How to Display Loading Message in Xamarin.Forms

I am new to Xamarin.Forms in which i need loading message how i can display the loading message please help me out

Code:-

   <AbsoluteLayout>
       <StackLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" AbsoluteLayout.LayoutBounds="0, 0, 1, 1"
             AbsoluteLayout.LayoutFlags="All" Padding="30" >
       <Grid>
            //something
       </Grid>
       </StackLayout>
       <ContentView x:Name="overlay" AbsoluteLayout.LayoutBounds="0, 0, 1, 1"  AbsoluteLayout.LayoutFlags="All" IsVisible="False" BackgroundColor="#C0808080" Padding="10, 0">
       <ActivityIndicator  WidthRequest="110" HeightRequest="70" IsRunning="True" IsVisible="True" Color="Black" HorizontalOptions="CenterAndExpand" VerticalOptions="CenterAndExpand"/>
       </ContentView>
    </AbsoluteLayout>

Thanx In Advance

Cheers