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POListbox bound to ObservableCollection (in VB.NET and Silverlight)
 

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    <p>Sorry if this is a duplicate question. There are quite a few questions around this topic, but I can't seem to get it figured out. I'm trying to bind a listbox to an ObservableCollection and keep the listbox updated when items are added to the collection.</p> <p><strong>I have a class called CollectionOfBlogs:</strong></p> <pre><code>Public Class CollectionOfBlogs Implements INotifyPropertyChanged Public Event PropertyChanged As PropertyChangedEventHandler _ Implements INotifyPropertyChanged.PropertyChanged Public Sub New(ByVal name As String) Me.FullName = name End Sub Private _FullName As String Public Property FullName() As String Get Return _FullName End Get Set(ByVal value As String) _FullName = value NotifyPropertyChanged("FullName") End Set End Property Public Sub NotifyPropertyChanged(ByVal propertyName As String) RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propertyName)) End Sub End Class </code></pre> <p><strong>Then another class where I setup the ObservableCollection of CollectionOfBlogs (above) and a sub to add items to the collection:</strong></p> <pre><code>Public Class ITRSBlogs Public blogNamesList As New ObservableCollection(Of CollectionOfBlogs) Public Sub addBlog(ByVal FullName as String) blogNamesList.Add(New CollectionOfBlogs(FullName)) End Sub End Class </code></pre> <p><strong>I bind the listbox to the blogNamesList collection in the ITRSBlogs Class (above) from my main page loaded event:</strong></p> <pre><code>Dim blogClass As New ITRSBlogs Me.BloggingMenuListBox.ItemsSource = blogClass.blogNamesList </code></pre> <p><strong>Here is the XAML of my listbox. It's bound in the codebehind, not in the XAML (just thought I should mention that).</strong></p> <pre><code>&lt;ListBox Name="BloggingMenuListBox"/&gt; </code></pre> <p><strong>Before binding the collection to the listbox, I load the collection with items from the database, and they show up in the listbox just fine. These 2 subs below are actually in the ITRSBlogs Class as well, and I call FillBlogLists from my pages loaded event.</strong></p> <pre><code>Public Sub FillBlogLists() Dim query = theContext.GetBlogsOrderedByNameQuery theContext.Load(query, AddressOf OnBlogsLoaded, Nothing) End Sub Private Sub OnBlogsLoaded(ByVal lo As LoadOperation(Of Blog)) blogList.Clear() For Each s In lo.AllEntities blogList.Add(CType(s, Blog)) Next For Each item In blogList blogNamesList.Add(New CollectionOfBlogs(item.FullName)) Next End Sub </code></pre> <p><strong>Beyond this, I have a simple textbox and button on a page. When a name is entered into the textbox, and the button is clicked, I call the addBlog(passing in name from textbox) sub routine in the ITRSBlogs Class (back up the page a bit) to add the item to the collection.</strong></p> <p><strong>Problem is, when I add an item to the collection, the listbox is not updated. I'm new to Observable Collections (and many other things : ), so maybe I'm just really off here. Can anyone tell me what I'm doing wrong?</strong></p>
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