Find Silverlight TreeViewItem control by Header

Question

I am trying to create a TreeView from the Silverlight TreeView control. I have my data being pulled from a WCF service that pulls from EF. All of the data is coming in fine. I have the page set up where I can input a UserName, click a button, and the data will populate the first generation in the TreeView. So, I'm dynamically building TreeViewItems to put into my TreeView with a Selected RoutedEventHandlers attached to each one. When I click on one of the TreeViewItem nodes, it kicks off the tvi_Selected function in which I want to populate TreeViewItems under the TreeViewItem that I just selected.

I run into problem when I am in my delegate function prox_GetChildMembersCompleted. I can't figure out a way to do a FindControl type lookup on the TreeViewItem that I want to add the child TreeViewItem elements to. So, I thought that I would just create a protected field where I would store the Header information to because it contain only the UserName. I just need to be able to access a specific TreeViewItem by Header or some other method that is alluding me.

You can see that in my Selected eventhandler, that I am getting the Header info by casting the sender object to a TreeViewItem. In the the delegate function prox_GetChildMembersCompleted that is called inside of tvi_Selected, the sender object is WCFDataClient so I can't grab the same data from that sender. Any insight into this would be much appreciated even if you suggest a method that is completely different.

<UserControl xmlns:controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls"  
    xmlns:data="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data"
    x:Class="FloLOS2.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480">
  <Grid x:Name="LayoutRoot" Background="#5C7590">
        <StackPanel>
            <TextBox x:Name="txtUserName" Width="120" Margin="5"></TextBox>
            <TextBlock x:Name="txtFillBlock" Width="300" Margin="5" Foreground="White" Text="Change me"></TextBlock> 
            <Button x:Name="btnSubmit" Margin="5" Content="Get Frontline" Width="120" Click="btnSubmit_Click" />
            <data:DataGrid x:Name="MembersGrid" Margin="5"></data:DataGrid>
            <controls:TreeView x:Name="MembersTree" Margin="5"></controls:TreeView>
        </StackPanel>
    </Grid>
</UserControl>



namespace FloLOS2
{
    public partial class MainPage : UserControl
    {
        string sParentID;

        public MainPage()
        {
            InitializeComponent();
        }

        private void btnSubmit_Click(object sender, RoutedEventArgs e)
        {
            GetMyDataRef.GetMyDataClient prox = new FloLOS2.GetMyDataRef.GetMyDataClient();
            prox.GetMembersCompleted += new EventHandler<FloLOS2.GetMyDataRef.GetMembersCompletedEventArgs>(prox_GetMembersCompleted);
            prox.GetMembersAsync(txtUserName.Text);
        }

        void prox_GetMembersCompleted(object sender, FloLOS2.GetMyDataRef.GetMembersCompletedEventArgs e)
        {
            GetMyDataRef.Member[] members = e.Result.ToArray();

            foreach (var x in members)
            {
                TreeViewItem tvi = new TreeViewItem() { Header = x.UserName };
                tvi.Selected += new RoutedEventHandler(tvi_Selected);
                MembersTree.Items.Add(tvi);
            }

            //MembersTree.Items.Add(tvi);
        }

        void prox_GetChildMembersCompleted(object sender, FloLOS2.GetMyDataRef.GetMembersCompletedEventArgs e)
        {
            GetMyDataRef.Member[] members = e.Result.ToArray();
            TreeViewItem tviParent = new TreeViewItem();
            // *** Find TreeViewItem control based on Header  ***

            foreach (var x in members)
            {
                TreeViewItem tviChild = new TreeViewItem() { Header = x.UserName };
                tviChild.Selected += new RoutedEventHandler(tvi_Selected);
                tviParent.Items.Add(tviChild);
            }

        }

        void tvi_Selected(object sender, RoutedEventArgs e)
        {
            try
            {

                TreeViewItem item = (TreeViewItem)sender;
                txtFillBlock.Text = item.Header.ToString();
                sParentID = item.Header.ToString();

                GetMyDataRef.GetMyDataClient prox = new FloLOS2.GetMyDataRef.GetMyDataClient();
                prox.GetMembersCompleted += new EventHandler<FloLOS2.GetMyDataRef.GetMembersCompletedEventArgs>(prox_GetChildMembersCompleted);
                prox.GetMembersAsync(item.Header.ToString());

            }
            catch (Exception ex)
            {
                txtFillBlock.Text = ex.InnerException.ToString();
            }
        }


    }
}

Answer 1

I figured out a way to do it. I went and assigned a Name to the dynamically generated TreeViewItems as the UserName. I also stored the sender UserName in a protected string, then called this line of code to get the parent TreeViewItem:

    TreeViewItem tviParent = (TreeViewItem)LayoutRoot.FindName(sParentID);

Thanks for what would have been great answers! :)