Legend

14 Nov 202224 minutes to read

Legend is a key used in smithchart, that contains symbol and descriptions. It provides valuable information for interpreting what the smithchart is displaying and can be represented in various colors, shapes or other identifiers based on the data. In simple words, we can define that legend is used to denote the series rendered in the smithchart.

Position and Alignment

By default visibility of the legend is false. To enable the legend, set visible as true in legendSettings. Default position for the legend is bottom. By using [position] property, you can change the position of the legend. You can either place the legend at bottom, top, right and left side of the smithchart. To use the legend in smithchart, you need to import and inject the SmithchartLegend from chart.

@using Syncfusion.EJ2;
@using Syncfusion.EJ2.Charts;
<div id="control-section">
 <ejs-smithchart id="smithchart" loaded="loaded">
  <e-smithchart-legendsettings visible="true" position="Top" ></e-smithchart-legendsettings>
        <e-smithchart-smithchartseriescollection>
            <e-smithchart-smithchartseries name="Transmission1"></e-smithchart-smithchartseries>
            <e-smithchart-smithchartseries name="Transmission2"></e-smithchart-smithchartseries>
        </e-smithchart-smithchartseriescollection>
</ejs-smithchart>
</div>
<script>
        function loaded(args) {
            window.smithchart = args.smithchart;
            args.smithchart.series[0].points = [
                { resistance: 10, reactance: 25 }, { resistance: 8, reactance: 6 },
                { resistance: 6, reactance: 4.5 }, { resistance: 4.5, reactance: 2 },
                { resistance: 3.5, reactance: 1.6 }, { resistance: 2.5, reactance: 1.3 },
                { resistance: 2, reactance: 1.2 }, { resistance: 1.5, reactance: 1 },
                { resistance: 1, reactance: 0.8 }, { resistance: 0.5, reactance: 0.4 },
                { resistance: 0.3, reactance: 0.2 }, { resistance: 0, reactance: 0.15 },
            ];
            args.smithchart.series[1].points = [{ resistance: 20, reactance: -50 }, { resistance: 10, reactance: -10 },
                { resistance: 9, reactance: -4.5 }, { resistance: 8, reactance: -3.5 },
                { resistance: 7, reactance: -2.5 }, { resistance: 6, reactance: -1.5 },
                { resistance: 5, reactance: -1 }, { resistance: 4.5, reactance: -0.5 },
                { resistance: 3.5, reactance: 0 }, { resistance: 2.5, reactance: 0.4 },
                { resistance: 2, reactance: 0.5 }, { resistance: 1.5, reactance: 0.5 },
                { resistance: 1, reactance: 0.4 }, { resistance: 0.5, reactance: 0.2 },
                { resistance: 0.3, reactance: 0.1 }, { resistance: 0, reactance: 0.05 },];
            args.smithchart.loaded = null;
            args.smithchart.refresh();
        }
    </script>
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using EJ2_Core_Application.Models;
using Newtonsoft.Json;

namespace EJ2_Core_Application.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }
    }
}

Other than these positions, you can place the legend anywhere in the smithchart. To achieve this, you have to set position as custom in legendSettings and specify the x and y coordinates using the x and y properties in the location.

@using Syncfusion.EJ2;
@using Syncfusion.EJ2.Charts;
<div id="control-section">
 <ejs-smithchart id="smithchart" loaded="loaded">
  <e-smithchart-legendsettings visible="true" position="Custom">
  <e-smithchart-legendsettings-location x=80 y=90></<e-smithchart-legendsettings-location>
  </e-smithchart-legendsettings>
        <e-smithchart-smithchartseriescollection>
            <e-smithchart-smithchartseries name="Transmission1"></e-smithchart-smithchartseries>
            <e-smithchart-smithchartseries name="Transmission2"></e-smithchart-smithchartseries>
        </e-smithchart-smithchartseriescollection>
</ejs-smithchart>
</div>
<script>
        function loaded(args) {
            window.smithchart = args.smithchart;
            args.smithchart.series[0].points = [
                { resistance: 10, reactance: 25 }, { resistance: 8, reactance: 6 },
                { resistance: 6, reactance: 4.5 }, { resistance: 4.5, reactance: 2 },
                { resistance: 3.5, reactance: 1.6 }, { resistance: 2.5, reactance: 1.3 },
                { resistance: 2, reactance: 1.2 }, { resistance: 1.5, reactance: 1 },
                { resistance: 1, reactance: 0.8 }, { resistance: 0.5, reactance: 0.4 },
                { resistance: 0.3, reactance: 0.2 }, { resistance: 0, reactance: 0.15 },
            ];
            args.smithchart.series[1].points = [{ resistance: 20, reactance: -50 }, { resistance: 10, reactance: -10 },
                { resistance: 9, reactance: -4.5 }, { resistance: 8, reactance: -3.5 },
                { resistance: 7, reactance: -2.5 }, { resistance: 6, reactance: -1.5 },
                { resistance: 5, reactance: -1 }, { resistance: 4.5, reactance: -0.5 },
                { resistance: 3.5, reactance: 0 }, { resistance: 2.5, reactance: 0.4 },
                { resistance: 2, reactance: 0.5 }, { resistance: 1.5, reactance: 0.5 },
                { resistance: 1, reactance: 0.4 }, { resistance: 0.5, reactance: 0.2 },
                { resistance: 0.3, reactance: 0.1 }, { resistance: 0, reactance: 0.05 },];
            args.smithchart.loaded = null;
            args.smithchart.refresh();
        }
    </script>
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using EJ2_Core_Application.Models;
using Newtonsoft.Json;

namespace EJ2_Core_Application.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }
    }
}

Legend Alignment

Other than positioning the legend in the smithchart, you can customize its alignment also. By default, legend is aligned at center. Using the [alignment] property, you can align the legend in near and far locations of the smithchart.

@using Syncfusion.EJ2;
@using Syncfusion.EJ2.Charts;
<div id="control-section">
 <ejs-smithchart id="smithchart" loaded="loaded">
  <e-smithchart-legendsettings visible="true" position="Top" alignment= 'Near'></e-smithchart-legendsettings>
        <e-smithchart-smithchartseriescollection>
            <e-smithchart-smithchartseries name="Transmission1"></e-smithchart-smithchartseries>
            <e-smithchart-smithchartseries name="Transmission2"></e-smithchart-smithchartseries>
        </e-smithchart-smithchartseriescollection>
</ejs-smithchart>
</div>
<script>
        function loaded(args) {
            window.smithchart = args.smithchart;
            args.smithchart.series[0].points = [
                { resistance: 10, reactance: 25 }, { resistance: 8, reactance: 6 },
                { resistance: 6, reactance: 4.5 }, { resistance: 4.5, reactance: 2 },
                { resistance: 3.5, reactance: 1.6 }, { resistance: 2.5, reactance: 1.3 },
                { resistance: 2, reactance: 1.2 }, { resistance: 1.5, reactance: 1 },
                { resistance: 1, reactance: 0.8 }, { resistance: 0.5, reactance: 0.4 },
                { resistance: 0.3, reactance: 0.2 }, { resistance: 0, reactance: 0.15 },
            ];
            args.smithchart.series[1].points = [{ resistance: 20, reactance: -50 }, { resistance: 10, reactance: -10 },
                { resistance: 9, reactance: -4.5 }, { resistance: 8, reactance: -3.5 },
                { resistance: 7, reactance: -2.5 }, { resistance: 6, reactance: -1.5 },
                { resistance: 5, reactance: -1 }, { resistance: 4.5, reactance: -0.5 },
                { resistance: 3.5, reactance: 0 }, { resistance: 2.5, reactance: 0.4 },
                { resistance: 2, reactance: 0.5 }, { resistance: 1.5, reactance: 0.5 },
                { resistance: 1, reactance: 0.4 }, { resistance: 0.5, reactance: 0.2 },
                { resistance: 0.3, reactance: 0.1 }, { resistance: 0, reactance: 0.05 },];
            args.smithchart.loaded = null;
            args.smithchart.refresh();
        }
    </script>
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using EJ2_Core_Application.Models;
using Newtonsoft.Json;

namespace EJ2_Core_Application.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }
    }
}

Customization

Legend Shape

By default, legend is rendered in the circle shape and the color of the shape is as same as series color in the smithchart. Using the property [shape] in legend settings, you can change the icon shape of the legend as rectangle, triangle and so on.

@using Syncfusion.EJ2;
@using Syncfusion.EJ2.Charts;
<div id="control-section">
 <ejs-smithchart id="smithchart" loaded="loaded">
  <e-smithchart-legendsettings visible="true" position="Top"shape ='Rectangle'></e-smithchart-legendsettings>
        <e-smithchart-smithchartseriescollection>
            <e-smithchart-smithchartseries name="Transmission1"></e-smithchart-smithchartseries>
            <e-smithchart-smithchartseries name="Transmission2"></e-smithchart-smithchartseries>
        </e-smithchart-smithchartseriescollection>
</ejs-smithchart>
</div>
<script>
        function loaded(args) {
            window.smithchart = args.smithchart;
            args.smithchart.series[0].points = [
                { resistance: 10, reactance: 25 }, { resistance: 8, reactance: 6 },
                { resistance: 6, reactance: 4.5 }, { resistance: 4.5, reactance: 2 },
                { resistance: 3.5, reactance: 1.6 }, { resistance: 2.5, reactance: 1.3 },
                { resistance: 2, reactance: 1.2 }, { resistance: 1.5, reactance: 1 },
                { resistance: 1, reactance: 0.8 }, { resistance: 0.5, reactance: 0.4 },
                { resistance: 0.3, reactance: 0.2 }, { resistance: 0, reactance: 0.15 },
            ];
            args.smithchart.series[1].points = [{ resistance: 20, reactance: -50 }, { resistance: 10, reactance: -10 },
                { resistance: 9, reactance: -4.5 }, { resistance: 8, reactance: -3.5 },
                { resistance: 7, reactance: -2.5 }, { resistance: 6, reactance: -1.5 },
                { resistance: 5, reactance: -1 }, { resistance: 4.5, reactance: -0.5 },
                { resistance: 3.5, reactance: 0 }, { resistance: 2.5, reactance: 0.4 },
                { resistance: 2, reactance: 0.5 }, { resistance: 1.5, reactance: 0.5 },
                { resistance: 1, reactance: 0.4 }, { resistance: 0.5, reactance: 0.2 },
                { resistance: 0.3, reactance: 0.1 }, { resistance: 0, reactance: 0.05 },];
            args.smithchart.loaded = null;
            args.smithchart.refresh();
        }
    </script>
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using EJ2_Core_Application.Models;
using Newtonsoft.Json;

namespace EJ2_Core_Application.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }
    }
}

Legend Size

By default, legend takes 20% - 25% of the chart’s height horizontally, when it is placed on top or bottom position and 20% - 25% of the width vertically, while placing on left or right position of the chart. You can change this default legend size by using the [width] and [height] property of the legendSettings.

@using Syncfusion.EJ2;
@using Syncfusion.EJ2.Charts;
<div id="control-section">
 <ejs-smithchart id="smithchart" loaded="loaded">
  <e-smithchart-legendsettings visible="true" position="Top" itemPadding= 5 shapePadding= 10></e-smithchart-legendsettings>
        <e-smithchart-smithchartseriescollection>
            <e-smithchart-smithchartseries name="Transmission1"></e-smithchart-smithchartseries>
            <e-smithchart-smithchartseries name="Transmission2"></e-smithchart-smithchartseries>
        </e-smithchart-smithchartseriescollection>
</ejs-smithchart>
</div>
<script>
        function loaded(args) {
            window.smithchart = args.smithchart;
            args.smithchart.series[0].points = [
                { resistance: 10, reactance: 25 }, { resistance: 8, reactance: 6 },
                { resistance: 6, reactance: 4.5 }, { resistance: 4.5, reactance: 2 },
                { resistance: 3.5, reactance: 1.6 }, { resistance: 2.5, reactance: 1.3 },
                { resistance: 2, reactance: 1.2 }, { resistance: 1.5, reactance: 1 },
                { resistance: 1, reactance: 0.8 }, { resistance: 0.5, reactance: 0.4 },
                { resistance: 0.3, reactance: 0.2 }, { resistance: 0, reactance: 0.15 },
            ];
            args.smithchart.series[1].points = [{ resistance: 20, reactance: -50 }, { resistance: 10, reactance: -10 },
                { resistance: 9, reactance: -4.5 }, { resistance: 8, reactance: -3.5 },
                { resistance: 7, reactance: -2.5 }, { resistance: 6, reactance: -1.5 },
                { resistance: 5, reactance: -1 }, { resistance: 4.5, reactance: -0.5 },
                { resistance: 3.5, reactance: 0 }, { resistance: 2.5, reactance: 0.4 },
                { resistance: 2, reactance: 0.5 }, { resistance: 1.5, reactance: 0.5 },
                { resistance: 1, reactance: 0.4 }, { resistance: 0.5, reactance: 0.2 },
                { resistance: 0.3, reactance: 0.1 }, { resistance: 0, reactance: 0.05 },];
            args.smithchart.loaded = null;
            args.smithchart.refresh();
        }
    </script>
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using EJ2_Core_Application.Models;
using Newtonsoft.Json;

namespace EJ2_Core_Application.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }
    }
}

Padding

You can customize the space between two legend items and space between legend shape and text as per your requirement. For customizing the space between two legend items, you can use [itemPadding] property. To control space between legend shape and text, you can use [shapePadding] property.

@using Syncfusion.EJ2;
@using Syncfusion.EJ2.Charts;
<div id="control-section">
 <ejs-smithchart id="smithchart" loaded="loaded">
  <e-smithchart-legendsettings visible="true" position="Top" height=100 width=200></e-smithchart-legendsettings>
        <e-smithchart-smithchartseriescollection>
            <e-smithchart-smithchartseries name="Transmission1"></e-smithchart-smithchartseries>
            <e-smithchart-smithchartseries name="Transmission2"></e-smithchart-smithchartseries>
        </e-smithchart-smithchartseriescollection>
</ejs-smithchart>
</div>
<script>
        function loaded(args) {
            window.smithchart = args.smithchart;
            args.smithchart.series[0].points = [
                { resistance: 10, reactance: 25 }, { resistance: 8, reactance: 6 },
                { resistance: 6, reactance: 4.5 }, { resistance: 4.5, reactance: 2 },
                { resistance: 3.5, reactance: 1.6 }, { resistance: 2.5, reactance: 1.3 },
                { resistance: 2, reactance: 1.2 }, { resistance: 1.5, reactance: 1 },
                { resistance: 1, reactance: 0.8 }, { resistance: 0.5, reactance: 0.4 },
                { resistance: 0.3, reactance: 0.2 }, { resistance: 0, reactance: 0.15 },
            ];
            args.smithchart.series[1].points = [{ resistance: 20, reactance: -50 }, { resistance: 10, reactance: -10 },
                { resistance: 9, reactance: -4.5 }, { resistance: 8, reactance: -3.5 },
                { resistance: 7, reactance: -2.5 }, { resistance: 6, reactance: -1.5 },
                { resistance: 5, reactance: -1 }, { resistance: 4.5, reactance: -0.5 },
                { resistance: 3.5, reactance: 0 }, { resistance: 2.5, reactance: 0.4 },
                { resistance: 2, reactance: 0.5 }, { resistance: 1.5, reactance: 0.5 },
                { resistance: 1, reactance: 0.4 }, { resistance: 0.5, reactance: 0.2 },
                { resistance: 0.3, reactance: 0.1 }, { resistance: 0, reactance: 0.05 },];
            args.smithchart.loaded = null;
            args.smithchart.refresh();
        }
    </script>
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using EJ2_Core_Application.Models;
using Newtonsoft.Json;

namespace EJ2_Core_Application.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }
    }
}

Toggle Visibility

By default series name is displayed in the legend. You can collapse the visibility of the series by clicking the legend for the particular series. You can toggle the series visibility as true or false using the [toggleVisibility] property. By default it is true.

@using Syncfusion.EJ2;
@using Syncfusion.EJ2.Charts;
<div id="control-section">
 <ejs-smithchart id="smithchart" loaded="loaded">
  <e-smithchart-legendsettings visible="true" position="Top" toggleVisibility= true></e-smithchart-legendsettings>
        <e-smithchart-smithchartseriescollection>
            <e-smithchart-smithchartseries name="Transmission1"></e-smithchart-smithchartseries>
            <e-smithchart-smithchartseries name="Transmission2"></e-smithchart-smithchartseries>
        </e-smithchart-smithchartseriescollection>
</ejs-smithchart>
</div>
<script>
        function loaded(args) {
            window.smithchart = args.smithchart;
            args.smithchart.series[0].points = [
                { resistance: 10, reactance: 25 }, { resistance: 8, reactance: 6 },
                { resistance: 6, reactance: 4.5 }, { resistance: 4.5, reactance: 2 },
                { resistance: 3.5, reactance: 1.6 }, { resistance: 2.5, reactance: 1.3 },
                { resistance: 2, reactance: 1.2 }, { resistance: 1.5, reactance: 1 },
                { resistance: 1, reactance: 0.8 }, { resistance: 0.5, reactance: 0.4 },
                { resistance: 0.3, reactance: 0.2 }, { resistance: 0, reactance: 0.15 },
            ];
            args.smithchart.series[1].points = [{ resistance: 20, reactance: -50 }, { resistance: 10, reactance: -10 },
                { resistance: 9, reactance: -4.5 }, { resistance: 8, reactance: -3.5 },
                { resistance: 7, reactance: -2.5 }, { resistance: 6, reactance: -1.5 },
                { resistance: 5, reactance: -1 }, { resistance: 4.5, reactance: -0.5 },
                { resistance: 3.5, reactance: 0 }, { resistance: 2.5, reactance: 0.4 },
                { resistance: 2, reactance: 0.5 }, { resistance: 1.5, reactance: 0.5 },
                { resistance: 1, reactance: 0.4 }, { resistance: 0.5, reactance: 0.2 },
                { resistance: 0.3, reactance: 0.1 }, { resistance: 0, reactance: 0.05 },];
            args.smithchart.loaded = null;
            args.smithchart.refresh();
        }
    </script>
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using EJ2_Core_Application.Models;
using Newtonsoft.Json;

namespace EJ2_Core_Application.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }
    }
}