PRB: DataBound Controls Not Updated with DataEnvironment Using Refresh Method

• Microsoft Visual Basic Enterprise Edition for Windows, version 6.0

SYMPTOMS

The DataCombo and DataGrid controls are not refreshed when using the Refresh method. This behavior is exhibited when using the DataEnvironment.

RESOLUTION

There are several workarounds. One is to use the ADO Data Control instead of the DataEnvironment. Another is to rebind the controls to the DataEnvironment.

The following code rebinds the controls. Replace the code in the Refresh Click event in the Steps to Reproduce Behavior section with the following:

Set DataGrid1.DataSource = DataEnvironment1
Set DataCombo1.DataSource = DataEnvironment1
Set DataCombo1.RowSource = DataEnvironment1 

STATUS

This behavior is by design.

MORE INFORMATION

When running an application and then adding or updating data, the user may want to see the changes reflected in the DataCombo. However, when using the DataEnvironment, these changes are not seen without re-binding the control.

Steps to Reproduce Behavior

1. Create a Standard EXE Project in Visual Basic. Form1 is created by default.



2. From the Project menu, select Add Data Environment.



3. Alternate-click Connection1 and choose Properties. Select Microsoft Jet 3.51 OLE DB Provider, click Next, and choose the Nwind.mdb database. Click OK.



4. Alternate-click Connection1, and select Add Command. Next, alternate-click Command1 and select Properties. In the Database Object drop-down box, select Table, and, under Object name, select Customers. Click OK and the DataEnvironment is created.



5. From the Project/Components menu, add the Microsoft DataGrid Control 6.0 and the Microsoft DataList Controls 6.0.



6. On Form1, place a DataCombo control, a DataGrid control, and a Command Button. Rename the command button Refresh.



7. Set the DataSource and RowSource properties of the DataCombo to DataEnvironment1. Set the RowMember to Command1, and ListField property to CustomerID.



8. Set the DataGrid Datasource to DataEnvironment1 and the DataMember to Command1. In the Refresh command button Click event, place the following code:




' Updates the recordset with the added data.
  DataEnvironment1.rscommand1.Requery

' Supposed to Refresh new data in the Datagrid
  DataGrid1.Refresh

' Should have updated the Combobox with the new data
  DataCombo1.ReFill
  DataCombo1.Refresh 

9. Press the F5 key to run the code and look at the data in both the DataGrid and DataCombo. Pause the code and open the Nwind.mdb Customers table in Access and add a new CustomerID "ZZZZZ." Close the table and resume running the application in Visual Basic. Click the Refresh button to update, and note the DataGrid and the DataCombo do not show the new record.

REFERENCES

For additional information about binding data controls, please see the following article in the Microsoft Knowledge Base:

Q191457 PRB: DataEnvironment Recordset Requery Does Not Refresh Controls

Additional query words:

Keywords          : kbDataBinding kbVBp600 kbDataEnv 
Version           : WINDOWS:6.0
Platform          : WINDOWS 
Issue type        : kbprb 

Last Reviewed: July 20, 1999