How to display the expander icon in the header at collapsed state and content at expand state in Xamarin.Forms Expander (SfExpander)?

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:ExpanderXamarin"
             xmlns:syncfusion="clr-namespace:Syncfusion.XForms.Expander;assembly=Syncfusion.Expander.XForms"
             x:Class="ExpanderXamarin.MainPage" Padding="{OnPlatform iOS='0,40,0,0'}">
    <ContentPage.Resources>
        <ResourceDictionary>
            <OnPlatform x:TypeArguments="x:String" x:Key="ExpanderIcon">
                <On Platform="Android" Value="ExpanderIcons.ttf#ExpanderIcons" />
                <On Platform="UWP" Value="/Assets/ExpanderIcons.ttf#ExpanderIcons" />
                <On Platform="iOS" Value="ExpanderIcons" />
            </OnPlatform>
        </ResourceDictionary>
        <local:ExpanderIconConverter x:Key="ExpanderIconConverter"/>
        <local:ExpanderVisibilityConverter x:Key="ExpanderVisibilityConverter"/>
    </ContentPage.Resources>
    <ContentPage.Content>
        <ScrollView BackgroundColor="#EDF2F5" Margin="{OnPlatform iOS='0,40,0,0'}">
            <StackLayout>
                <syncfusion:SfExpander x:Name="expander1" HeaderIconPosition="None">
                    <syncfusion:SfExpander.Header>
                        <Grid HeightRequest="50">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="50"/>
                                <ColumnDefinition Width="*"/>
                            </Grid.ColumnDefinitions>
                            <Label HorizontalOptions="Center" VerticalOptions="Center"
                                FontFamily="{StaticResource ExpanderIcon}"
                                IsVisible="{Binding Path=IsExpanded, Source={x:Reference expander1}, Converter={StaticResource ExpanderVisibilityConverter}, ConverterParameter=Header}" 
                                Text="{Binding Path=IsExpanded,Source={x:Reference expander1}, Converter={StaticResource ExpanderIconConverter}, ConverterParameter={x:Static Device.RuntimePlatform}}"/>
                            <Label Text="Veg Pizza" Grid.Column="1" TextColor="#495F6E"  VerticalTextAlignment="Center" />
                        </Grid>
                    </syncfusion:SfExpander.Header>
                    <syncfusion:SfExpander.Content>
                        <Grid BackgroundColor="#FFFFFF">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="50"/>
                                <ColumnDefinition Width="*"/>
                            </Grid.ColumnDefinitions>
                            <Label HorizontalOptions="Center" VerticalOptions="Center"
                                   FontFamily="{StaticResource ExpanderIcon}" 
                                   IsVisible="{Binding Path=IsExpanded,Source={x:Reference expander1}, Converter={StaticResource ExpanderVisibilityConverter}, ConverterParameter=Content}" 
                                   Text="{Binding Path=IsExpanded,Source={x:Reference expander1}, Converter={StaticResource ExpanderIconConverter}, ConverterParameter={x:Static Device.RuntimePlatform}}"/>
                            <Label BackgroundColor="#FFFFFF" HeightRequest="50" Grid.Column="1" Text="Veg pizza is prepared with the items that meet vegetarian standards by not including any meat or animal tissue products." TextColor="#303030" VerticalTextAlignment="Center"/>
                        </Grid>
                    </syncfusion:SfExpander.Content>
                </syncfusion:SfExpander>
            </StackLayout>
        </ScrollView>
    </ContentPage.Content>
</ContentPage>

public class ExpanderVisibilityConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if ((string)parameter == "Header")
            return (bool)value ? false : true;
        else
            return (bool)value ? true : false;
    }
 
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}