Q305985: HOWTO: Add Functionality to Your Dynamically Built Grid

Article: Q305985
Product(s): Microsoft FoxPro
Version(s): 3.0,3.0b,5.0,5.0a,6.0,7.0
Operating System(s): 
Keyword(s): kbContainer kbCtrl kbvfp kbvfp300b kbvfp500 kbvfp500a kbvfp600 kbGrpDSFox kbDSupport kb
Last Modified: 30-AUG-2001

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 5.0a, 6.0, 7.0 
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SUMMARY
=======

Although a grid has its own events, the events do not always fire when you would
expect them to. Because a grid is a container control, the objects in the
container receive the events. Therefore, to add functionality to a grid, you
must add the method code to the text boxes (or other controls) that display the
data. However, you cannot add code to objects at run time.

MORE INFORMATION
================

Because you cannot add code to objects at run time, you must use a custom class
for your text boxes. The grid, however, does its best to display the table as if
you were browsing it, so you need to be careful about the order in which you do
things. You can also add code to custom header classes; for example, code to
sort the grid by the column that you click.

The following code displays a message box when you double-click the displayed
data. If you double-click below or to the right of the data, the grid DblClick
event fires instead.

  PUBLIC loForm

  CD HOME() 

  *!* Make sure that the grid doesn't pick this up automatically
  USE labels IN 1
  SELECT 25  && Temporally select blank work area.

  loForm = CREATEOBJECT("Form")
  loForm.AddObject("grdLabels", "grdName")

  WITH loForm.grdLabels
     .AddObject("colName", "Column")
     *!* We now have a Grid with a single column containing a header
     *!* and a textbox.
     
     .colName.Width = 200

     *!* If this is set before the columns are defined, the
     *!* grid picks up the columns it thinks it needs.
     .RecordSourceType = 1
     .RecordSource = "labels"
     
     .colName.ControlSource = "labels.name"
     .colName.Header1.Caption = "Label name"

     *!* Now we add our custom textbox control, and remove the original.
     .colName.AddObject("txtName", "txtGrid")
     .colName.txtName.BorderStyle = 0
     .colName.CurrentControl = "txtName"
     .colName.RemoveObject("Text1")

     *!* The default visibility for all objects added with AddObject is .F.
     .colName.Visible = .T.
     .Visible = .T.
  ENDWITH

  loForm.Visible = .T.

  DEFINE CLASS txtGrid AS TextBox
     PROCEDURE DblClick
        =MESSAGEBOX(STR(RECNO()))
     ENDPROC
  ENDDEFINE

  DEFINE CLASS grdName AS Grid
     PROCEDURE DblClick
        =MESSAGEBOX("You didn't click on the data.")
     ENDPROC
  ENDDEFINE

REFERENCES
==========

For additional information about grids and their events, click the article
number below to view the article in the Microsoft Knowledge Base:

  Q128075 PRB: Grid Does Not Respond to the Click or DblClick Events

Additional query words:

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Keywords          : kbContainer kbCtrl kbvfp kbvfp300b kbvfp500 kbvfp500a kbvfp600 kbGrpDSFox kbDSupport kbCodeSnippet kbvfp300xSearch kbvfp500xSearch kbvfp700 
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b kbVFP500 kbVFP600 kbVFP700 kbVFP500a
Version           : :3.0,3.0b,5.0,5.0a,6.0,7.0
Issue type        : kbhowto

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