VintaSoft Barcode .NET SDK v10.0
Vintasoft.WpfBarcode Namespace / BarcodeDrawingContextRenderer Class
Members Example




In This Topic
    BarcodeDrawingContextRenderer Class
    In This Topic
    Provides a base abstract class that renders barcode on System.Windows.Media.DrawingContext.
    Object Model
    BarcodeDrawingContextRenderer ClassBarcodeElement Class
    Syntax
    'Declaration
     
    Public MustInherit Class BarcodeDrawingContextRenderer 
       Inherits BarcodeRenderer
    'Usage
     
    Dim instance As BarcodeDrawingContextRenderer
    public abstract class BarcodeDrawingContextRenderer : BarcodeRenderer 
    public __gc abstract class BarcodeDrawingContextRenderer : public BarcodeRenderer 
    public ref class BarcodeDrawingContextRenderer abstract : public BarcodeRenderer 
    Example
    This example shows how to create barcode renderer that overrides standard rendering algorithms.
    ''' <summary>   
    ''' Generate QR barcode as an image.   
    ''' </summary>   
    ''' <param name="value">The value.</param>   
    ''' <param name="width">The image width, in pixels.</param>   
    ''' <param name="height">The image height, in pixels.</param>   
    Public Shared Function GenerateQRBarcodeImage(ByVal value As String, ByVal width As Integer, ByVal height As Integer) As BitmapSource   
        Dim writer As New BarcodeWriter()   
        writer.Settings.Barcode = BarcodeType.QR   
        writer.Settings.Value = value   
        writer.Settings.Resolution = 96.0F   
        writer.Settings.Padding = 0   
        Dim quietZone As Integer = Math.Min(width, height) \ 20   
        writer.Settings.QuietZoneTop = quietZone   
        writer.Settings.QuietZoneLeft = quietZone   
        writer.Settings.QuietZoneRight = quietZone   
        writer.Settings.QuietZoneBottom = quietZone   
        Dim renderer As New BarcodeSimpleRenderer()   
        Return renderer.GetBarcodeAsBitmap(writer, width, height, UnitOfMeasure.Pixels)   
    End Function   
       
    ''' <summary>   
    ''' A simple renderer of matrix barcode.   
    ''' </summary>   
    ''' <remarks>   
    ''' This renderer draws the barcode search patterns and other barcode elements separately.   
    ''' </remarks>   
    Public Class BarcodeSimpleRenderer   
        Inherits BarcodeDrawingContextRenderer   
       
    #Region "Fields"   
       
        ''' <summary>   
        ''' The brush that is used for filling the barcode elements.   
        ''' </summary>   
        Private _barcodeBrush As SolidColorBrush   
       
        ''' <summary>   
        ''' The pen that is used for drawing the barcode elements.   
        ''' </summary>   
        Private _barcodePen As Pen   
       
        ''' <summary>    
        ''' The geometry that is used for drawing the barcode elements.   
        ''' </summary>   
        Private _drawGeometry As GeometryGroup   
       
        ''' <summary>    
        ''' The geometry that is used for filling the barcode elements.   
        ''' </summary>   
        Private _fillGeometry As GeometryGroup   
       
    #End Region   
       
       
       
    #Region "Constructors"   
       
        ''' <summary>   
        ''' Initializes a new instance of the <see cref="BarcodeSimpleRenderer"/> class.   
        ''' </summary>   
        Public Sub New()   
        End Sub   
       
    #End Region   
       
       
       
    #Region "Properties"   
       
        Private _barcodeColor As Color = Colors.Black   
        ''' <summary>   
        ''' Gets or sets the color that is used for drawing the barcode.   
        ''' </summary>   
        Public Property BarcodeColor() As Color   
            Get   
                Return _barcodeColor   
            End Get   
            Set(ByVal value As Color)   
                _barcodeColor = value   
            End Set   
        End Property   
       
    #End Region   
       
       
       
    #Region "Methods"   
       
        ''' <summary>    
        ''' Renders the barcode.   
        ''' </summary>   
        ''' <seealso cref="BarcodeElement" />   
        Public Overrides Sub Render()   
            ' clear groups   
            _fillGeometry = New GeometryGroup()   
            _drawGeometry = New GeometryGroup()   
       
            MyBase.Render()   
       
            ' create brush   
            _barcodeBrush = New SolidColorBrush(BarcodeColor)   
            _barcodeBrush.Freeze()   
       
            ' create pen   
            _barcodePen = New Pen(_barcodeBrush, 1)   
            _barcodePen.LineJoin = PenLineJoin.Round   
            _barcodePen.Freeze()   
       
            ' draw groups   
            _fillGeometry.Freeze()   
            _drawGeometry.Freeze()   
            DrawingContext.DrawGeometry(_barcodeBrush, Nothing, _fillGeometry)   
            DrawingContext.DrawGeometry(Nothing, _barcodePen, _drawGeometry)   
        End Sub   
       
        ''' <summary>   
        ''' Renders the barcode matrix element.   
        ''' </summary>   
        ''' <param name="element">The barcode matrix element to render.</param>   
        ''' <param name="x">The X-coordinate, where barcode matrix element must be rendered.</param>   
        ''' <param name="y">The Y-coordinate, where barcode matrix element must be rendered.</param>   
        Protected Overrides Sub RenderBarcodeMatrixElement(ByVal element As BarcodeMatrixElement, ByVal x As Integer, ByVal y As Integer)   
            ' customize drawing of search patterns   
       
            Dim isAztecSearchPattern As Boolean = False   
            If element Is BarcodeElements.AztecCompactSearchPattern Then   
                isAztecSearchPattern = True   
            ElseIf element Is BarcodeElements.AztecFullRangeSearchPattern Then   
                isAztecSearchPattern = True   
            End If   
       
            ' QR search pattern   
            If element Is BarcodeElements.QrSearchPattern Then   
                ' (x,y)   
                '    #######   
                '    #     #   
                '    # ### #   
                '    # ### #   
                '    # ### #   
                '    #     #   
                '    #######   
                '       (x+7,y+7)                   
                ' draw outer rectangle 7x7   
                _drawGeometry.Children.Add(New RectangleGeometry(New Rect(x + 1.5, y + 1.5, 6, 6)))   
                ' draw inner cell 3x3   
                _fillGeometry.Children.Add(New RectangleGeometry(New Rect(x + 3.75, y + 3.75, 1.5, 1.5)))   
                _drawGeometry.Children.Add(New RectangleGeometry(New Rect(x + 3.5, y + 3.5, 2, 2)))   
                ' Aztec search pattern   
            ElseIf isAztecSearchPattern Then   
                '  Compact/Rune          Full Range   
                '                    (x,y)   
                '                       #############   
                ' (x,y)                 #           #   
                '    #########          # ######### #   
                '    #       #          # #       # #   
                '    # ##### #          # # ##### # #   
                '    # #   # #          # # #   # # #   
                '    # # # # #          # # # # # # #   
                '    # #   # #          # # #   # # #   
                '    # ##### #          # # ##### # #   
                '    #       #          # #       # #   
                '    #########          # ######### #   
                '         (x+9,y+9)     #           #   
                '                       #############   
                '                               (x+13,y+13)   
                ' draw outer rectangles: 13x13, 9x9, 5x5   
                Dim rectCount As Integer   
                If element Is BarcodeElements.AztecFullRangeSearchPattern Then   
                    rectCount = 3   
                Else   
                    rectCount = 2   
                End If   
                For i As Integer = 0 To rectCount - 1   
                    _drawGeometry.Children.Add(New RectangleGeometry(New Rect(x + 0.5, y + 0.5, (rectCount - i) * 4, (rectCount - i) * 4)))   
                    x += 2   
                    y += 2   
                Next   
       
                ' draw inner cell 1x1   
                Dim center As New Point(x + 0.5, y + 0.5)   
                _fillGeometry.Children.Add(New EllipseGeometry(center, 0.5, 0.5))   
                ' DataMatrix and Han Xin Code search patterns   
            ElseIf element.Name.Contains("Search Pattern") Then   
                For yc As Integer = 0 To element.Height - 1   
                    For xc As Integer = 0 To element.Width - 1   
                        If element.Matrix(yc, xc) Is BarcodeElements.BlackCell Then   
                            Dim rect As New Rect(x + xc, y + yc, 1, 1)   
                            Dim rectangle As New RectangleGeometry(rect)   
                            _fillGeometry.Children.Add(rectangle)   
                        End If   
                    Next   
                Next   
            Else   
                MyBase.RenderBarcodeMatrixElement(element, x, y)   
            End If   
        End Sub   
       
        ''' <summary>   
        ''' Renders the barcode element.   
        ''' </summary>   
        ''' <param name="barcodeElement">The barcode element to render.</param>   
        ''' <param name="x">The X-coordinate, where barcode element must be rendered.</param>   
        ''' <param name="y">The Y-coordinate, where barcode element must be rendered.</param>   
        Protected Overrides Sub RenderBarcodeElement(ByVal barcodeElement As BarcodeElement, ByVal x As Integer, ByVal y As Integer)   
            If barcodeElement Is BarcodeElements.BlackCell Then   
                Dim center As New Point(x + 0.5, y + 0.5)   
                _fillGeometry.Children.Add(New EllipseGeometry(center, 0.5, 0.5))   
            Else   
                MyBase.RenderBarcodeElement(barcodeElement, x, y)   
            End If   
        End Sub   
       
        ''' <summary>   
        ''' Returns a <see cref="System.String" /> that represents this instance.   
        ''' </summary>   
        ''' <returns>   
        ''' A <see cref="System.String" /> that represents this instance.   
        ''' </returns>   
        Public Overrides Function ToString() As String   
            Return "Simple dots"   
        End Function   
       
    #End Region   
       
    End Class
    /// <summary>
    /// Generate QR barcode as an image.
    /// </summary>
    /// <param name="value">The value.</param>
    /// <param name="width">The image width, in pixels.</param>
    /// <param name="height">The image height, in pixels.</param>
    public static BitmapSource GenerateQRBarcodeImage(string value, int width, int height)
    {
        BarcodeWriter writer = new BarcodeWriter();
        writer.Settings.Barcode = BarcodeType.QR;
        writer.Settings.Value = value;
        writer.Settings.Resolution = 96f;
        writer.Settings.Padding = 0;
        int quietZone = Math.Min(width, height) / 20;
        writer.Settings.QuietZoneTop = quietZone;
        writer.Settings.QuietZoneLeft = quietZone;
        writer.Settings.QuietZoneRight = quietZone;
        writer.Settings.QuietZoneBottom = quietZone;
        BarcodeSimpleRenderer renderer = new BarcodeSimpleRenderer();
        return renderer.GetBarcodeAsBitmap(writer, width, height, UnitOfMeasure.Pixels);
    }
                
    /// <summary>
    /// A simple renderer of matrix barcode.
    /// </summary>
    /// <remarks>
    /// This renderer draws the barcode search patterns and other barcode elements separately.
    /// </remarks>
    public class BarcodeSimpleRenderer : BarcodeDrawingContextRenderer
    {
                
        #region Fields
                
        /// <summary>
        /// The brush that is used for filling the barcode elements.
        /// </summary>
        SolidColorBrush _barcodeBrush;
                
        /// <summary>
        /// The pen that is used for drawing the barcode elements.
        /// </summary>
        Pen _barcodePen;
                
        /// <summary> 
        /// The geometry that is used for drawing the barcode elements.
        /// </summary>
        GeometryGroup _drawGeometry;
                
        /// <summary> 
        /// The geometry that is used for filling the barcode elements.
        /// </summary>
        GeometryGroup _fillGeometry;
                
        #endregion
                
                
                
        #region Constructors
                
        /// <summary>
        /// Initializes a new instance of the <see cref="BarcodeSimpleRenderer"/> class.
        /// </summary>
        public BarcodeSimpleRenderer()
        {
        }
                
        #endregion
                
                
                
        #region Properties
                
        Color _barcodeColor = Colors.Black;
        /// <summary>
        /// Gets or sets the color that is used for drawing the barcode.
        /// </summary>
        public Color BarcodeColor
        {
            get
            {
                return _barcodeColor;
            }
            set
            {
                _barcodeColor = value;
            }
        }
                
        #endregion
                
                
                
        #region Methods
                
        /// <summary> 
        /// Renders the barcode.
        /// </summary>
        /// <seealso cref="BarcodeElement" />
        public override void Render()
        {
            // clear groups
            _fillGeometry = new GeometryGroup();
            _drawGeometry = new GeometryGroup();
                
            base.Render();
                
            // create brush
            _barcodeBrush = new SolidColorBrush(BarcodeColor);
            _barcodeBrush.Freeze();
                
            // create pen
            _barcodePen = new Pen(_barcodeBrush, 1);
            _barcodePen.LineJoin = PenLineJoin.Round;
            _barcodePen.Freeze();
                
            // draw groups
            _fillGeometry.Freeze();
            _drawGeometry.Freeze();
            DrawingContext.DrawGeometry(_barcodeBrush, null, _fillGeometry);
            DrawingContext.DrawGeometry(null, _barcodePen, _drawGeometry);
        }
                
        /// <summary>
        /// Renders the barcode matrix element.
        /// </summary>
        /// <param name="element">The barcode matrix element to render.</param>
        /// <param name="x">The X-coordinate, where barcode matrix element must be rendered.</param>
        /// <param name="y">The Y-coordinate, where barcode matrix element must be rendered.</param>
        protected override void RenderBarcodeMatrixElement(
            BarcodeMatrixElement element,
            int x,
            int y)
        {
            // customize drawing of search patterns
                
            bool isAztecSearchPattern = false;
            if (element == BarcodeElements.AztecCompactSearchPattern)
                isAztecSearchPattern = true;
            else if (element == BarcodeElements.AztecFullRangeSearchPattern)
                isAztecSearchPattern = true;
                
            // QR search pattern
            if (element == BarcodeElements.QrSearchPattern)
            {
                // (x,y)
                //    #######
                //    #     #
                //    # ### #
                //    # ### #
                //    # ### #
                //    #     #
                //    #######
                //       (x+7,y+7)                
                // draw outer rectangle 7x7
                _drawGeometry.Children.Add(new RectangleGeometry(new Rect(x + 1.5, y + 1.5, 6, 6)));
                // draw inner cell 3x3
                _fillGeometry.Children.Add(new RectangleGeometry(new Rect(x + 3.75, y + 3.75, 1.5, 1.5)));
                _drawGeometry.Children.Add(new RectangleGeometry(new Rect(x + 3.5, y + 3.5, 2, 2)));
            }
            // Aztec search pattern
            else if (isAztecSearchPattern)
            {
                //  Compact/Rune          Full Range
                //                    (x,y)
                //                       #############
                // (x,y)                 #           #
                //    #########          # ######### #
                //    #       #          # #       # #
                //    # ##### #          # # ##### # #
                //    # #   # #          # # #   # # #
                //    # # # # #          # # # # # # #
                //    # #   # #          # # #   # # #
                //    # ##### #          # # ##### # #
                //    #       #          # #       # #
                //    #########          # ######### #
                //         (x+9,y+9)     #           #
                //                       #############
                //                               (x+13,y+13)
                // draw outer rectangles: 13x13, 9x9, 5x5
                int rectCount;
                if (element == BarcodeElements.AztecFullRangeSearchPattern)
                    rectCount = 3;
                else
                    rectCount = 2;
                for (int i = 0; i < rectCount; i++)
                {
                    _drawGeometry.Children.Add(new RectangleGeometry(
                        new Rect(x + 0.5, y + 0.5,
                                (rectCount - i) * 4, (rectCount - i) * 4)));
                    x += 2;
                    y += 2;
                }
                
                // draw inner cell 1x1
                Point center = new Point(x + 0.5, y + 0.5);
                _fillGeometry.Children.Add(new EllipseGeometry(center, 0.5, 0.5));
            }
            // DataMatrix and Han Xin Code search patterns
            else if (element.Name.Contains("Search Pattern"))
            {
                for (int yc = 0; yc < element.Height; yc++)
                {
                    for (int xc = 0; xc < element.Width; xc++)
                    {
                        if (element.Matrix[yc, xc] == BarcodeElements.BlackCell)
                        {
                            Rect rect = new Rect(x + xc, y + yc, 1, 1);
                            RectangleGeometry rectangle = new RectangleGeometry(rect);
                            _fillGeometry.Children.Add(rectangle);
                        }
                    }
                }
            }
            else
            {
                base.RenderBarcodeMatrixElement(element, x, y);
            }
        }
                
        /// <summary>
        /// Renders the barcode element.
        /// </summary>
        /// <param name="barcodeElement">The barcode element to render.</param>
        /// <param name="x">The X-coordinate, where barcode element must be rendered.</param>
        /// <param name="y">The Y-coordinate, where barcode element must be rendered.</param>
        protected override void RenderBarcodeElement(BarcodeElement barcodeElement, int x, int y)
        {
            if (barcodeElement == BarcodeElements.BlackCell)
            {
                Point center = new Point(x + 0.5, y + 0.5);
                _fillGeometry.Children.Add(new EllipseGeometry(center, 0.5, 0.5));
            }
            else
            {
                base.RenderBarcodeElement(barcodeElement, x, y);
            }
        }
                
        /// <summary>
        /// Returns a <see cref="System.String" /> that represents this instance.
        /// </summary>
        /// <returns>
        /// A <see cref="System.String" /> that represents this instance.
        /// </returns>
        public override string ToString()
        {
            return "Simple dots";
        }
                
        #endregion
                
    }
    Inheritance Hierarchy

    System.Object
       Vintasoft.WpfBarcode.BarcodeRenderer
          Vintasoft.WpfBarcode.BarcodeDrawingContextRenderer

    Requirements

    Target Platforms: Windows 8, Windows 7, Windows Vista, Windows XP, Windows Server 2012, Windows Server 2008, Windows Server 2003

    See Also