Xamarin Stacklayout VerticalOptions CenterAndExpand not working - xamarin

Question

Hi Guys probably very easy question for Xamarin expert I am trying to vertically center align stacklayout control and it is working fine in android mobile but not working in windows mobile device. My code is below
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="aa.Views.MainPage">
<ScrollView>
<StackLayout Orientation="Vertical" VerticalOptions="CenterAndExpand"
Padding="20" Spacing="10">
<Entry x:Name="enEmail" Placeholder="Email"></Entry>
<Entry x:Name="enPassword" IsPassword="True" Placeholder="Password"></Entry>
<Button Text="Login" Clicked="OnClicked_btnLogin" x:Name="btnLogin"></Button>
<Button Text="Register" Clicked="OnClicked_btnRegister" x:Name="btnRegister"></Button>
</StackLayout>
</ScrollView>
</ContentPage>
For more details please have a look at the attached images and help me how would i align it in center of screen for windows phone

Answer 1

its StackLayout: puts views consecutive one another. If you want to move buttons to down side use Grid instead like:
<Grid RowSpacing="10"><!--RowSpacing gives some space between rows-->
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/> <!--You can also use constant size also-->
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/> <!--This fill the empty space-->
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Entry Grid.Row="0" Placeholder=" Email"/>
<Entry Grid.Row="1" Placeholder=" Password" IsPassword="True"/>
<Button Grid.Row="3" Text="Login" />
<Button Grid.Row="4" Text="Register" />
</Grid>

Answer 2

Try the code below, it will give you a scroll view plus your fields will be aligned to the center
<ScrollView>
<AbsoluteLayout>
<StackLayout Orientation="Vertical" AbsoluteLayout.LayoutBounds="0, 0, 1, 1" AbsoluteLayout.LayoutFlags="All" x:Name="maincontent" Spacing="0">
<StackLayout Orientation="Vertical" VerticalOptions="CenterAndExpand"
Padding="20" Spacing="10">
<Entry x:Name="enEmail" Placeholder="Email"></Entry>
<Entry x:Name="enPassword" IsPassword="True" Placeholder="Password"></Entry>
<Button Text="Login" Clicked="OnClicked_btnLogin" x:Name="btnLogin"></Button>
<Button Text="Register" Clicked="OnClicked_btnRegister" x:Name="btnRegister"></Button>
</StackLayout>
</StackLayout>
</AbsoluteLayout>
</ScrollView>