Data binding collection

[lenin]

Hi,
I have a slight issue with binding data using the binding collection. I have a project consisting of a class def. and some client code. Basically the class attaches to and returns records from a database, and binds a field to a simple text box.

This works fine.

However when I compile the class into a dll, and create a project reusing the original form, and setting the appropriate references, the data returned is not displayed in the the relevant text box.

Points to note.
1. Correct records are definitely returned from the dll
2. The textbox is named correctly in the add method of the new binding collection
3. Source is below.

Any help appreciated.

Thanks in advance.


Class:
======

'//=================================================================================================
'//=================================================================================================
'//
'// Tony Hamill
'// Data Aware Class to scroll through recordset and automtically update records
'// on the fly.
'//
'//==================================================================================================
'//==================================================================================================



'//===================================================================================================
'//===================================================================================================
'// Module Level Statments
'//===================================================================================================
'//===================================================================================================

Option Explicit

Private rs As ADODB.Recordset
Private lb_changed As Boolean
' Invoke WithEvents to Confirm Connection was successful
Private WithEvents cn As ADODB.Connection


'//===================================================================================================
'//===================================================================================================
'// Compiler Constants
'//===================================================================================================
'//===================================================================================================


'//===================================================================================================
'//===================================================================================================
'// DLL Imports
'//===================================================================================================
'//===================================================================================================


'//===================================================================================================
'//===================================================================================================
'// Constants
'//===================================================================================================
'//===================================================================================================

'//===================================================================================================
'//===================================================================================================
'// Enumerated Data Types
'//===================================================================================================
'//===================================================================================================



Private Sub Class_GetDataMember(DataMember As String, Data As Object)

'//===================================================================================================
'//===================================================================================================
'//
'// The GetDataMember event is available only when an object’s DataSourceBehavior
'// property is set to vbDataSource or vbOLEDBProvider (for classes only). You can
'// add code to the GetDataMember event procedure to initialize a data member or to
'// select from multiple data members within an object.
'//
'//===================================================================================================
'//===================================================================================================

Set Data = rs
End Sub

Private Sub Class_Initialize()
'//===================================================================================================
'// Initialise all the relevant connection, recordset values
'//===================================================================================================

Dim ls_cn As String
Dim ls_SQL As String

' set no change of text box
lb_changed = False


ls_SQL = "Select * from query_status"
ls_cn = "DSN=Class"

Set cn = New ADODB.Connection
Set rs = New ADODB.Recordset

cn.Open ls_cn
' rs.CursorLocation = adUseClient
rs.Open ls_SQL, ls_cn, adOpenStatic, adLockOptimistic
MsgBox "Class Initialised"
MsgBox rs.RecordCount


End Sub

Public Sub MoveForward()

rs.MoveNext
If rs.EOF Then
rs.MoveFirst
End If
MsgBox rs!querystatus
End Sub

Public Sub MoveBack()
rs.MovePrevious
If rs.BOF Then
rs.MoveLast
End If
MsgBox rs!querystatus
End Sub

Private Sub cn_ConnectComplete(ByVal pError As ADODB.Error, adStatus As ADODB.EventStatusEnum, ByVal pConnection As ADODB.Connection)
' MsgBox "Connected Succesfully", , "SQL Connection OK"
End Sub

Public Sub Check_For_Update(newValue As String)

'//===========================================================
'//
'// Check if text field has changed
'//
'//===========================================================

If lb_changed Then
rs!querystatus = newValue
rs.Update
End If

lb_changed = False

End Sub

Public Sub Text_Changed()
'//===================================================================================================
'// Set private member if text box has changed
'//===================================================================================================

lb_changed = True
End Sub



Client - Form
==============

Private objSource As navigation
Private objBindingCollection As BindingCollection

Private Sub Form_Load()

Set objSource = New navigation
Set objBindingCollection = New BindingCollection


' Assign the source class to the Binding
' Collection’s DataSource property.
Set objBindingCollection.DataSource = objSource
' Add a binding to the Collection.
objBindingCollection.Add txtConsumer, "Text", "queryStatus"
End Sub

Private Sub sBtnBack_Click()
objSource.Check_For_Update (txtConsumer.Text)
objSource.MoveBack
End Sub

Private Sub sBtnForward_Click()
objSource.Check_For_Update (txtConsumer.Text)
objSource.MoveForward
End Sub


Private Sub txtConsumer_KeyDown(KeyCode As Integer, Shift As Integer)

' Ability to use navigation keys
If KeyCode = 39 Then
objSource.MoveForward
ElseIf KeyCode = 37 Then
objSource.MoveBack
End If
End Sub

Private Sub txtConsumer_KeyPress(KeyAscii As Integer)
objSource.Text_Changed
End Sub

[kingd9]

Have you tried adding you dll class project to you client project and then referencing it. This way you can step into the class code and then you can use the immediate window to see what the current record is. I was just playing around with the example in the MSDN and I got it to work as a dll.
Hope this helps

[soesau]

Try to refresh the data binding properties of your text boxes and other object at run time.

i.e. txtSample.DataSource = "c:\.....
txtSample.DataField = "Name"

I believe this should refresh the connection.

[lenin]

Soesau,
I'm not sure what you mean. when using the databinding collection there is no need to set things like datamember, datafield etc. I sthis what you meant?

Lenin