How To Apply A Style To The Listview Item In Xamarin.Forms

    <ContentPage.Resources>
        <ResourceDictionary>
            <Style x:Key="StackStyle" TargetType="StackLayout">
                <Setter Property="BackgroundColor" Value="#4b69a0"/>
            </Style>
            <Style x:Key="LabelStyle" TargetType="Label">
                <Setter Property="TextColor" Value="YellowGreen"/>
                <Setter Property="FontAttributes" Value="Italic" />
            </Style>
        </ResourceDictionary>
    </ContentPage.Resources>
   <Grid>
    <syncfusion:SfListView x:Name="listView" ItemSize="70" 
                        ItemsSource="{Binding contactsinfo}">
        <syncfusion:SfListView.GroupHeaderTemplate>
            <DataTemplate>
                <ViewCell>
                    <ViewCell.View>
                        <StackLayout Style="{StaticResource StackStyle}">
                            <Label Text="{Binding Key}" TextColor="White" />
                        </StackLayout>
                    </ViewCell.View>
                </ViewCell>
            </DataTemplate>
        </syncfusion:SfListView.GroupHeaderTemplate>
        <syncfusion:SfListView.ItemTemplate>
            <DataTemplate>
                <Grid x:Name="grid" RowSpacing="1">
                      <Grid.RowDefinitions>
                          <RowDefinition Height="*" />
                          <RowDefinition Height="1" />
                      </Grid.RowDefinitions>
                      . . .
                      . . .
                      <Label LineBreakMode="NoWrap"
                             Style="{StaticResource LabelStyle}"
                             Text="{Binding ContactName}"/>
                      <Label Grid.Row="1"
                             Grid.Column="0"
                             Style="{StaticResource LabelStyle}"
                             Text="{Binding ContactNumber}"/>
                </Grid>
                  . . .
                  . . .
            </Grid>
            </DataTemplate>
        </syncfusion:SfListView.ItemTemplate>
    </syncfusion:SfListView>
</Grid>