[Bug] Content inside Flexlayout not being rendered when wrap="reverse"

[feokuma]

Description

Trying to create a kind of toast of android, I used a Flexlayout inside the Stacklayout to control the height of the content. Using Wrap="Wrap" or Wrap="NoWrap" works but, when config with Wrap="Reverse" then content isn't renderer. Removing the Stacklayout then content is rendered but the height is automatically set to whole screen.

Maybe this issue might be related to https://github.com/xamarin/Xamarin.Forms/issues/9537

Steps to Reproduce

1. Create a screen with the following code

   <Frame Padding="10"
          CornerRadius="10"
          Margin="10"
          BackgroundColor="Gray"
          VerticalOptions="End"
          HorizontalOptions="Center"
          HasShadow="False">
       <StackLayout >
           <FlexLayout Direction="Row"
                       Wrap="Wrap"
                       JustifyContent="SpaceBetween">
               <Label Text="Teste Label"
                      TextColor="Green"
                      BackgroundColor="LightGreen"/>
               <Label x:Name="xamarin"
                      Margin="0,5"
                      Text="Welcome to Xamarin.Forms!!!!!!"
                      TextColor="Blue"
                      BackgroundColor="LightBlue"
                      HorizontalOptions="EndAndExpand"
                      VerticalOptions="CenterAndExpand" />
           </FlexLayout>
       </StackLayout>
   </Frame>

2. Change the property Wrap to Reverse

    <Frame Padding="10"
           CornerRadius="10"
           Margin="10"
           BackgroundColor="Gray"
           VerticalOptions="End"
           HorizontalOptions="Center"
           HasShadow="False">
        <StackLayout >
            <FlexLayout Direction="Row"
                        Wrap="Reverse"
                        JustifyContent="SpaceBetween">
                <Label Text="Teste Label"
                       TextColor="Green"
                       BackgroundColor="LightGreen"/>
                <Label x:Name="xamarin"
                       Margin="0,5"
                       Text="Welcome to Xamarin.Forms!!!!!!"
                       TextColor="Blue"
                       BackgroundColor="LightBlue"
                       HorizontalOptions="EndAndExpand"
                       VerticalOptions="CenterAndExpand" />
            </FlexLayout>
        </StackLayout>
    </Frame>

Expected Behavior

When set Wrap="Reverse" then blue text must be on the top

Actual Behavior

Screen using flexlayout with Wrap="Reverse" inside Stacklayout

Screen using flexlayout with Wrap="Reverse" without Stacklayout

Basic Information

• Version with issue: 4.1 to 4.6
• IDE: Visual Studio for Mac
• Platform Target Frameworks:
  • iOS: 13.3
  • Android: 9.0
• Android Support Library Version: 28.0.0.1
• Xamarin: 4.6.0.800

Reproduction Link

https://github.com/feokuma/FlexlayoutTest

Workaround

[Xyotic]

Happens to me as well..