ChartBaseView.Legend Property

Gets or sets the chart legend.

Namespace: DevExpress.XamarinForms.Charts

Assembly: DevExpress.XamarinForms.Charts.dll

NuGet Package: DevExpress.XamarinForms.Charts

Declaration

public Legend Legend { get; set; }

Property Value

Type	Description
Legend	The Legend object that stores chart legend settings.

Remarks

A legend is a chart element that identifies series, series points, constant lines and strips displayed on the chart diagram.

A legend content depends on the chart type:

• ChartView

  Legend items identify series and display their names (SeriesBase.DisplayName). To show or hide an individual series in a legend, use the SeriesBase.VisibleInLegend property.

• PieChartView

  Legend items identify series points. You can use the SeriesBase.LegendTextPattern property to change the text format of legend items.

To show a constant line or strip in a legend, set the ConstantLineBase.VisibleInLegend or StripBase.VisibleInLegend property to true. To specify a constant line or strip description to be shown in the legend, use the ConstantLineBase.LegendText or StripBase.LegendText property.

To add a legend to a chart, assign a Legend object with the specified legend settings to the ChartBaseView.Legend property.

Legend Layout and Position

Legend items can be displayed in a column or row. Use the Legend.Orientation property to control the legend layout.

Property Value	Result
Legend.Orientation = TopToBottom
Legend.Orientation = LeftToRight

You can modify the vertical and horizontal position of a legend, and place a legend inside or outside a chart diagram. To set the legend position, use the Legend.VerticalPosition and Legend.HorizontalPosition properties. The following table shows some examples of how these properties work.

Property Values	Result
VerticalPosition = Top HorizontalPosition = Right
VerticalPosition = TopOutside HorizontalPosition = RightOutside
VerticalPosition = BottomOutside HorizontalPosition = Center

Legend Appearance

To customize the legend appearance, assign the LegendStyle object to the Legend.Style property. Use the LegendStyle object’s properties to change the legend background color and border, size of legend markers, item text color and size, and distances between legend elements (between items, between an item marker and text, between legend edges and items, between legend edges and chart border).

Example

This example shows how to add a legend to a pie chart and adjust the legend settings.

1. To add a legend to the chart, assign a Legend object to the PieChartView.Legend property and use the following properties of this object to specify the legend orientation and position:

   • Orientation - display legend items in a row, from left to right.
   • VerticalPosition - place the legend above the chart diagram.
   • HorizontalPosition - align the legend horizontally to the center.

2. Set the Legend.Style property to a LegendStyle object and specify the following properties of this object to configure the legend appearance:

   • BorderColor and BorderThickness - configure the legend border.
   • BackgroundColor - specify the background color.
   • MarkerSize and TextIndent - change the size of markers, and set the distance between an item text and marker.
   • ItemsHorizontalIndent - specify the distance between legend items.
   • Padding - specify the distance between legend edges and content.
   • TextStyle - change the item text color and size.

3. To exclude points of the chart’s first series from the legend, set the VisibleInLegend property of this series to false.

XAML

<dxc:PieChartView x:Name="chartView">
    <dxc:PieChartView.Series>
        <dxc:DonutSeries Data="{Binding SecuritiesByTypes}" VisibleInLegend="False"/>
        <dxc:DonutSeries Data="{Binding SecuritiesByRisk}"/>
    </dxc:PieChartView.Series>
    <dxc:PieChartView.Legend>
        <dxc:Legend Orientation="LeftToRight"
                    VerticalPosition="TopOutside"
                    HorizontalPosition="Center">
            <dxc:Legend.Style>
                <dxc:LegendStyle BorderColor="LightGray" BorderThickness="3"
                                 BackgroundColor="Gray"
                                 MarkerSize="30" TextIndent="10"
                                 ItemsHorizontalIndent="50"
                                 Padding="150,150,10,10">
                    <dxc:LegendStyle.TextStyle>
                        <dxc:TextStyle Color="White" Size="24"/>
                    </dxc:LegendStyle.TextStyle>
                </dxc:LegendStyle>
            </dxc:Legend.Style>
        </dxc:Legend>
    </dxc:PieChartView.Legend>
</dxc:PieChartView>

C#

using Xamarin.Forms;
using DevExpress.XamarinForms.Charts;
// ...

chartView.Legend = new Legend()
{
    Orientation = LegendOrientation.LeftToRight,
    VerticalPosition = LegendVerticalPosition.TopOutside,
    HorizontalPosition = LegendHorizontalPosition.Center,
    Style = new LegendStyle() {
        BorderColor = Color.LightGray,
        BorderThickness = 3,
        BackgroundColor = Color.Gray,
        MarkerSize = 30,
        TextIndent = 10,
        ItemsHorizontalIndent = 50,
        Padding = new Padding(150, 150, 10, 10),
        TextStyle = new TextStyle() {
            Color = Color.White,
            Size = 24
        }
    }
};