PIE CHART OBJECT AND VBA

Introduction.

This is the continuation of a discussion on working with Chart Object in VBA. We have created a small Table and a Report with a Chart Object on it, in the earlier Post Working with Chart Object in VBA and going through a few simple Property changes in the Chart Object to get prepared for the Demo of the VBA Programs. Please go through Steps 1 to 7 explained in the earliest Post, by following the link above, and continue.

You may have a look at the Column Chart and VBA topic at your convenience as well.

PIE Chart Options.

If you have already tried out the Code given in the earlier Posts then you are familiar with most of the Code Segments that you see here and will have no difficulty understanding them. The difference is only in the formatting method of individual PIE Slices and a few property changes also. In this example, we will try three types of Pie Charts: 1. 3D Pie, 2. 3D Pie Exploded, 3. Pie of Pie.

1. Copy and Paste the code given below into a Global Module in your Database.

   Public Function PieChart(ByVal ReportName As String, ByVal ChartObjectName As String)
   '---------------------------------------------------
   'Author : a.p.r. pillai
   'URL    : http://www.msaccesstips.com
   'Date   : July-2008
   'Customized Source Code : from Microsoft Access Help
   '---------------------------------------------------
   Dim Rpt As Report, grphChart As Object
   Dim msg As String, lngType As Long, cr As String
   Dim ctype As String, typ As Integer, j As Integer
   Dim db As Database, rst As Recordset, recSource As String
   Dim colmCount As Integer, chartType(1 To 5) As String
   Const twips As Long = 1440
   
   On Error GoTo PieChartChart_Err
   
   chartType(1) = "3D Pie Chart"
   chartType(2) = "3D Pie Exploded"
   chartType(3) = "Pie of Pie"
   chartType(4) = "Quit"
   chartType(5) = "Select 1-4, 5 to Cancel"
   
   cr = vbCr & vbCr
   msg = ""
   For j = 1 To 5
     msg = msg & j & ". " & chartType(j) & cr
   Next
   
   ctype = "": typ = 0
   Do While typ < 1 Or typ > 4
    ctype = InputBox(msg, "Select Chart Type")
    If Len(ctype) = 0 Then
       typ = 0
    Else
       typ = Val(ctype)
    End If
   Loop
   
   Select Case typ
       Case 4
           Exit Function
       Case 1
          lngType = xl3DPie
       Case 2
          lngType = xl3DPieExploded
       Case 3
          lngType = xlPieOfPie
   End Select
   
   DoCmd.OpenReport ReportName, acViewDesign
   Set Rpt = Reports(ReportName)
   
   Set grphChart = Rpt(ChartObjectName)
   
   grphChart.RowSourceType = "Table/Query"
   recSource = grphChart.RowSource
   
   If Len(recSource) = 0 Then
      MsgBox "RowSource value not set, aborted."
      Exit Function
   End If
   
   'get number of columns in chart table/Query
   'if Table or SQL string is not valid then
   'generate error and exit program
   Set db = CurrentDb
   Set rst = db.OpenRecordset(recSource)
   colmCount = rst.Fields.Count
   rst.Close
   
   're-size the Chart
   With grphChart
       .ColumnCount = colmCount
       .SizeMode = 3
       .Left = 0.2917 * twips
       .Top = 0.2708 * twips
       .Width = 5 * twips
       .Height = 4 * twips
   End With
   
   'activate the chart for modification.
   grphChart.Activate
   
   'Chart type, Title, Legend, Datalabels,Data Table
   With grphChart
        .chartType = lngType
       .HasLegend = True
       .HasTitle = True
       .ChartTitle.Font.Name = "Verdana"
       .ChartTitle.Font.Size = 14
       .ChartTitle.Text = chartType(typ) & " Chart."
       .HasDataTable = False
   End With
   
   'format Pie slices with gradient color
   With grphChart.SeriesCollection(1)
       .HasDataLabels = True
       .DataLabels.Position = xlLabelPositionBestFit
       .HasLeaderLines = True
       .Border.ColorIndex = 19 'edges of pie shows in white color
       For j = 1 To .Points.Count
           With .Points(j)
               .Fill.ForeColor.SchemeColor = Int(Rnd(Timer()) * 54) + 2
               .Fill.OneColorGradient msoGradientVertical, 4, 0.231372549019608
               .DataLabel.Font.Name = "Arial"
               .DataLabel.Font.Size = 10
               .DataLabel.ShowLegendKey = False
               '.ApplyDataLabels xlDataLabelsShowValue
               .ApplyDataLabels xlDataLabelsShowLabelAndPercent
           End With
       Next
   End With
   
   'Chart Area Border
   With grphChart
       .ChartArea.Border.LineStyle = xlDash
       .PlotArea.Border.LineStyle = xlDot
       .Legend.Font.Size = 10
   End With
   
   'Chart Area Fill with Gradient Color
   With grphChart.ChartArea.Fill
       .Visible = True
       .ForeColor.SchemeColor = 17
       .BackColor.SchemeColor = 2
       .TwoColorGradient msoGradientHorizontal, 2
   End With
   
   'Plot Area fill with Gradient Color
   With grphChart.PlotArea.Fill
       .Visible = True
       .ForeColor.SchemeColor = 6
       .BackColor.SchemeColor = 19
       .TwoColorGradient msoGradientHorizontal, 1
   End With
   
   grphChart.Deselect
   
   DoCmd.Close acReport, ReportName, acSaveYes
   DoCmd.OpenReport ReportName, acViewPreview
   
   PieChart_Exit:
   Exit Function
   
   PieChart_Err:
   MsgBox Err.Description, , "PieChart()"
   Resume PieChart_Exit
   End Function
   

2. Press Ctrl+G to display the Debug Window (Immediate Window) in the VBA Editing View, type the following command in the Debug Window, and press Enter:

PieChart "MyReport1", "Chart1"

Sample run: an image of Option-1:

Sample run: an image of Option-2:

Sample run: an image of Option-3:

Run it from the Command Button Click.

If you prefer to run this command from the On_Click() Event Procedure of a Command Button on your Form, you may do so. The Program will open myReport1 in Design View, resize the Chart1 Chart Object, big enough for Printing or Viewing, and format the Chart elements. The Program saves the Report and re-opens it in Print Preview.

The Analysis of Values appearing in a PIE Chart is done differently than in other forms of Charts. That is why PIE Charts take only one set of Values.

If, four of us join together and decided to buy a Cake worth $100 and each one of us takes a share of the Cost of $6 (I will take the first share amount if no icing), $60, $20 and $14, the claim on the Cake is in relation to the share of Amount. The Pie Slices will show the size of each one of our shares.

In the earlier examples, the Formatting of all the Bars of a particular Data Series is applied together as a single collection of Objects with higher-level reference grphChart.SeriesCollection(). But in Pie Chart, individual elements of a Data Series (Pie Slices) are referenced by getting one step further deep into the collection of Objects as grphChart.SeriesCollection().Points() and formats them separately with different sets of Gradient Colors.

Tips: If you would like to format individual Bars of a Bar Chart you can use this method. But you must remove the following Properties from the Code, used for PIE Chart:

.DataLabels.Position = xlLabelPositionBestFit
.HasLeaderLines = True
.Border.ColorIndex = 19 'showing edges of Pie slices with white color
.ApplyDataLabels xlDataLabelsShowLabelAndPercent

Chart Formatting.

The X-Axis and Y-Axis Titles are not used in Pie Charts and these Code segments are removed from the Program. Chart Area and Plot Area are formatted with a different set of light Colors, different from our earlier examples. With these elements also we can use the Rnd() Function to generate different sets of values in each Run, formatting with Gradient Color. But, it may not come up with the correct color combination every time, good enough for viewing or Printing. If you do not like the current Scheme of  Color Values you may try out different Color Values from the Color Chart given on the first Post Working with Chart Object in VBA.

Download the Demo Database.

Download Demo Database

1. MS-Access and Graph Charts
2. MS-Access and Graph Charts-2
3. Working With Chart Object in VBA
4. Column Chart and VBA
5. Pie Chart Object and VBA
6. Missing Lines in Line-Chart
7. Pie Chart and Live Data on Form
8. Scaling Chart Object
9. Cross-Tab Union Queries for Chart