How do you get a box to fully expand to its container's width without WidthRequest="9999999"?

Question

I have tried HorizontalOptions="Fill/FillAndExpand/CenterAndExpand", and the grid that this VerticalStackLayout box sits in has a * or Auto size. No options seem to work exception WidthRequest="999999". Then it automatically sizes to its container's content width. Its container is a Grid inside of a Border box.

Answer 1

Setting the fill option should work. I suspect that the parent is itself configured to take up enough space to contain its children. As such you are telling a control to be as big as its parent and the parent to be large enough to fit the children. But I'm just guessing based upon the layout. Setting an absolute width of course would solve this issue since the child is now a fixed width and the parent resizes accordingly.

Please provide the XAML that replicates the problem. If you have any custom code that is changing the widths of any of the controls then that would be useful as well.

Answer 2

@Michael Taylor

<CollectionView.ItemTemplate>  
    <DataTemplate x:DataType="model:Device">  
        <Grid Padding="10" HorizontalOptions="Center">  
            <Border HorizontalOptions="CenterAndExpand" HeightRequest="140" Style="{StaticResource CardView}"  
                    StrokeShape="RoundRectangle 16">  
                <Border.GestureRecognizers>  
                    <TapGestureRecognizer x:Name="avatarTapGesture"  
                        Command="{Binding Source={RelativeSource AncestorType={x:Type viewmodel:DeviceListViewModel}}, Path=GoToDetailsCommand}"  
                        CommandParameter="{Binding .}"/>  
                </Border.GestureRecognizers>  
                <Grid Padding="0" ColumnDefinitions="128,Auto">  
                    <Border Style="{StaticResource CardView}"  
                            Stroke="{Binding ., Converter={StaticResource deviceToStatusColor}}"  
                            BackgroundColor="{Binding ., Converter={StaticResource deviceToStatusColor}}"  
                            StrokeShape="RoundRectangle 64"  
                            StrokeThickness="7"  
                            WidthRequest="128"  
                            HeightRequest="128"  
                            HorizontalOptions="Center"  
                            VerticalOptions="Center"  
                            Grid.Column="0">  
                        <Image  
                            Aspect="AspectFill"  
                            Source="{Binding Image}" />  
                    </Border>  
                    <VerticalStackLayout  
                        HorizontalOptions="Center"  
                        VerticalOptions="Center"  
                        WidthRequest="9999999"  
                        Grid.Column="1"  
                        Padding="10">  
                        <Label Style="{StaticResource LargeLabel}" Text="{Binding Name}" />  
                    </VerticalStackLayout>  
                </Grid>  
            </Border>  
        </Grid>  
    </DataTemplate>  
</CollectionView.ItemTemplate>