How to make it scroll to the top after resin the Silverlight ListBox control?

 
  
  Height="25"/>
 
  ScrollViewer.HorizontalScrollBarVisibility="Auto"
 ScrollViewer.VerticalscrollbarVisibility="Auto">
 < br /> 
 
 
 
 
 
 
 

Imports System.Threading
Imports System.Collections.ObjectModel
Imports System.ComponentModel
Partial Public Class ucSearch 
 Inherits UserControl
 Private WithEvents BGwork As New BackgroundWorker()
 Private mReportList as New List(Of cFilter)

 Public Sub New()
 InitializeComponent( )
 FillReportList()
 NewFilterList()
 End Sub

 Private Sub FillReportList()
 mReportList.Add(new cFilter("Report A", "Report A desc")
 mReportList.Add(new cFilter("Report B", "Report B desc")
 mReportList.Add(new cFilter("Report C", "Report C desc") 
 mReportList.Add(new cFilter("Report D", "Report D desc")
 mReportList.Add(ne w cFilter("Report E", "Report E desc")
 mReportList.Add(new cFilter("Report F", "Report F desc")
 mReportList.Add(new cFilter("Report G ", "Report G desc")
 mReportList.Add(new cFilter("Report H", "Report H desc")
 mReportList.Add(new cFilter("Report I", "Report I desc ")
 mReportList.Add(new cFilter("Report J", "Report J desc")
 mReportList.Add(new cFilter("Report K", "Report K desc")
 mReportList.Add(new cFilter("Report L", "Report L desc")
 mReportList.Add(new cFilter("Report M", "Report M desc")
 End Sub
 
 Private Sub textboxSearch_KeyUp(ByVal sender as System.Object, _
 ByVal e as System.Windows.Input.KeyeventArgs)
 NewFilterList()
 End Sub

 Private Sub NewFilterList()
 If BGwork.IsBusy Then
 If Not BGWork.cancellationPending Then BGwork.Can celAsync()
 Exit Sub
 End If

 With BGwork
 .WorkerSupportsCancellation = True
 .RunWorkerAsync(textboxSearch.Text)
 End With 
 End Sub

 Private Sub BGwork_DoWork(ByVal sender as Object, _
 ByVal e as System.ComponentModel.DoWorkEventArgs) _
 Handles BGwork.DoWork
 Dim Filtered as New List(of cFilter)
 If textboxSearch.Text.Length> 0
 dim q = FROM ri In mReportList Where ri.Reportname.ToLower.contains(textboxSearch.Text.ToLower) Select ri< br /> Filtered = q
 Else
 Filtered = mReportList
 End If
 Dim RTN as List(Of cFilter) = Filtered
 e.Cancel = False
 e.Result = RTN
 End Sub

 Private Sub BGwork_RunWorkerCompleted(ByVal sender As Object_
 ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) _
 Handles BGwork.RunWorkerCompleted
 If e.Cancelled Then
 NewFilterList()
 Exit Sub
 End If

 Dim RTN as cFilter = TryCast(e.Result, cFilter)
 If IsNothing(RTN) Then Exit Sub

 SearchResultBox.ItemsSource = RTN< br /> SearchResultBox.InvalidateArrange()
 End Sub
 End Class

 Public Class cFilter
 Inherits BaseDataClass
 Private mReportName as String = ""
 Private mReportDescription as String = ""

 Public Sub New()
 mReportName = ""
 mReportDescription = ""
 End Sub

 Public Sub New(ByVal reportName as String, ByVal reportDescription as String)
 mReport Name = reportName
 mReportDescription = reportDescription
 End Sub

 Public Property ReportName() as String
 Get
 Return mReportName
 End Get
 Set(ByVal value as String)
 mReportName = value
 End Set
 End Property

 Public Property ReportDescription() as String
 Get
 Return mReportDescription
 End Get
 Set(ByVal value as String)
 mReportDescription = value
 End Set
 End Property
 End Class

theListBox.ItemsSource = data;
 theListBox. UpdateLayout();
 theListBox.ScrollIntoView(theListBox.Items[0]);

I have a silverlight list box used as a search result box. I am working Use dynamic search (the keyboard in the search box will cause an event to be triggered to filter the contents of this list box). The problem I have is that if the user scrolls down without filtering and then searches, the list is re-bound The box does not cause the scroll to return to the top, making the result seem to have only one value.

The code for the list box I have so far is this (this is a simplified version):

XAML:

 
 
  Height="25"/>
 
  ScrollViewer.HorizontalScrollBarVisibility=" Auto"
 ScrollViewer.Verticalscr ollbarVisibility="Auto">
 
 
 
  
 
 
 
 
  

VB:

Imports System.Threading
Imports System.Collections.ObjectModel
Imports System.ComponentModel
Partial Public Class ucSearch
 Inherits UserControl
 Private WithEvents BGwork As New BackgroundWorker()
 Private mReportList as New List(Of cFilter)

 Public Sub New()
 InitializeComponent()
 FillReportList()
 NewFilterList()
 End Sub

 Private Sub FillReportList()
 mReportList .Add(new cFil ter("Report A", "Report A desc")
 mReportList.Add(new cFilter("Report B", "Report B desc")
 mReportList.Add(new cFilter("Report C" , "Report C desc")
 mReportList.Add(new cFilter("Report D", "Report D desc")
 mReportList.Add(new cFilter("Report E", "Report E desc" )
 mReportList.Add(new cFilter("Report F", "Report F desc")
 mReportList.Add(new cFilter("Report G", "Report G desc")
 mReportList .Add(new cFilter("Report H", "Report H desc")
 mReportList.Add(new cFilter("Report I", "Report I desc")
 mReportList.Add(new cFilter( "Report J", "Report J desc")
 mReportList.Add(new cFilter("Report K", "Report K desc")
 mReportList.Add(new cFilter("Report L", " Report L desc")
 mReportList.Add(new cFilter("Report M", "Report M desc")
 End Sub

 Private Sub textboxSearch_KeyUp(ByVal sender as System. Object, _
 ByVal e as System.Windows.Input.KeyeventArgs)
 NewFilterList()
 End Sub

 Private Sub NewFilterList()
 If BGwork.IsBusy Then
 If Not BGWork.cancellationPending Then BGwork.CancelAsync()
 Exit Sub
 End If

 With BGwork
 .WorkerSupportsCancellation = True
 .RunWorkerAsync(textboxSearch .Text)
 End With
 End Sub

 Private Sub BGwork_DoWork(ByVal sender as Object, _
 ByVal e as System.ComponentModel.DoWorkEventArgs) _
 Handles BGwork.DoWork
 Dim Filtered as New List(of cFilter)
 If textboxSearch.Text.Length> 0
 dim q = FROM ri In mReportList Where ri.Reportname.ToLower.contains( textboxSearch.Text.ToLower) Select ri
 Filtered = q
 Else
 Filtered = mReportList
 End If
 Dim RTN as List(Of cFilter) = Filtered
 e.Cancel = False
 e.Result = RTN
 End Sub

 Private Sub BGwork_RunWorkerCompleted(ByVal sender As Object_
 ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) _
 Handles BGwork.RunWorkerCompleted
 If e.Cancelled Then
 NewFilterList()
 Exit Sub
 End If

 Dim RTN as cFilter = TryCast(e.Result, cFilter)
 If IsNothing (RTN) Then Exit Sub

 SearchResultBox.ItemsSource = RTN
 SearchResultBox.InvalidateArrange()
 End Sub
 End Class

 Public Class cFilter
 Inherits BaseDataClass
 Private mReportName as String = ""
 Priv ate mReportDescription as String = ""

 Public Sub New()
 mReportName = ""
 mReportDescription = ""
 End Sub

 Public Sub New(ByVal reportName as String, ByVal reportDescription as String)
 mReportName = reportName
 mReportDescription = reportDescription
 End Sub

 Public Property ReportName() as String< br /> Get
 Return mReportName
 End Get
 Set(ByVal value as String)
 mReportName = value
 End Set
 End Property
 
 Public Property ReportDescription() as String
 Get
 Return mReportDescription
 End Get
 Set(ByVal value as String)
 mReportDescription = value
 End Set
 End Property
 End Class

Once again, this and what happened is greatly simplified (I go to the database to get the report name, etc.). When I re-bind When defining a list box, how do I keep it scrolling so that the first item is at the top of the list? Since I cannot access the scrollviewer control in the ListBox object, do I have to create a scrollviewer control around the list box and then set its view position?

After reading this article

Automatic Scrolling in a Silverlight List Box

I try I added the following and it works fine for me.

theListBox.ItemsSource = data;
 theListBox.UpdateLayout();
 theListBox.ScrollIntoView( theListBox.Items[0]);