Data Binding to Textbox

[Peter]

Hi,

I'm trying to create a form that shows table rows in a listbox. Several
comboboxes expand the foreign key fields into text values from the parent
tables, and there are also some textboxes for the non-foreign key fields.
When the user clicks on a row in the listbox, the comboboxes' SelectedItem
changes to reflect the foreign key selections in the currently selected row.
That part is working fine. I also want the textboxes to change to reflect
the currently selected item's values.

I created a DataBinding in the textbox (actually, it's a custom control,
NumericTextBox, which only allows numeric values). The field that is bound
to the NumericTextBox is of type int. The property it is bound to (IntValue)
is of type Int32 (although I've tried many different types with no luck).
I've also tried using a plain textbox to no avail.

The problem is that, initially, the NumericTextBox displays the correct
value for the initially selected row. But if I enter that text box, I can't
leave it. And if I change the value of it, when I press tab, it changes back
to what it was. Also, if (before clicking it) I change to a different row in
the listbox, all the comboboxes update, but the textbox does not. What's
going on?

***
Private Sub PaperEditor_Loa d(ByVal sender As Object, ByVal e As
System.EventArg s) Handles MyBase.Load
'Initialize data binding for listbox.
lbPaperSelector .DataSource = internalDataSet .Paper 'The main paper
table, with foreign keys galore.
lbPaperSelector .DisplayMember = "FullText"
lbPaperSelector .ValueMember = "ID"

'Set selected item to the first paper listed.
lbPaperSelector .SelectedIndex = 0

'Initialize combo boxes.
cbSupplier.Data Source = internalDataSet .Supplier 'The parent
tables to table Paper. Lots more of these in the actual code.
cbSupplier.Disp layMember = "Name"
cbSupplier.Valu eMember = "ID"
cbSize.DataSour ce = internalDataSet .Size
cbSize.DisplayM ember = "Name"
cbSize.ValueMem ber = "ID"

'Initialize text boxes.
tbItemNumber.Da taBindings.Add( "IntValue",
DirectCast(lbPa perSelector.Sel ectedItem, DataRowView).Ro w, "ItemNumber ")
End Sub

Private Sub lbPaperSelector _SelectedIndexC hanged(ByVal sender As Object,
ByVal e As System.EventArg s) Handles lbPaperSelector .SelectedIndexC hanged
'Update combo boxes.
cbSupplier.Sele ctedValue =
DirectCast(Dire ctCast(lbPaperS elector.Selecte dItem, DataRowView).Ro w,
Papers.PaperRow ).Supplier
cbSize.Selected Value =
DirectCast(Dire ctCast(lbPaperS elector.Selecte dItem, DataRowView).Ro w,
Papers.PaperRow ).Size
End Sub

[Cor Ligthert [MVP]]

Peter,

Have a look at the binding events at MSDN

Cor

"Peter" <st*****@hotmai l.comschreef in bericht
news:4V******** ********@newsre ad2.news.pas.ea rthlink.net...

Hi,

I'm trying to create a form that shows table rows in a listbox. Several
comboboxes expand the foreign key fields into text values from the parent
tables, and there are also some textboxes for the non-foreign key fields.
When the user clicks on a row in the listbox, the comboboxes' SelectedItem
changes to reflect the foreign key selections in the currently selected
row. That part is working fine. I also want the textboxes to change to
reflect the currently selected item's values.

I created a DataBinding in the textbox (actually, it's a custom control,
NumericTextBox, which only allows numeric values). The field that is bound
to the NumericTextBox is of type int. The property it is bound to
(IntValue) is of type Int32 (although I've tried many different types with
no luck). I've also tried using a plain textbox to no avail.

The problem is that, initially, the NumericTextBox displays the correct
value for the initially selected row. But if I enter that text box, I
can't leave it. And if I change the value of it, when I press tab, it
changes back to what it was. Also, if (before clicking it) I change to a
different row in the listbox, all the comboboxes update, but the textbox
does not. What's going on?

***
Private Sub PaperEditor_Loa d(ByVal sender As Object, ByVal e As
System.EventArg s) Handles MyBase.Load
'Initialize data binding for listbox.
lbPaperSelector .DataSource = internalDataSet .Paper 'The main
paper table, with foreign keys galore.
lbPaperSelector .DisplayMember = "FullText"
lbPaperSelector .ValueMember = "ID"

'Set selected item to the first paper listed.
lbPaperSelector .SelectedIndex = 0

'Initialize combo boxes.
cbSupplier.Data Source = internalDataSet .Supplier 'The parent
tables to table Paper. Lots more of these in the actual code.
cbSupplier.Disp layMember = "Name"
cbSupplier.Valu eMember = "ID"
cbSize.DataSour ce = internalDataSet .Size
cbSize.DisplayM ember = "Name"
cbSize.ValueMem ber = "ID"

'Initialize text boxes.
tbItemNumber.Da taBindings.Add( "IntValue",
DirectCast(lbPa perSelector.Sel ectedItem, DataRowView).Ro w, "ItemNumber ")
End Sub

Private Sub lbPaperSelector _SelectedIndexC hanged(ByVal sender As
Object, ByVal e As System.EventArg s) Handles
lbPaperSelector .SelectedIndexC hanged
'Update combo boxes.
cbSupplier.Sele ctedValue =
DirectCast(Dire ctCast(lbPaperS elector.Selecte dItem, DataRowView).Ro w,
Papers.PaperRow ).Supplier
cbSize.Selected Value =
DirectCast(Dire ctCast(lbPaperS elector.Selecte dItem, DataRowView).Ro w,
Papers.PaperRow ).Size
End Sub