WPF Treeview. No updating

I have a tree view with bind to some ObservableCollection, whi开发者_开发技巧ch is filled with some asyncronous function. The problem is that it's not getting updated on UI after the asyncronous command worked and updated the source collection (added some child nodes or something like that). My XAML looks like this:

<StackPanel>
    <StackPanel.Resources>
        <HierarchicalDataTemplate x:Key="CheckBoxItemTemplate"
            ItemsSource="{Binding Children, Mode=TwoWay}">
            <StackPanel Orientation="Horizontal">
                <CheckBox Focusable="False" IsChecked="{Binding IsChecked, Mode=TwoWay}"
                      VerticalAlignment="Center" />
                <ContentPresenter Content="{Binding Node.Caption, Mode=OneWay}" />
            </StackPanel>
        </HierarchicalDataTemplate>
    </StackPanel.Resources>

    <TreeView  Style="{DynamicResource FormItem}" ItemsSource="{Binding Nodes, Mode=TwoWay}" 
             ItemTemplate="{StaticResource CheckBoxItemTemplate}" >
    </TreeView>

</StackPanel>

Any suggestions?

Are you sure you're updating your UI on the correct thread?

Sorry for bothering you, guys. It was a silly mistake of mine. I just didn't set DataContexts of one control and of the window using this control. So it turned out that they had different contexts, because my ViewModel isn't a singleton. I should have been more careful about it.