How to: Specify the Appearance of the Pie Chart Using Its Pattern at Runtime

• Nov 13, 2018
• 2 minutes to read

The following example demonstrates how to specify the appearance of series labels in the Pie chart using its text pattern.

To accomplish this at runtime, it is necessary to handle the Form.Load event and then transform series labels of the Series object to the corresponding labels of the PieSeriesLabel object.

And finally, specify the pattern for series labels using the SeriesLabelBase.TextPattern property.

View Example

Form1.cs

using System;
using System.Windows.Forms;
using DevExpress.XtraCharts;

namespace XtraChart_PointOptions {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e) {
            // Create an empty chart.
            ChartControl pieChart = new ChartControl();

            // Create a pie series.
            Series series1 = new Series("A Pie Series", ViewType.Pie);

            // Populate the series with points.
            series1.Points.Add(new SeriesPoint("Russia", 17.0752));
            series1.Points.Add(new SeriesPoint("Canada", 9.98467));
            series1.Points.Add(new SeriesPoint("USA", 9.63142));
            series1.Points.Add(new SeriesPoint("China", 9.59696));
            series1.Points.Add(new SeriesPoint("Brazil", 8.511965));
            series1.Points.Add(new SeriesPoint("Australia", 7.68685));
            series1.Points.Add(new SeriesPoint("India", 3.28759));
            series1.Points.Add(new SeriesPoint("Others", 81.2));

            // Add the series to the chart.
            pieChart.Series.Add(series1);

            // Adjust the text pattern of the series label.
            PieSeriesLabel label = (PieSeriesLabel)series1.Label;
            label.TextPattern = "{A}: {VP:P0}";

            // Detect overlapping of series labels.
            label.ResolveOverlappingMode = ResolveOverlappingMode.Default;

            // Add the chart to the form.
            pieChart.Dock = DockStyle.Fill;
            this.Controls.Add(pieChart);
        }
    }
}

Form1.vb

Imports Microsoft.VisualBasic
Imports System
Imports System.Windows.Forms
Imports DevExpress.XtraCharts

Namespace XtraChart_PointOptions
    Partial Public Class Form1
        Inherits Form
        Public Sub New()
            InitializeComponent()
        End Sub

        Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
            ' Create an empty chart.
            Dim pieChart As New ChartControl()

            ' Create a pie series.
            Dim series1 As New Series("A Pie Series", ViewType.Pie)

            ' Populate the series with points.
            series1.Points.Add(New SeriesPoint("Russia", 17.0752))
            series1.Points.Add(New SeriesPoint("Canada", 9.98467))
            series1.Points.Add(New SeriesPoint("USA", 9.63142))
            series1.Points.Add(New SeriesPoint("China", 9.59696))
            series1.Points.Add(New SeriesPoint("Brazil", 8.511965))
            series1.Points.Add(New SeriesPoint("Australia", 7.68685))
            series1.Points.Add(New SeriesPoint("India", 3.28759))
            series1.Points.Add(New SeriesPoint("Others", 81.2))

            ' Add the series to the chart.
            pieChart.Series.Add(series1)

            ' Adjust the text pattern of the series label.
            Dim label As PieSeriesLabel = CType(series1.Label, PieSeriesLabel)
            label.TextPattern = "{A}: {VP:P0}"

            ' Detect overlapping of series labels.
            label.ResolveOverlappingMode = ResolveOverlappingMode.Default

            ' Add the chart to the form.
            pieChart.Dock = DockStyle.Fill
            Me.Controls.Add(pieChart)
        End Sub
    End Class
End Namespace