Grid Inside AbsoluteLayout

Hello Guys,

I am using grid inside stacklayout but grid not expand device's full screen.
any solution for this thing.
<ContentPage.Content>


<Grid.RowDefinitions>


</Grid.RowDefinitions>

      <local:CustomEnrty x:Name="entryUserID"
                         Placeholder="User ID"
                         FontSize="Medium"
                         PlaceholderColor="Gray"
                         BackgroundColor="White" />

      <local:CustomEnrty  x:Name="entryPassword"
                          Placeholder="Password"
                          FontSize="Medium"
                          PlaceholderColor="Gray"
                          BackgroundColor="White" />
      <BoxView HeightRequest="15"/>
      <Button Text="Submit"
              Command="{Binding LoginCommand}"
              TextColor="White"
              BackgroundColor="#61386b"/>
    </StackLayout>

  </Grid>
  <ActivityIndicator x:Name="Pageindicator"
                     IsRunning="{Binding IsBusy,Mode=OneWay}"
                     IsVisible="{Binding IsBusy![](https://us.v-cdn.net/5019960/uploads/editor/c8/ay5o1m2utss0.png "")

,Mode=OneWay}"
Color="Red"
AbsoluteLayout.LayoutFlags="All"
AbsoluteLayout.LayoutBounds=".5,.5,.1,.1"
VerticalOptions="Center"
HorizontalOptions="Center" BackgroundColor="Yellow"/>

</AbsoluteLayout>

</ContentPage.Content>

Below i attach image file.