalOptions="Center" VerticalOptions="Center" Style="{StaticResource Icon}" TextColor="{StaticResource LabelColor}"/>
<Frame.GestureRecognizers>
<TapGestureRecognizer Tapped="Directions"/>
</Frame.GestureRecognizers>
</Frame>
<AbsoluteLayout.Resources>
<ResourceDictionary>
<OnIdiom x:Key="HomeCircle" x:TypeArguments="Frame" Phone=".85,.375, 80, 80"
Tablet=".85,.375, 120, 120"/>
</ResourceDictionary>
</AbsoluteLayout.Resources>
I looked at this resource and it did not work:
How to use attached properties such as Grid.Row, AbsoluteLayout.LayoutFlags to OnPlatform tag in Xamarin Forms
Edit: Have tried TypeArguments of Rectangle, AbsoluteLayout, and Frame and they all give this error:
Error XFC0009 No property, BindableProperty, or event found for "Phone", or mismatching type between value and property.
Edit: Have also looked at this thread and it provides the same error:
https://xamarin.github.io/bugzilla-archives/55/55183/bug.html

Answer 1

I faced the same problem in the past. My solution is to set the AbsoluteLayout bounds by Binding in place of StaticResource.
In the ViewModel:
public Xamarin.Forms.Rectangle HomeCircle => Xamarin.Forms.Device.Idiom == TargetIdiom.Phone ? new Xamarin.Forms.Rectangle(0.5f, 0.5f, 80, 80) : new Xamarin.Forms.Rectangle(0.5f, 0.5f, 120, 120);
In the yaml:
<AbsoluteLayout>
<Frame BackgroundColor="Gray"
Padding="0"
CornerRadius="40"
AbsoluteLayout.LayoutBounds="{Binding HomeCircle}"
AbsoluteLayout.LayoutFlags="PositionProportional">
<Label Text="TEST"
HorizontalOptions="Center"
VerticalOptions="Center"
TextColor="Black"/>
<Frame.GestureRecognizers>
<TapGestureRecognizer Command="{Binding DoSomething}"/>
</Frame.GestureRecognizers>
</Frame>
</AbsoluteLayout>
Anyway AbsoluteLayout.LayoutBounds requires Rectangle, and markup doesn't always allow everything :)