WPF TreeviewItem header text is set to object type when using stackpanel

Question

I'm trying to make a treeview with items that has both image and text.

I have followed this example http://www.codeproject.com/Articles/124644/Basic-Understanding-of-Tree-View-in-WPF but I'm getting a strange behavior on the treeviewitem header.

The header is supposed to contain an image and a label but instead this is shown as the header text of all treeviewitems: System.Windows.Controls.StackPanel

Here is my code:

tree_view.Items.Add(GetTreeView("text"));

private TreeViewItem GetTreeView(string text)
{
    TreeViewItem newTreeViewItem = new TreeViewItem();

    // create stack panel
    StackPanel stack = new StackPanel();
    stack.Orientation = Orientation.Horizontal;

    // create Image
    Image image = new Image();
    image.Source = new BitmapImage(new Uri(@"/ComponentName;component/Resources/Images/warning.png", UriKind.Relative));

    // Label
    Label lbl = new Label();
    lbl.Content = text;

    // Add into stack
    stack.Children.Add(image);
    stack.Children.Add(lbl);

    // assign stack to header
    newTreeViewItem.Header = stack;

    return newTreeViewItem;
}

Edit:

Also, I have this in the TreeView's HeaderTemplate to wrap the text:

<Setter Property="HeaderTemplate">
     <Setter.Value>
         <DataTemplate>
             <TextBlock Width="139" TextWrapping="Wrap" Text="{Binding}" />
         </DataTemplate>
     </Setter.Value>
</Setter>

Have you set any templates, e.g. the TreeViewItem's [Template](http://msdn.microsoft.com/en-us/library/system.windows.controls.control.template) or the TreeView's [HeaderTemplate](http://msdn.microsoft.com/en-us/library/system.windows.controls.headereditemscontrol.headertemplate.aspx)? — Clemens, May 25 '12 at 09:04
Yes, I have set HeaderTemplate on the TreeView for wrapping the text. See the updated question above. — bale3, May 25 '12 at 09:21

score 1 · Answer 1 · edited May 25 '12 at 17:16

1

You can replace the TextBlock in your HeaderTemplate with ContentPresenter or remove the HeaderTemplate to get correct result.

Because of your HeaderTemplate setting, the header of TVI will display as text block and its data context changes to the stack panel.

edited May 25 '12 at 17:16

iCanHasFay

662
5
12

answered May 25 '12 at 10:00

lyphoon

66
3

score 0 · Accepted Answer · answered May 25 '12 at 09:50

I managed to fix this by removing the HeaderTemplate in the xaml.

Then, in my code-behind file I changed the Label to Textblock, then set the TextWrapping and Width-properties on the Textblock-object like this:

tree_view.Items.Add(GetTreeView("text"));

private TreeViewItem GetTreeView(string text)
{
    TreeViewItem newTreeViewItem = new TreeViewItem();

    // create stack panel
    StackPanel stack = new StackPanel();
    stack.Orientation = Orientation.Horizontal;

    // create Image
    Image image = new Image();
    image.Source = new BitmapImage(new Uri(@"/ComponentName;component/Resources/Images/warning.png", UriKind.Relative));

    // Label
    Textblock lbl = new Textblock();
    lbl.Text = text;
    lbl.TextWrapping = TextWrapping.Wrap;
    lbl.Width = 139;

    // Add into stack
    stack.Children.Add(image);
    stack.Children.Add(lbl);

    // assign stack to header
    newTreeViewItem.Header = stack;

    return newTreeViewItem;
}

WPF TreeviewItem header text is set to object type when using stackpanel

2 Answers2