Alternate background color in Listview XAML

I'm using a listView based on itemTemplate. So i need in my template to alternate the background color :
- fist row: white
- second row:gray
- third row: white
- forth: gray

this is my template:

     <DataTemplate x:Key="ItemFlight" >
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="60"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>
            <Border Background="#28AADB" Margin="2">
                <Image Source="{Binding Path=IsArrival, Converter={StaticResource BooleanToImageDisplayConverter}}" Width="30" Height="30" VerticalAlignment="Center" Margin="5"/>
            </Border>
            <Grid Grid.Column="1" VerticalAlignment="Center">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="4*"/>
                    <ColumnDefinition Width="3*"/>
                    <ColumnDefinition Width="3*"/>
                    <ColumnDefinition Width="6*"/>
                </Grid.ColumnDefinitions>
                <Grid.RowDefinitions>
                    <RowDefinition Height="*"/>
                    <RowDefinition Height="*"/>
                </Grid.RowDefinitions>

                <TextBlock Text="{Binding FlightName}" FontWeight="Bold" Grid.Column="0" Grid.Row="0"  Margin="10" Style="{StaticResource MyTextBlockStyle}"/>

                <TextBlock Text="{Binding ArrivalOrDepartDateTime, Converter={StaticResource DateTimeConverter}}"  FontWeight="Bold" Grid.Column="0" Grid.Row="1" Margin="10" Style="{StaticResource MyTextBlockStyle}"/>

                <TextBlock Text="{Binding Terminal, Converter={StaticResource StringUpperConverter}}" Grid.Column="1" Grid.Row="0" Margin="10"  Visibility="{Binding Path=IsArrival,Converter={StaticResource BooleanToVisibilityReverseConverter}}