problem with combobox

[Dominique Vandensteen]

I posted this before but did some extra testing...

combobox with 3 elements (DropDownList style)
via code (button.click) I set the selectedIndex to -1
if element at index 0 is selected then everything is fine: nothing is
selected after pressing the button
but if element at index 1 or greater is selected and i press the button,
element at index 0 is selected (uncool)

i added a selectedindexch anged listener to my combobox
i can see it passes to index -1 and directly after that it passes again to
index 0

the result is the same in framework 1.0 and 1.1
anybody an idea?

testcode:
Private Sub Form1_Load(ByVa l sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load
Dim r As DataRow
Dim dt As DataTable
dt = New DataTable
dt.Columns.Add( "id")
dt.Columns.Add( "name")
dt.Rows.Add(New Object() {1, "one"})
dt.Rows.Add(New Object() {2, "toe"})
dt.Rows.Add(New Object() {3, "tie"})

ComboBox1.DataS ource = dt
ComboBox1.Displ ayMember = "name"
ComboBox1.Value Member = "id"
ComboBox1.Selec tedIndex = -1
End Sub

Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
ComboBox1.Selec tedIndex = -1
End Sub

Private Sub ComboBox1_Selec tedIndexChanged (ByVal sender As Object, ByVal e
As System.EventArg s) Handles ComboBox1.Selec tedIndexChanged
Debug.WriteLine (String.Format( "Selected index changed to [{0}]",
ComboBox1.Selec tedIndex))
End Sub

[Dominique Vandensteen]

aha
found it...
http://support.microsoft.com/default...b;en-us;327244

is a known bug, but seems only to be known for 1.0...
i still have it in 1.1

"Dominique Vandensteen" <domi.vds_inser t@tralala_tenfo rce.com> wrote in
message news:eh******** ******@TK2MSFTN GP09.phx.gbl...

I posted this before but did some extra testing...

combobox with 3 elements (DropDownList style)
via code (button.click) I set the selectedIndex to -1
if element at index 0 is selected then everything is fine: nothing is
selected after pressing the button
but if element at index 1 or greater is selected and i press the button,
element at index 0 is selected (uncool)

i added a selectedindexch anged listener to my combobox
i can see it passes to index -1 and directly after that it passes again to
index 0

the result is the same in framework 1.0 and 1.1
anybody an idea?

testcode:
Private Sub Form1_Load(ByVa l sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load
Dim r As DataRow
Dim dt As DataTable
dt = New DataTable
dt.Columns.Add( "id")
dt.Columns.Add( "name")
dt.Rows.Add(New Object() {1, "one"})
dt.Rows.Add(New Object() {2, "toe"})
dt.Rows.Add(New Object() {3, "tie"})

ComboBox1.DataS ource = dt
ComboBox1.Displ ayMember = "name"
ComboBox1.Value Member = "id"
ComboBox1.Selec tedIndex = -1
End Sub

Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
ComboBox1.Selec tedIndex = -1
End Sub

Private Sub ComboBox1_Selec tedIndexChanged (ByVal sender As Object, ByVal e
As System.EventArg s) Handles ComboBox1.Selec tedIndexChanged
Debug.WriteLine (String.Format( "Selected index changed to [{0}]",
ComboBox1.Selec tedIndex))
End Sub

[Cor]

Hi Dominique,

Did you test the sample I have send to you,
Because that did work on 1.1
And I was curious if it also did work on 1.0

Cor

is a known bug, but seems only to be known for 1.0...
i still have it in 1.1

[Herfried K. Wagner [MVP]]

* "Dominique Vandensteen" <domi.vds_inser t@tralala_tenfo rce.com> scripsit:

I posted this before but did some extra testing...

combobox with 3 elements (DropDownList style)
via code (button.click) I set the selectedIndex to -1
if element at index 0 is selected then everything is fine: nothing is
selected after pressing the button
but if element at index 1 or greater is selected and i press the button,
element at index 0 is selected (uncool)

Maybe setting it to -1 twice will help.

--
Herfried K. Wagner [MVP]
<http://www.mvps.org/dotnet>