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POlistBox.ItemContainerGenerator.ContainerFromItem() returns null to the NEW item added in the listbox
 

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    <p>This is my first post here so I hope you could help me with my problem regarding WPF.</p> <p>I have a listbox that is bind with an ObservableCollection:</p> <pre><code> public ObservableCollection&lt;DeviceSetting&gt; DeviceSettings { get { return _deviceSettings; } set { _deviceSettings = value; } } &lt;ListBox ItemTemplate="{StaticResource IPItemTemplate}" Name="listBoxAddresses" SelectionMode="Extended" ItemsSource="{Binding Path=TestSetting.DeviceSettings, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}" ItemContainerStyle="{StaticResource ContainerStyle}" /&gt; </code></pre> <p>The situation here is, I would like to know if a new item has been added to the list so what I did was create a CollectionChanged event:</p> <pre><code>TestSetting.DeviceSettings.CollectionChanged += mListBox_CollectionChanged; private void mListBox_CollectionChanged(object sender,NotifyCollectionChangedEventArgs e) { if (e.Action == NotifyCollectionChangedAction.Add) { for (int i = 0; i &lt; TestSetting.DeviceSettings.Count; i++){ ListBoxItem myListBoxItem = (ListBoxItem)(listBoxAddresses.ItemContainerGenerator.ContainerFromItem(listBoxAddresses.Items[i])); if (!TestSetting.DeviceSettings[i].IsNetwork &amp;&amp; DeviceDiscovery.IsSelected) myListBoxItem.IsEnabled = false; else if (TestSetting.DeviceSettings[i].IsNetwork &amp;&amp; !DeviceDiscovery.IsSelected) myListBoxItem.IsEnabled = false; else myListBoxItem.IsEnabled = true; } } </code></pre> <p>But a problem occurs at this statement:</p> <pre><code>ListBoxItem myListBoxItem = (ListBoxItem)(listBoxAddresses.ItemContainerGenerator.ContainerFromItem(listBoxAddresses.Items[i])); </code></pre> <p>Everytime I added a new item, the statement above always returns null so the new item that was added was not checked if would be enabled or not. Is there a way for this statement to return the correct ListBoxItem that I need?</p>
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    1. COWhy just not use bindings inside ItemTemplate (with a help of some Converter)? You\`re checking properies anyway, you only do this manually right now.
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