Bollinger Bands

Bollinger Bands overlay displays upper and lower limits of the price movements over the time. These are volatility bands based on standard deviation, and are placed above and below a moving average. Bollinger Bands are helpful in providing a relative definition of high and low price. Prices plotted near the upper band are considered high, while prices near the lower band are low. The width of the band depicts the measure of volatility. The price values touching the top of the Bollinger Band are supposed to be over extended above the intermediate trend, and the prices touching the bottom of the Bollinger band are supposed to be over extended below the intermediate trend.

To use Bollinger Bands overlay in FinancialChart, add a FinancialChart control to your application and bind it to an appropriate data source or populate data in it through Quote Collection. ItemsSource object enables data binding or populating data in FinancialChart. BollingerBands class exposes Multiplier property, to specify standard deviations for upper and lower bands, and IndicatorBase class provides the Period property, which takes integer value for calculating Simple Moving Average for the middle band. Based on the values of these properties, data points for Bollinger Bands overlay are calculated and plotted on FinancialChart.

The following example considers stock data for a company Box Inc. over a period of time and plots Bollinger Bands overlay on the same financial chart, as shown in the image above. The example uses data from a json file, and DataService.cs class is created to access this json file.

Make sure that Build Action property of the json file is set to Embedded Resource.

XAML	Copy Code
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:local="clr-namespace:BollingerBOverlay" xmlns:c1="http://schemas.componentone.com/winfx/2006/xaml" x:Class="BollingerBOverlay.MainWindow" DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}" mc:Ignorable="d" Title="MainWindow" Height="350" Width="525"> <Grid> <c1:C1FinancialChart x:Name="financialChart" ItemsSource="{Binding Data}" Background="White" ChartType="Candlestick" BindingX="Date" ToolTipContent="{}{seriesName} {Date} {y}" Margin="6,37,4,71"> <c1:FinancialSeries Binding="High,Low,Open,Close" SeriesName="Box Inc." /> <c1:BollingerBands x:Name="bollinger" Multiplier="2" Period="20" Binding="High,Low,Close" SeriesName="Bollinger Bands" /> <c1:C1FinancialChart.AxisX> <c1:Axis LabelAngle="45" MajorUnit="3"/> </c1:C1FinancialChart.AxisX> </c1:C1FinancialChart> </Grid> </Window>

XAML

Copy Code

    <Window
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:BollingerBOverlay"
        xmlns:c1="http://schemas.componentone.com/winfx/2006/xaml" 
        x:Class="BollingerBOverlay.MainWindow"
        DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
<c1:C1FinancialChart x:Name="financialChart"
                     ItemsSource="{Binding Data}"
                     Background="White"
                     ChartType="Candlestick"
                     BindingX="Date" 
                     ToolTipContent="{}{seriesName}&#x000A;{Date} {y}" 
                     Margin="6,37,4,71">            
            <c1:FinancialSeries Binding="High,Low,Open,Close" 
                                SeriesName="Box Inc." />
            <c1:BollingerBands x:Name="bollinger" 
                               Multiplier="2" 
                               Period="20" 
                               Binding="High,Low,Close" 
                               SeriesName="Bollinger Bands" />

            <c1:C1FinancialChart.AxisX>
                <c1:Axis LabelAngle="45" MajorUnit="3"/>
            </c1:C1FinancialChart.AxisX>
        </c1:C1FinancialChart>        
    </Grid>
</Window>

Make sure to add the following references in DataService.cs:

System.Collections.Generic
System.Linq
System.Runtime.Serialization.Json
System.Reflection

DataService.vb
DataService.cs

DataService.vb

Public Class DataService
    Public Function GetData() As List(Of Quote)
        Dim path As String = "OverlayVB.Resources.box.json"
        'Replace OverlayVB by your application name       
        Dim stream = Assembly.GetExecutingAssembly().GetManifestResourceStream(path)
        Dim ser = New DataContractJsonSerializer(GetType(Quote()))
        Dim data = DirectCast(ser.ReadObject(stream), Quote())
        Return data.ToList()
    End Function
    Shared _ds As DataService
    Public Shared Function GetService() As DataService
        If _ds Is Nothing Then
            _ds = New DataService()
        End If
        Return _ds
    End Function
End Class

DataService.cs

public class DataService
{
    public List<Quote> GetData()
    {
        string path = "BollingerBOverlay.Resources.box.json";
        //Replace BollingerBOverlay by your application name       
        var stream = Assembly.GetExecutingAssembly().GetManifestResourceStream(path);
        var ser = new DataContractJsonSerializer(typeof(Quote[]));
        var data = (Quote[])ser.ReadObject(stream);
        return data.ToList();
    }
    static DataService _ds;
    public static DataService GetService()
    {
        if (_ds == null)
            _ds = new DataService();
        return _ds;
    }
}

Json Data

[
    { "date": "01/23/15", "open": 20.2, "high": 24.73, "low": 20.16, "close": 23.23, "volume": 42593223 }, 
    { "date": "01/26/15", "open": 23.67, "high": 24.39, "low": 22.5, "close": 22.6, "volume": 8677164 }, 
    { "date": "01/27/15", "open": 22, "high": 22.47, "low": 21.17, "close": 21.3, "volume": 3272512 }, 
    { "date": "01/28/15", "open": 21.62, "high": 21.84, "low": 19.6, "close": 19.78, "volume": 5047364 }, 
    { "date": "01/29/15", "open": 19.9, "high": 19.95, "low": 18.51, "close": 18.8, "volume": 3419482 }, 
    { "date": "01/30/15", "open": 18.47, "high": 19.48, "low": 18.22, "close": 18.81, "volume": 2266439 }, 
    { "date": "02/02/15", "open": 19.18, "high": 19.3, "low": 18.01, "close": 18.02, "volume": 2071168 }, 
    { "date": "02/03/15", "open": 18.22, "high": 18.64, "low": 18.12, "close": 18.24, "volume": 1587435 }, 
    { "date": "02/04/15", "open": 18.2, "high": 18.35, "low": 17, "close": 17.1, "volume": 2912224 }, 
    { "date": "02/05/15", "open": 17.3, "high": 17.31, "low": 16.41, "close": 16.66, "volume": 2682187 }, 
    { "date": "02/06/15", "open": 17.39, "high": 18.88, "low": 17.21, "close": 18.12, "volume": 3929164 }, 
    { "date": "02/09/15", "open": 18.86, "high": 19.95, "low": 18.45, "close": 19.6, "volume": 3226650 }, 
    { "date": "02/10/15", "open": 20.5, "high": 21, "low": 19.63, "close": 20.99, "volume": 2804409 }, 
    { "date": "02/11/15", "open": 20.89, "high": 21, "low": 20.2, "close": 20.96, "volume": 1698365 }, 
    { "date": "02/12/15", "open": 20.66, "high": 20.85, "low": 19.75, "close": 20.17, "volume": 1370320 }, 
    { "date": "02/13/15", "open": 20.19, "high": 20.68, "low": 20, "close": 20.18, "volume": 711951 }, 
    { "date": "02/17/15", "open": 19.5, "high": 20.1, "low": 18.8, "close": 19.05, "volume": 2093602 }, 
    { "date": "02/18/15", "open": 18.31, "high": 18.5, "low": 17.96, "close": 18, "volume": 1849490 }, 
    { "date": "02/19/15", "open": 18.33, "high": 19.25, "low": 17.91, "close": 18.96, "volume": 1311518 }, 
    { "date": "02/20/15", "open": 18.68, "high": 19.3, "low": 18.65, "close": 18.85, "volume": 1001692 }, 
    { "date": "02/23/15", "open": 18.8, "high": 18.89, "low": 18.11, "close": 18.21, "volume": 670087 }, 
    { "date": "02/24/15", "open": 18.46, "high": 19, "low": 18.27, "close": 18.83, "volume": 759263 }, 
    { "date": "02/25/15", "open": 18.83, "high": 19.48, "low": 18.47, "close": 18.67, "volume": 915580 }, 
    { "date": "02/26/15", "open": 18.64, "high": 19.2, "low": 18.64, "close": 18.94, "volume": 461283 }, 
    { "date": "02/27/15", "open": 18.8, "high": 19.12, "low": 18.55, "close": 18.66, "volume": 617199 }, 
    { "date": "03/02/15", "open": 18.66, "high": 19.09, "low": 18.65, "close": 18.79, "volume": 519605 }, 
    { "date": "03/03/15", "open": 18.79, "high": 19.21, "low": 18.45, "close": 18.59, "volume": 832415 }, 
    { "date": "03/04/15", "open": 18.64, "high": 19.05, "low": 18.32, "close": 19, "volume": 539688 }, 
    { "date": "03/05/15", "open": 19.2, "high": 19.2, "low": 18.8, "close": 19.14, "volume": 486149 }, 
    { "date": "03/06/15", "open": 19.03, "high": 19.1, "low": 18.7, "close": 18.91, "volume": 685659 }, 
    { "date": "03/09/15", "open": 18.98, "high": 20.15, "low": 18.96, "close": 19.4, "volume": 1321363 }, 
    { "date": "03/10/15", "open": 19.3, "high": 19.8, "low": 18.85, "close": 19.64, "volume": 615743 }, 
    { "date": "03/11/15", "open": 20.08, "high": 20.65, "low": 19.24, "close": 20.53, "volume": 2167167 }, 
    { "date": "03/12/15", "open": 17.17, "high": 18.2, "low": 16.76, "close": 18.2, "volume": 6837638 }, 
    { "date": "03/13/15", "open": 18.05, "high": 18.05, "low": 17.3, "close": 17.88, "volume": 1715629 }, 
    { "date": "03/16/15", "open": 17.91, "high": 18, "low": 17.01, "close": 17.13, "volume": 1321313 }, 
    { "date": "03/17/15", "open": 17.28, "high": 17.37, "low": 16.6, "close": 17.12, "volume": 1272242 }, 
    { "date": "03/18/15", "open": 17.1, "high": 17.27, "low": 16.91, "close": 17.01, "volume": 530063 }, 
    { "date": "03/19/15", "open": 17, "high": 17.28, "low": 17, "close": 17.06, "volume": 536427 }, 
    { "date": "03/20/15", "open": 17.13, "high": 17.24, "low": 16.88, "close": 17.21, "volume": 1320237 }, 
    { "date": "03/23/15", "open": 17.21, "high": 17.23, "low": 17.01, "close": 17.11, "volume": 509798 }, 
    { "date": "03/24/15", "open": 17.02, "high": 17.18, "low": 16.82, "close": 17, "volume": 962149 }, 
    { "date": "03/25/15", "open": 16.92, "high": 16.99, "low": 16.82, "close": 16.97, "volume": 565673 }, 
    { "date": "03/26/15", "open": 16.83, "high": 17.56, "low": 16.83, "close": 17.54, "volume": 884523 }, 
    { "date": "03/27/15", "open": 17.58, "high": 18.3, "low": 17.11, "close": 18.3, "volume": 705626 }, 
    { "date": "03/30/15", "open": 18.5, "high": 19.4, "low": 18.4, "close": 19.05, "volume": 1151620 }, 
    { "date": "03/31/15", "open": 19.08, "high": 20.58, "low": 18.4, "close": 19.75, "volume": 2020679 }, 
    { "date": "04/01/15", "open": 19.69, "high": 19.69, "low": 18.55, "close": 18.65, "volume": 961078 }, 
    { "date": "04/02/15", "open": 18.56, "high": 18.66, "low": 17.85, "close": 17.9, "volume": 884233 }, 
    { "date": "04/06/15", "open": 17.78, "high": 17.94, "low": 17.51, "close": 17.66, "volume": 605252 }, 
    { "date": "04/07/15", "open": 17.62, "high": 17.9, "low": 17.53, "close": 17.61, "volume": 591988 }, 
    { "date": "04/08/15", "open": 17.64, "high": 17.85, "low": 17.32, "close": 17.36, "volume": 618855 }, 
    { "date": "04/09/15", "open": 17.33, "high": 17.54, "low": 17.1, "close": 17.1, "volume": 761855 }, 
    { "date": "04/10/15", "open": 17.08, "high": 17.36, "low": 17, "close": 17.05, "volume": 568373 }, 
    { "date": "04/13/15", "open": 17.24, "high": 17.26, "low": 16.81, "close": 17.1, "volume": 667142 }, 
    { "date": "04/14/15", "open": 17.1, "high": 17.89, "low": 17.02, "close": 17.52, "volume": 870138 }, 
    { "date": "04/15/15", "open": 17.6, "high": 17.99, "low": 17.5, "close": 17.69, "volume": 530456 }, 
    { "date": "04/16/15", "open": 17.95, "high": 18, "low": 17.6, "close": 17.82, "volume": 548730 }, 
    { "date": "04/17/15", "open": 17.75, "high": 17.79, "low": 17.5, "close": 17.79, "volume": 446373 }, 
    { "date": "04/20/15", "open": 17.63, "high": 17.98, "low": 17.52, "close": 17.93, "volume": 487017 }, 
    { "date": "04/21/15", "open": 17.96, "high": 17.98, "low": 17.71, "close": 17.92, "volume": 320302 }, 
    { "date": "04/22/15", "open": 17.88, "high": 18.33, "low": 17.57, "close": 18.29, "volume": 644812 }, 
    { "date": "04/23/15", "open": 18.29, "high": 18.61, "low": 18.18, "close": 18.28, "volume": 563879 }, 
    { "date": "04/24/15", "open": 18.5, "high": 18.5, "low": 17.61, "close": 17.75, "volume": 650762 }, 
    { "date": "04/27/15", "open": 17.97, "high": 18.05, "low": 17.45, "close": 17.57, "volume": 437294 }, 
    { "date": "04/28/15", "open": 17.65, "high": 17.79, "low": 17.39, "close": 17.5, "volume": 224519 }, 
    { "date": "04/29/15", "open": 17.68, "high": 17.68, "low": 17.1, "close": 17.21, "volume": 495706 }, 
    { "date": "04/30/15", "open": 17.22, "high": 17.3, "low": 17, "close": 17.11, "volume": 391040 }, 
    { "date": "05/01/15", "open": 17.11, "high": 17.55, "low": 16.85, "close": 17.5, "volume": 563075 }, 
    { "date": "05/04/15", "open": 17.56, "high": 17.85, "low": 17.3, "close": 17.4, "volume": 253138 }, 
    { "date": "05/05/15", "open": 17.68, "high": 17.68, "low": 17.09, "close": 17.43, "volume": 290935 }, 
    { "date": "05/06/15", "open": 17.48, "high": 17.48, "low": 17, "close": 17.04, "volume": 313662 }, 
    { "date": "05/07/15", "open": 17.05, "high": 17.19, "low": 16.92, "close": 17.04, "volume": 360284 }, 
    { "date": "05/08/15", "open": 17.13, "high": 17.21, "low": 16.91, "close": 17.1, "volume": 297653 }, 
    { "date": "05/11/15", "open": 17.16, "high": 17.44, "low": 17.13, "close": 17.31, "volume": 268504 }, 
    { "date": "05/12/15", "open": 17.28, "high": 17.44, "low": 16.99, "close": 17.24, "volume": 376961 }, 
    { "date": "05/13/15", "open": 17.24, "high": 17.3, "low": 17.06, "close": 17.2, "volume": 244617 }, 
    { "date": "05/14/15", "open": 17.24, "high": 17.25, "low": 17.02, "close": 17.08, "volume": 252526 }, 
    { "date": "05/15/15", "open": 17.06, "high": 17.16, "low": 16.95, "close": 16.95, "volume": 274783 }, 
    { "date": "05/18/15", "open": 16.95, "high": 17.01, "low": 16.76, "close": 16.87, "volume": 418513 }, 
    { "date": "05/19/15", "open": 16.93, "high": 16.94, "low": 16.6, "close": 16.83, "volume": 367660 }, 
    { "date": "05/20/15", "open": 16.8, "high": 16.9, "low": 16.65, "close": 16.86, "volume": 297914 }, 
    { "date": "05/21/15", "open": 16.9, "high": 17.08, "low": 16.79, "close": 16.88, "volume": 229346 }, 
    { "date": "05/22/15", "open": 16.9, "high": 17.05, "low": 16.85, "close": 17, "volume": 253279 }, 
    { "date": "05/26/15", "open": 17.03, "high": 17.08, "low": 16.86, "close": 17.01, "volume": 212640 }, 
    { "date": "05/27/15", "open": 17.01, "high": 17.99, "low": 16.87, "close": 17.75, "volume": 857109 }, 
    { "date": "05/28/15", "open": 17.77, "high": 17.77, "low": 17.44, "close": 17.62, "volume": 338482 }
            ]

Make sure to add the following references in code view:

System.Collections.Generic
System.Windows
System.Runtime.Serialization

Visual Basic
C#

Visual Basic

<DataContract>
Public Class Quote
    <DataMember(Name:="date")>
    Public Property [Date]() As String
        Get
            Return m_Date
        End Get
        Set
            m_Date = Value
        End Set
    End Property
    Private m_Date As String

    <DataMember(Name:="high")>
    Public Property High() As Double
        Get
            Return m_High
        End Get
        Set
            m_High = Value
        End Set
    End Property
    Private m_High As Double

    <DataMember(Name:="low")>
    Public Property Low() As Double
        Get
            Return m_Low
        End Get
        Set
            m_Low = Value
        End Set
    End Property
    Private m_Low As Double

    <DataMember(Name:="open")>
    Public Property Open() As Double
        Get
            Return m_Open
        End Get
        Set
            m_Open = Value
        End Set
    End Property
    Private m_Open As Double

    <DataMember(Name:="close")>
    Public Property Close() As Double
        Get
            Return m_Close
        End Get
        Set
            m_Close = Value
        End Set
    End Property
    Private m_Close As Double

    <DataMember(Name:="volume")>
    Public Property Volume() As Double
        Get
            Return m_Volume
        End Get
        Set
            m_Volume = Value
        End Set
    End Property
    Private m_Volume As Double
End Class
''' Interaction logic for MWBollinger.xaml
Partial Public Class MWBollinger
    Inherits Window
    Private dataService As DataService = DataService.GetService()
    Public Sub New()
        InitializeComponent()
    End Sub
    Public ReadOnly Property Data() As List(Of Quote)
        Get
            Return dataService.GetData()
        End Get
    End Property
End Class

    [DataContract]
    public class Quote
    {
        [DataMember(Name = "date")]
        public string Date { get; set; }

        [DataMember(Name = "high")]
        public double High { get; set; }

        [DataMember(Name = "low")]
        public double Low { get; set; }

        [DataMember(Name = "open")]
        public double Open { get; set; }

        [DataMember(Name = "close")]
        public double Close { get; set; }

        [DataMember(Name = "volume")]
        public double Volume { get; set; }
    }
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        DataService dataService = DataService.GetService();
        public MainWindow()
        {
            InitializeComponent();
        }
        public List<Quote> Data
        {
            get
            {
                return dataService.GetData();
            }
        }        
    }
}