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POComboBox.SelectedValue not updating from binding source
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  1. POComboBox.SelectedValue not updating from binding source
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    copied!<p>Here's my binding source object: </p> <pre><code>Public Class MyListObject Private _mylist As New ObservableCollection(Of String) Private _selectedName As String Public Sub New(ByVal nameList As List(Of String), ByVal defaultName As String) For Each name In nameList _mylist.Add(name) Next _selectedName = defaultName End Sub Public ReadOnly Property MyList() As ObservableCollection(Of String) Get Return _mylist End Get End Property Public ReadOnly Property SelectedName() As String Get Return _selectedName End Get End Property End Class </code></pre> <p>Here is my XAML:</p> <pre><code>&lt;Window x:Class="Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Window1" Height="300" Width="300" xmlns:local="clr-namespace:WpfApplication1" &gt; &lt;Window.Resources&gt; &lt;ObjectDataProvider x:Key="MyListObject" ObjectInstance="" /&gt; &lt;/Window.Resources&gt; &lt;Grid&gt; &lt;ComboBox Height="23" Margin="24,91,53,0" Name="ComboBox1" VerticalAlignment="Top" SelectedValue="{Binding Path=SelectedName, Source={StaticResource MyListObject}, Mode=OneWay}" ItemsSource="{Binding Path=MyList, Source={StaticResource MyListObject}, Mode=OneWay}" /&gt; &lt;Button Height="23" HorizontalAlignment="Left" Margin="47,0,0,87" Name="btn_List1" VerticalAlignment="Bottom" Width="75"&gt;List 1&lt;/Button&gt; &lt;Button Height="23" Margin="0,0,75,87" Name="btn_List2" VerticalAlignment="Bottom" HorizontalAlignment="Right" Width="75"&gt;List 2&lt;/Button&gt; &lt;/Grid&gt; &lt;/Window&gt; </code></pre> <p>Here's the code-behind:</p> <pre><code>Class Window1 Private obj1 As MyListObject Private obj2 As MyListObject Private odp As ObjectDataProvider Public Sub New() InitializeComponent() Dim namelist1 As New List(Of String) namelist1.Add("Joe") namelist1.Add("Steve") obj1 = New MyListObject(namelist1, "Steve") . Dim namelist2 As New List(Of String) namelist2.Add("Bob") namelist2.Add("Tim") obj2 = New MyListObject(namelist2, "Tim") odp = DirectCast(Me.FindResource("MyListObject"), ObjectDataProvider) odp.ObjectInstance = obj1 End Sub Private Sub btn_List1_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles btn_List1.Click odp.ObjectInstance = obj1 End Sub Private Sub btn_List2_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles btn_List2.Click odp.ObjectInstance = obj2 End Sub End Class </code></pre> <p>When the Window first loads, the bindings hook up fine. The ComboBox contains the names "Joe" and "Steve" and "Steve" is selected by default. However, when I click a button to switch the ObjectInstance to obj2, the ComboBox ItemsSource gets populated correctly in the dropdown, but the SelectedValue is set to Nothing instead of being equal to obj2.SelectedName.</p>
 

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