VB6 Databinding with the DataGrid (used as a Read-Only RowPicker)

Not much to comment, other than what the Title says.

More common in such scenarios are perhaps MS-HFlexGrids,
but those don't support real DataBinding and are slower, because the
Recordset-Data has to be taken over "as a copy" when a HFlex is used.

The VB6-DataGrid on the other hand, is the only "List-Control" we
have in VB6, which is a true "virtual one" (the Data is kept outside the
Control - in an ADO-Recordset - and then only the visible Rows are rendered).

There's a small "Details-Form" which is shown as a ToolWindow (non-modally),
which then follows the currently clicked Record of the DataGrid in the other Form,
"automagically" due to Binding to the same Recordset (over the Text-Detail-Fields
in the other Form).

Thanks to dilettante for his HFlex-based Demo, where I've stolen the Form-Layout for the ToolForm. :)

The one thing one has to keep in mind, when using a VB6-DataGrid in such a "bound mode" is,
that it behaves with much less "quirks", when it's used in "Batch-Mode" - meaning:
- the ADO-Rs has to use a clientside cursor
- and it should be opened with the Flags: adOpenStatic, adLockBatchOptimistic

With that in place, there's not much it complains about.

The other thing not well-known about the DataGrid is perhaps, how to switch it into
true "Read-Only-Mode" (showing full Row-Selections - and never entering its Edit-Cell-Mode):
- set the Grids "AllowUpdates"-Property to False
- lock the Default-SplitView (at Form_Load-Time) with: DataGrid.Splits(0).Locked = True

Then it will look like in the following ScreenShot:

http://vbRichClient.com/Downloads/DataGridPicker.png

Here's the Demo-Source: Attachment 126275

Have fun.

Olaf

Hi Olaf,

Thanks for this - i´m trying to use it with your sqlite wrapper against a memory db.
This works really fast and i have also managed to update the RS from the grid.
What i do not get to work, is to scroll the grid to the position of eg. a RS.FindNext.
How can this be done?

Quote:

---

Originally Posted by Marko8

Hi Olaf,

Thanks for this - i´m trying to use it with your sqlite wrapper against a memory db.
This works really fast and i have also managed to update the RS from the grid.
What i do not get to work, is to scroll the grid to the position of eg. a RS.FindNext.
How can this be done?

---

The DataSource needs to be manually synchronized after such actions as Rs.FindFirst/Next - e.g.:

Code:

---

Private Sub cmdFind_Click()
  If Rs.FindFirst("ID=" & txtID.Text) Then 'when the ID was found in the cRecordset
    Dim DS As ADODB.Recordset
    Set DS = DG.DataSource
        DS.AbsolutePosition = Rs.AbsolutePosition 'synchronize the Positions manually
  Else
    MsgBox "a Record with ID: " & txtID.Text & " doesn't exist"
  End If
End Sub

---

Here's an example, which demonstrates that (nearly identical to the ADO-based version in the opener-post,
but using SQLite): Attachment 144597

I've also added a new AutoSync-mechanism (for the opposite direction) in new RC5-version 5.0.57,
which ensures that a given Rs.AbsolutePosition will follow along with the actions on its derived DataSource,
so you might want to update to the newest version, if you want to use that.

Olaf

Quote:

---

Originally Posted by Schmidt

I've also added a new AutoSync-mechanism (for the opposite direction) in new RC5-version 5.0.57,
which ensures that a given Rs.AbsolutePosition will follow along with the actions on its derived DataSource,
so you might want to update to the newest version, if you want to use that.
Olaf

---

Thank you, this is very helpful!
With v 57 i get now RS_move events when moving through the datagrid, so i know the current position without silly workarounds.

PS: you forgot to update the website, it still says version 5.0.55