Legend

17 Feb 202224 minutes to read

The legend is used to provide the information about the heat map cell. You can enable the legend by setting the visible property to true.

<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-palettesettings>
        <e-palettes>
            <e-palette value="0" color="#C2E7EC"></e-palette>
            <e-palette value="10" color="#AEDFE6"></e-palette>
            <e-palette value="20" color="#9AD7E0"></e-palette>
            <e-palette value="30" color="#72C7D4"></e-palette>
            <e-palette value="40" color="#5EBFCE"></e-palette>
            <e-palette value="50" color="#4AB7C8"></e-palette>
            <e-palette value="60" color="#309DAE"></e-palette>
            <e-palette value="70" color="#2B8C9B"></e-palette>
            <e-palette value="80" color="#206974"></e-palette>
            <e-palette value="90" color="#15464D"></e-palette>
            <e-palette value="100" color="#000000"></e-palette>
        </e-palettes>
  </e-heatmap-palettesettings>
  <e-heatmap-legendsettings position="Right"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult Legend()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
         };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }

Legend types

Heat map supports two legend types: Gradient and list type.

  • Gradient - This is a continuous color legend with smooth color transition between palette color values.
  • List - List is a fixed color legend. Each palette color information is shown separately in the list item.

You can change the legend type by using the type property in the paletteSettings property.

<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-palettesettings type="Fixed"></e-heatmap-palettesettings>
  <e-heatmap-cellsettings showlabel="false"></e-heatmap-cellsettings>
  <e-heatmap-legendsettings position="Right"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult LegendTypes()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
         };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         ViewBag.textStyle = new { fontStyle = "Italic",fontFamily = "Segoe UI"};
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }

Placement

You can place the legend at left, right, top, or bottom to the heat map layout by using the position property. The legend is positioned at the right to the heat map by default.

<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-legendsettings position="Top"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult Placement()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
         };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }

Alignment

You can align the legend as center, far, or near to the heat map using the alignment property.

<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-legendsettings position="Right" alignment="Near" height="150px"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult Alignment()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
         };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }

Legend dimensions

You can change the legend dimensions with values in pixels or percentage by using thewidth and height properties.

<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-legendsettings position="Right" height="150px"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult Dimensions()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
         };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }

Paging for legend

Paging is available only for the list type legend in the heat map, and it can be enabled by default,when the legend items exceed the legend bounds. You can view each legend items by navigating between the pages using navigation buttons.

<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-palettesettings type="Fixed">
        <e-palettes>
            <e-palette value="0" color="#C2E7EC"></e-palette>
            <e-palette value="10" color="#AEDFE6"></e-palette>
            <e-palette value="20" color="#9AD7E0"></e-palette>
            <e-palette value="25" color="#86CFDA"></e-palette>
            <e-palette value="30" color="#72C7D4"></e-palette>
            <e-palette value="40" color="#5EBFCE"></e-palette>
            <e-palette value="50" color="#4AB7C8"></e-palette>
            <e-palette value="55" color="#36AFC2"></e-palette>
            <e-palette value="60" color="#309DAE"></e-palette>
            <e-palette value="70" color="#2B8C9B"></e-palette>
            <e-palette value="75" color="#257A87"></e-palette>
            <e-palette value="80" color="#206974"></e-palette>
            <e-palette value="85" color="#1B5761"></e-palette>
            <e-palette value="90" color="#15464D"></e-palette>
            <e-palette value="100" color="#000000"></e-palette>
        </e-palettes>
  </e-heatmap-palettesettings>
  <e-heatmap-legendsettings position="Right" height="150px"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult Paging()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
         };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }

Smart Legend

Smart legend is another way of showing list type legend with responsiveness and readability, when the palette has more number of items. You can enable this smart legend by using the enableSmartLegend property when the palette type is set to Fixed.

In smart legend, you can change the display type of legend labels by using the labelDisplayType property.

The following are the legend label display types:

  • All: Displays all labels in the legend.
  • Edge: Displays the legend labels only at extreme ends.
  • None: None of the labels are displayed. The tooltip will appear for this type of label display when hovering over the legend item.
<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-palettesettings type="Fixed">
        <e-palettes>
            <e-palette value="0" color="#C2E7EC"></e-palette>
            <e-palette value="10" color="#AEDFE6"></e-palette>
            <e-palette value="20" color="#9AD7E0"></e-palette>
            <e-palette value="30" color="#72C7D4"></e-palette>
            <e-palette value="40" color="#5EBFCE"></e-palette>
            <e-palette value="50" color="#4AB7C8"></e-palette>
            <e-palette value="60" color="#309DAE"></e-palette>
            <e-palette value="70" color="#2B8C9B"></e-palette>
            <e-palette value="80" color="#206974"></e-palette>
            <e-palette value="90" color="#15464D"></e-palette>
            <e-palette value="100" color="#000000"></e-palette>
        </e-palettes>
  </e-heatmap-palettesettings>
  <e-heatmap-cellsettings showLabel="false"></e-heatmap-cellsettings>
  <e-heatmap-legendsettings position="Bottom" width="75%" toggleVisibility="true" enableSmartLegend="true"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult Legend()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
    };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }

Legend Selection

In the HeatMap, the legend selection is used to toggle the visibility of cell for viewing the specific range value. You can enable the legend selection using the toggleVisibility property.

<ejs-heatmap id='container' dataSource="ViewBag.dataSource">
  <e-heatmap-titlesettings text="Sales Revenue per Employee (in 1000 US$)" textStyle="ViewBag.textStyle">
  </e-heatmap-titlesettings>
  <e-heatmap-xaxis labels="ViewBag.xLabels">
  </e-heatmap-xaxis>
  <e-heatmap-yaxis labels="ViewBag.yLabels">
  </e-heatmap-yaxis>
  <e-heatmap-palettesettings type="Fixed">
        <e-palettes>
            <e-palette value="0" color="#C2E7EC"></e-palette>
            <e-palette value="10" color="#AEDFE6"></e-palette>
            <e-palette value="20" color="#9AD7E0"></e-palette>
            <e-palette value="30" color="#72C7D4"></e-palette>
            <e-palette value="40" color="#5EBFCE"></e-palette>
            <e-palette value="50" color="#4AB7C8"></e-palette>
            <e-palette value="60" color="#309DAE"></e-palette>
            <e-palette value="70" color="#2B8C9B"></e-palette>
            <e-palette value="80" color="#206974"></e-palette>
            <e-palette value="90" color="#15464D"></e-palette>
            <e-palette value="100" color="#000000"></e-palette>
        </e-palettes>
  </e-heatmap-palettesettings>
  <e-heatmap-cellsettings showLabel="false"></e-heatmap-cellsettings>
  <e-heatmap-legendsettings position="Bottom" width="75%" enableSmartLegend="true" toggleVisibility="true"></e-heatmap-legendsettings>
</ejs-heatmap>
public ActionResult Legend()
{
    ViewBag.textStyle = new
     {
         size= "15px",
         fontWeight= "500",
         fontStyle= "Normal",
         fontFamily= "Segoe UI"
    };
         string[] xlabels = new string[12] { "Nancy", "Andrew", "Janet", "Margaret", "Steven", "Michael", "Robert", "Laura", "Anne", "Paul", "Karin", "Mario" };
         ViewBag.xLabels = xlabels;
         string[] yLabels = new string[6] { "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat" };
         ViewBag.yLabels = yLabels;
         ViewBag.dataSource = GetDataSource();
         return View();
}

 private int[,] GetDataSource()
 {
     int[,] data = new int[,]
            {
                {73, 39, 26, 39, 94, 0},
                {93, 58, 53, 38, 26, 68},
                {99, 28, 22, 4, 66, 90},
                {14, 26, 97, 69, 69, 3},
                {7, 46, 47, 47, 88, 6},
                {41, 55, 73, 23, 3, 79},
                {56, 69, 21, 86, 3, 33},
                {45, 7, 53, 81, 95, 79},
                {60, 77, 74, 68, 88, 51},
                {25, 25, 10, 12, 78, 14},
                {25, 56, 55, 58, 12, 82},
                {74, 33, 88, 23, 86, 59}
            };
            return data;
 }