Public Class Form1
    Inherits Form
    
    Public Sub New()
        MyBase.New
        InitializeComponent
    End Sub
    
    Private Shared vendors As List(Of SmartPhoneVendor) = New List(Of SmartPhoneVendor)
    Private Shared LegendIconImage As Image = Properties.Resources.usa
    Private customSeries As Series
    
    Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs)
        vendors = SmartPhoneVendors
        ' Set a Data Source
        flexChart1.DataSource = vendors
        flexChart1.BindingX = "Name"
        flexChart1.Binding = "Sales"
        flexChart1.Header.Style.Font = New Font(FontFamily.GenericSansSerif, 15)
        flexChart1.Header.Content = "Top Smartphone Vendors"
        flexChart1.Series.Clear
        'Add custom series
        Me.customSeries = New SeriesWithPointLegendItems
        Me.customSeries.Name = "Sales in USA"
        flexChart1.Series.Add(Me.customSeries)
        flexChart1.Legend.Position = Position.Left
        flexChart1.ToolTip.Content = "{seriesName}"& vbCrLf&"{value}"
    End Sub
    
    Public Class SeriesWithPointLegendItems
        Inherits Series
        Implements ISeries
        
        Function ISeries_GetLegendItemImageSource_((ByVal index As Integer, ByRef imageSize As C1.Chart._Size) As Object Implements ISeries.GetLegendItemImageSource.(
            ' Original images/logos are all 50x50 pixels.
            ' Here they are replaced with new images where a 5 pixel border is added
            ' around the logos.
            imageSize.Height = 60
            imageSize.Width = 60
            Dim vendor As SmartPhoneVendor = vendors.ElementAt(index)
            If ((Not (LegendIconImage) Is Nothing)  _
                        AndAlso (LegendIconImage.Width <> 60)) Then
                Dim bmp As Bitmap = New Bitmap(60, 60)
                Dim sb As SolidBrush = New SolidBrush(vendor.Color)
                Dim g As Graphics = Graphics.FromImage(bmp)
                Dim r As Rectangle = New Rectangle(0, 0, CType(imageSize.Width,Integer), CType(imageSize.Height,Integer))
                Dim p As Pen = New Pen(sb)
                g.DrawRectangle(p, r)
                g.FillRectangle(sb, r)
                Dim ci As Point = New Point(CType((0.5  _
                                * (imageSize.Width - LegendIconImage.Width)),Integer), CType((0.5  _
                                * (imageSize.Height - LegendIconImage.Height)),Integer))
                g.DrawImage(LegendIconImage, ci)
                LegendIconImage = bmp
            End If
            
            ' Keep the original size of the logo bitmaps, but reduce their size if the chart window
            ' is too small to display the bitmaps properly.
            Dim bounds As Size = Me.Chart.ClientSize
            Dim divadj As Double = 12
            Dim fracHeight As Double = (bounds.Height / divadj)
            If (fracHeight < imageSize.Height) Then
                imageSize.Height = fracHeight
            End If
            
            imageSize.Width = fracHeight
            Return LegendIconImage
        End Function
    End Class
    
Private Shared Function SmartPhoneVendors() As List(Of SmartPhoneVendor)
    vendors.Add(New SmartPhoneVendor() With {.Name = "Apple", .Color = Color.FromArgb(136, 189, 230), .Sales = 350})
    vendors.Add(New SmartPhoneVendor() With {.Name = "LG", .Color = Color.FromArgb(251, 178, 88), .Sales = 120})
    vendors.Add(New SmartPhoneVendor() With {.Name = "Samsung", .Color = Color.FromArgb(188, 153, 199), .Sales = 280})
    vendors.Add(New SmartPhoneVendor() With {.Name = "Xiaomi", .Color = Color.FromArgb(240, 126, 110), .Sales = 68})
    Return vendors
End Function
    
Public Class SmartPhoneVendor

    Public Property Name As String

    Public Property Sales As Double

    Public Property Color As Color
End Class
    
End Class

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        static List<SmartPhoneVendor> vendors = new List<SmartPhoneVendor>();
        static Image LegendIconImage = Properties.Resources.usa;
        Series customSeries;
        private void Form1_Load(object sender, EventArgs e)
        {
            vendors = SmartPhoneVendors();
            // Set a Data Source
            flexChart1.DataSource = vendors;
            flexChart1.BindingX = "Name";
            flexChart1.Binding = "Sales";
            flexChart1.Header.Style.Font = new Font(FontFamily.GenericSansSerif, 15);
            flexChart1.Header.Content = "Top Smartphone Vendors";
            flexChart1.Series.Clear();

            //Add custom series
            customSeries = new SeriesWithPointLegendItems();
            customSeries.Name = "Sales in USA";
            flexChart1.Series.Add(customSeries);
            flexChart1.Legend.Position = Position.Left;
            flexChart1.ToolTip.Content = "{seriesName}\r\n{value}";
        }
        public class SeriesWithPointLegendItems : Series, ISeries
        {
            object ISeries.GetLegendItemImageSource(int index, ref C1.Chart._Size imageSize)
            {
                {
                    // Original images/logos are all 50x50 pixels.
                    // Here they are replaced with new images where a 5 pixel border is added
                    // around the logos.
                    imageSize.Height = 60;
                    imageSize.Width = 60;

                    SmartPhoneVendor vendor = vendors.ElementAt(index);
                    if (LegendIconImage != null && LegendIconImage.Width != 60)
                    {
                        Bitmap bmp = new Bitmap(60, 60);
                        using (SolidBrush sb = new SolidBrush(vendor.Color))
                        {
                            using (Graphics g = Graphics.FromImage(bmp))
                            {
                                Rectangle r = new Rectangle(0, 0, (int)imageSize.Width, (int)imageSize.Height);
                                using (Pen p = new Pen(sb))
                                {
                                    g.DrawRectangle(p, r);
                                }
                                g.FillRectangle(sb, r);

                                Point ci = new Point((int)(0.5 * (imageSize.Width - LegendIconImage.Width)),
                                    (int)(0.5 * (imageSize.Height - LegendIconImage.Height)));
                                g.DrawImage(LegendIconImage, ci);
                            }
                        }
                        LegendIconImage = bmp;
                    }
                    // Keep the original size of the logo bitmaps, but reduce their size if the chart window
                    // is too small to display the bitmaps properly.
                    Size bounds = this.Chart.ClientSize;
                    double divadj = (bounds.Height > 800) ? 12 : 25;
                    double fracHeight = bounds.Height / divadj;
                    if (fracHeight < imageSize.Height)
                        imageSize.Width = imageSize.Height = fracHeight;
                    return LegendIconImage;
                }
            }
        }
        private static List<SmartPhoneVendor> SmartPhoneVendors()
        {

            vendors.Add(new SmartPhoneVendor()
            {
                Name = "Apple",
                Color = Color.FromArgb(136, 189, 230),
                Sales = 350,
            });
            vendors.Add(new SmartPhoneVendor()
            {
                Name = "LG",
                Color = Color.FromArgb(251, 178, 88),
                Sales = 120,
            });
           
            vendors.Add(new SmartPhoneVendor()
            {
                Name = "Samsung",
                Color = Color.FromArgb(188, 153, 199),
                Sales = 280,
            });
          
            vendors.Add(new SmartPhoneVendor()
            {
                Name = "Xiaomi",
                Color = Color.FromArgb(240, 126, 110),
                Sales = 68,
            });

            return vendors;
        }
        public class SmartPhoneVendor
        {
            public string Name { get; set; }
            public double Sales { get; set; }
            public Color Color { get; set; }
        }
    }