How to add borders Xamarin

Method 1: two layers, inner and outer layers with the background color difference, padding set borders

<StackLayout BackgroundColor="White">
<StackLayout BackgroundColor="Black" Padding="1">
<Editor BackgroundColor="White" />
</StackLayout>
...
</StackLayout>

Method 2: Frame frame can be disposed outside the sleeve may be provided with a rounded edge

1 <Frame Grid.Row="1" MinimumHeightRequest="200" BorderColor="Black" CornerRadius="20" HasShadow="True" BackgroundColor="#cfe2f3">
2 <StackLayout BackgroundColor="Transparent" VerticalOptions="FillAndExpand">
3 <radialView:RadialProgressView VerticalOptions="FillAndExpand" BindingContext="{Binding radialProgressViewModel}" />
4 <Label FontSize="Large" Text="实时数据" TextColor="#3399CC" VerticalOptions="End" HorizontalTextAlignment="Center"></Label>
5 </StackLayout>
6 </Frame>