toolbar item android Xamarin

setting.xaml

  <ToolbarItem
            Order="Primary"
            AutomationId="EmailButton"
            Command="{Binding MailCommand}"
            Priority="1" >
            <ToolbarItem.IconImageSource>
                <FontImageSource
                    FontFamily="{StaticResource FontAwesomeSolidFontFamily}"
                    Glyph="{x:Static constants:AppConstant.MailIcon}"
                    Color="{DynamicResource TertiaryTextColor}"
                />
            </ToolbarItem.IconImageSource>
            </ToolbarItem>