<AbsoluteLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" >

        <StackLayout VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand"  AbsoluteLayout.LayoutFlags="All"
                     AbsoluteLayout.LayoutBounds="0,0,1,1">
            <ScrollView VerticalOptions="FillAndExpand">
                <StackLayout VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" x:Name="webViewLayout">
                    <WebView x:Name="webcontentcontrol" Source="{Binding WebViewSource}" VerticalOptions="FillAndExpand" HorizontalOptions="Fill"></WebView>
                </StackLayout>
            </ScrollView>
        </StackLayout>

        <StackLayout IsVisible="{Binding IsBusy}"
             AbsoluteLayout.LayoutFlags="PositionProportional"
             AbsoluteLayout.LayoutBounds="0.5,0.5,-1,-1">

            <ActivityIndicator IsRunning="{Binding IsBusy}" Style="{StaticResource ActivityIndicatorStyle}"/>

            <Label Text="Loading..." IsVisible="{Binding IsBusy}"  HorizontalOptions="Center" Style="{StaticResource ActivityIndicatorLabelStyle}"/>

        </StackLayout>
    </AbsoluteLayout>

public AnnouncementPage()
    {
        InitializeComponent();
        BindWebViewControl();
    }

    protected override void OnAppearing()
    {
        webViewLayout.IsVisible = false;
        IsBusy= true;
    }
    private async void BindWebViewControl()
    {
        var result = await _dataService.GetAnnouncement();
        webcontentcontrol.Source = result.Data.First().WebViewSource;
        IsBusy = false;
        webViewLayout.IsVisible = true;
    }