HOWTO: Dynamically Create Excel 5.0 Charts in OLE 2.0 Control

Last reviewed: September 30, 1997
Article ID: Q147803
The information in this article applies to:

- Standard, Professional and Enterprise Editions of Microsoft Visual

  Basic, 16-bit, for Windows, version 4.0
- Microsoft Excel for Windows, version 5.0

SUMMARY

This article demonstrates how to create new Excel 5.0 charts at run-time to be displayed in the Visual Basic OLE 2.0 container control.

MORE INFORMATION

The Visual Basic OLE container control can be used to embed new OLE objects at run-time. One of the objects that you can embed is an Excel chart. It is basically a four-step process:

  1. To embed a new chart into the OLE control, set the Class property to Excel.Chart or Excel.Chart.5. Both classes (Excel.Chart and Excel.Chart.5) are for Excel charts. But Excel.Chart.5 is version dependent; it specifies an Excel version 5.0 chart object.

  2. Create the object by setting the Action property to OLE_CREATE_EMBED. This embeds a default chart (Chart1) from Excel into the OLE control. The chart (Chart1) is part of a default workbook (Book1) that also contains a default worksheet (Sheet1) to provide data for the chart.

  3. Set object variables to reference the Excel objects you need to manipulate the chart through OLE Automation. This will make your code smaller and easier to understand.

  4. Call the ChartWizard Method to format the chart.

Setting Object Variables to Reference Excel Objects

The OLE control provides the Object property to allow you to refer to the object you created. For example, the following code creates and embeds a chart into the OLE control and then sets the title:

   Const OLE_CREATE_EMBED = 0
   Ole1.Class = "Excel.Chart.5"
   Ole1.Action = OLE_CREATE_EMBED
   Ole1.Object.HasTitle = 1
   Ole1.Object.ChartTitle.Caption = "Expenses"

You could navigate from the Object property all the time, but it would be cumbersome. To make it easier, you can set object variables to reference the objects you want. Here is a modified version of the previous example with object variables:

   Const OLE_CREATE_EMBED = 0
   Dim objChart as Object
   Dim objChartTitle as Object
   Ole1.Class = "Excel.Chart.5"
   Ole1.Action = OLE_CREATE_EMBED
   Set objChart = Ole1.Object
   Set objChartTitle = Ole1.Object.ChartTitle
   objChart.HasTitle = 1
   objChartTitle.Caption = "Expenses"

The example shown at the end of this article uses three object variables:
  • One referring to the chart.
  • One referring to the worksheet.
  • One referring to the application object.

Calling the ChartWizard Method to Format a Chart

To format a chart quickly, Excel provides the ChartWizard method. With one call to the ChartWizard method, you can create a chart in one of many predefined formats. The example uses this method, but you could also use direct object manipulation of the chart.

Before you can call the ChartWizard method, the worksheet needs to be filled with the proper data. The example creates random data. Most of the time you will be using more meaningful data that you can manipulate with Excel. In the example, the xlRows orientation is used with 1 row for category labels and one column for series labels. Here is a diagram showing how the data is put into the worksheet:

|                | Category 1 Label | Category 2 Label |
| Series 1 Label | Data Value       | Data Value       |
| Series 2 Label | Data Value       | Data Value       |
 -----------------------------------------------------------
|                |                  |                  |

Once the data (including labels) has been added to the worksheet, you pass the entire range to the ChartWizard method along with the other formatting parameters.

ChartWizard Syntax, Parameters, and Descriptions

SYNTAX:

Object.ChartWizard(Source, Gallery, Format, PlotBy, CategoryLabels, SeriesLabels, HasLegend, Title, CategoryTitle, ValueTitle, ExtraTitle)

Parameter       Description

Object          The Chart object.
Source          Specifies range that contains source data for the chart.
Gallery         Specifies chart type (see constants in example.)
Format          Specifies built-in autoformat.
PlotBy          Specifies orientation of the data (xlRows or xlColumns.)
CategoryLabels The number of rows or columns containing category labels.
SeriesLabels    The number of rows or columns containing series labels.
HasLegend       Specifies if chart has a legend.
Title           The title text of the chart.
CategoryTitle   Category axis title text.
ValueTitle      Value axis title text.
ExtraTitle      Additional axis title text for some charts.

The parameters that are most important to the ChartWizard method are:
  • PlotBy
  • CategoryLabels
  • SeriesLabels

These parameters either determine how your data is going to be set up, or they are initialized to fit the data you have.

To determine the Gallery and Format parameters, you may want to modify the example. Also, you could record the use of the ChartWizard in Excel and see what parameters are used.

All that is left after calling the ChartWizard method is closing the application and object references.

Step-by-Step Example

  1. Start a new project in Visual Basic. Form1 is created by default.

  2. Add an OLE 2.0 control to Form1, and choose the Cancel button on the Insert Object dialog.

  3. Add a CommandButton (Command1) to Form1.

  4. Put the following code in the CommandButton click event.

          Private Sub cmdPrint_Click()
    
              Me.PrintForm
          End Sub
    
             Private Sub cmdQ147803_Click()
    
                ' Excel chart constants (ODK 1.0 XLCONST.BAS or MsgBox
                ' in Excel):
                Const xlArea = 1
                Const xlBar = 2
                Const xlColumn = 3
                Const xlLine = 4
                Const xlPie = 5
                Const xlRadar = -4151
                Const xlXYScatter = -4169
                Const xlCombination = -4111
                Const xl3DArea = -4098
                Const xl3DBar = -4099
                Const xl3DColumn = -4100
                Const xl3DLine = -4101
                Const xl3DPie = -4102
                Const xl3DSurface = -4103
                Const xlDoughnut = -4120
    
                ' Excel orientation constants:
                Const xlRows = 1
                Const xlColumns = 2
    
                Dim objChart As Object           'Object reference to Excel
                                                 'Chart
                Dim objXL As Object              'Object reference for Excel
                                                  App
                Dim objSheet As Object           'Object reference to Excel
                                                 'Worksheet
                Dim iRow As Integer              'Index variable for the
                                                 'current Row
                Dim iCol As Integer              'Index variable for the
                                                 'current Row
                Dim cRows As Integer             'Number of rows
                Dim cCols As Integer             'Number of Columns
                Dim cwSource As String           'Named Range
                Static cwGallery(15) As Integer  'Array for Chart types
                Static iGallery As Integer       'Index for Chart type array
                Dim cwFormat As Integer          'Format of Chart type
                Dim cwPlotBy As Integer          'How data is taken from
                                                 'Worksheet
                Dim cwCategoryLabels As Integer  'Rows/Cols with Catagory
                                                 'labels
                Dim cwSeriesLabels As Integer    'Rows/Cols with Catagory
                                                 'Labels
                Dim cwHasLegend As Integer       'Display Legend
                Dim cwTitle As String            'Chart Title
                Dim cwCategoryTitle As String    'Category Title
                Dim cwValueTitle As String       'Value Title
                Dim cwExtraTitle As String       'Extra Title for some Charts
                                                 'disable this button
                cmdQ147803.Enabled = False
                ' Fill in array with possible Chart types:
                cwGallery(1) = xlArea
                cwGallery(2) = xlBar
                cwGallery(3) = xlColumn
                cwGallery(4) = xlLine
                cwGallery(5) = xlPie
                cwGallery(6) = xlRadar
                cwGallery(7) = xlXYScatter
                cwGallery(8) = xlCombination
                cwGallery(9) = xl3DArea
                cwGallery(10) = xl3DBar
                cwGallery(11) = xl3DColumn
                cwGallery(12) = xl3DLine
                cwGallery(13) = xl3DPie
                cwGallery(14) = xl3DSurface
                cwGallery(15) = xlDoughnut
    
                ' Embed a new Excel 5.0 Chart into the OLE control:
                OLE1.CreateEmbed "", "Excel.Chart.5"
                'BEGIN FIX FOR DIFFERING OBJECT MODELS BETWEEN VERSIONS 7 & 8
                ' Set object references to Chart, Worksheet, and Application
                'objects:
                If Left(OLE1.object.Application.Version, 1) = "7" Then
                'Excel 95's object model is different from Excel 97's
                  Set objChart = OLE1.object ' Chart1 default chart
                Else  'assume all future excel object models are going to be
                      'the same
                Set objChart = OLE1.object.ActiveChart 'ole1.object is in
                                                       'Excel 97 the workbook
                End If
                Set objSheet = objChart.Parent.Worksheets(1) ' Sheet1 default
                                                             ' data
    
                Set objXL = objChart.Application
                'END FIX
                ' Set the number of columns and rows used for data:
                cCols = 10
                cRows = 3
    
                ' Create Series Labels on Worksheet:
                For iRow = 1 To cRows
                   objSheet.Cells(iRow + 1, 1).Value = "SL" & iRow
                Next
    
                ' Create Category Labels on Worksheet:
                For iCol = 1 To cCols
                   objSheet.Cells(1, iCol + 1).Value = "CL" & iCol
                Next
                'exiting here leaves the default chart drawn with sample data
                ' Create random data on Worksheet:
                Randomize Timer
                For iRow = 1 To cRows
                   For iCol = 1 To cCols
                      objSheet.Cells(iRow + 1, iCol + 1).Value = _
                   Int(Rnd * 50) + 1
                Next iCol
                Next iRow
    
                ' Name the Range containing the previously added data:
                objSheet.Range(objSheet.Cells(1, 1), objSheet.Cells(cRows + _
                1, cCols + 1)).Name = "ChartDataRange"
                'objSheet.Range(objSheet.Cells(1, 1), objSheet.Cells(cRows + _
                1, cCols + 1)).Clear
                ' Set the ChartWizard parameters:
                cwSource = "ChartDataRange"       'Name of Named Range
                iGallery = iGallery Mod 15 + 1    'Iterate through 15 Chart
                                                  'types
                cwFormat = 1                      'Use default format of Chart
                                                  'Type
                cwPlotBy = xlRows                 'Rows = Series orientation
                cwCategoryLabels = 1              '1 Row contains Category
                                                  'Labels
                cwSeriesLabels = 1                '1 Column contains Series
                                                  'Labels
                cwHasLegend = 1                   'Display the Legend
                cwTitle = "Embedded Chart"        'Chart Title
                cwCategoryTitle = "Categories"    'Category Title
                cwValueTitle = "Values"           'Value Title
                cwExtraTitle = "Extras"           'Extra Title
    
                ' Use the ChartWizard method to fill in the Chart:
                objChart.ChartWizard cwSource, cwGallery(iGallery), cwFormat,
                cwPlotBy, cwCategoryLabels, cwSeriesLabels, cwHasLegend,
                cwTitle,cwCategoryTitle, cwValueTitle, cwExtraTitle
                ' Shut Down Excel and erase objects:
                Set objXL = Nothing
                Set objChart = Nothing
                Set objSheet = Nothing
                'enable this button
                cmdQ147803.Enabled = True
             End Sub
    
          Private Sub cmdXLView_Click()
                OLE1.DoVerb vbOLEOpen
          End Sub
    
    

  5. Save the project.

  6. Run the program, and click the Command1 button. The first chart should be created.

  7. Keep clicking the Command1 button to cycle through the 15 Gallery chart types of Format 1.

Notes

  • To modify a chart in the OLE control, you must activate the control by first setting the Verb property to -1 (Edit) and then setting the Action property to 7 (OLE_ACTIVATE). Then the Object property will refer to an active object.
  • The example uses Format 1 with the ChartWizard method. You may want to experiment with other values.
  • After using the ChartWizard method, you can still use objects, methods, and properties of the Chart object to modify it.
  • Users will be able to edit the chart by double-clicking the OLE control or by clicking the right mouse button and choosing Edit from the pop-up menu. You can eliminate this ability by setting the AutoActivate and AutoVerbMenu properties of the OLE control.
Keywords          : IAPOLE vb416 VB4WIN vbwin GnrlVb kbprg kbtool
Technology        : kbole kbvba
Version           : WINDOWS:4.0
Platform          : WINDOWS
Issue type        : kbhowto


================================================================================


THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Last reviewed: September 30, 1997
© 1998 Microsoft Corporation. All rights reserved. Terms of Use.