Change the color of the line between the header and the items in a Forms Listview

Hi!

I'm trying to figure out how to change the color of the line between the header and the items in a ListView? Specifically for iOS at the moment, but still in Forms.

XAML and screenshot below.

   <local:ListView ItemsSource="{Binding Sites}" ItemClickCommand="{Binding RowSelected}" 
                    HasUnevenRows="true" SeparatorColor="{StaticResource ListViewSeparatorColor}" SeparatorVisibility="Default">
      <ListView.Header>
        <!-- TODO Translate -->
        <SearchBar x:Name="search" Placeholder="Sök" BackgroundColor="{StaticResource SearchBarBackgroundColor}" />
      </ListView.Header>
      <ListView.ItemTemplate>
        <DataTemplate>
          <ViewCell>
            <ViewCell.View>
              <local:SiteDetailViewCell />
            </ViewCell.View>
          </ViewCell>
        </DataTemplate>
      </ListView.ItemTemplate>
    </local:ListView>