HierarchicalDataTemplate for TreeView programmatically (C#).

Question

I have this class:

    public class Folder
    {
        private string _name;
        internal string Name
        {get { return _name; }}

        private List<Folder> _subfolders;
        internal List<Folder> Subfolders
        { get { return _subfolders; } }

        public Folder()
        {
            _name = "Root";
            _subfolders = new List<Folder>();
            _subfolders.Add(new Folder("F1"));
            _subfolders[0].Subfolders.Add(new Folder("F1.1"));
            _subfolders[0].Subfolders.Add(new Folder("F1.2"));

            _subfolders.Add(new Folder("F2"));
            _subfolders[1].Subfolders.Add(new Folder("F2.1"));
            _subfolders[1].Subfolders.Add(new Folder("F2.2"));
        }

        public Folder(string name)
        {
            _name = name;
            _subfolders = new List<Folder>();
        }
    }

and I want display instance of this class in TreeView, but after this call TreeView is empty. Does anybode know what is wrong?

        private void Sample()
        {
            Folder folder = new Folder();

            FrameworkElementFactory labelFactory = new FrameworkElementFactory(typeof(TextBlock));

            //1. We have to define type of items
            HierarchicalDataTemplate template = new HierarchicalDataTemplate(typeof(Folder));
            //2. We have to define source for subitems
            template.ItemsSource = new Binding("Subfolders");
            //3. We have to define DataTemplate for items
            labelFactory.SetBinding(TextBlock.TextProperty, new Binding("Name"));
            template.VisualTree = labelFactory;

            treeView1.ItemTemplate = template;
            treeView1.ItemsSource = folder.Subfolders;
        }

Regards

Answer 1

Your code works for me....are you sure your Sample() method is getting called?

Where is treeView1 defined?


Mark

---

Mark Salsbery Microsoft MVP - Visual C++

Answer 2

Yes I am sure that Sample() is called :-)
treeView1 is defined in XAML in Grid and Grid is defined in Window.

Answer 3

Yes I am sure that Sample() is called :-)
treeView1 is defined in XAML in Grid and Grid is defined in Window.

I just realized I DID make a change to your code.....I did it almost subconsciously when I first copied it because I knew it wouldn't work correctly if I didn't change it...

You need to change any properties you bind to in your data class(es) to "public" instead of "internal".


Mark

---

Mark Salsbery Microsoft MVP - Visual C++

Answer 4

Now it works !
Thanks !

Answer 5

Will you please explain me how can I create the xaml for this example and please if you have any other example
it will be better.

I want to be able to create a complex TreeView with images and text, with different formats for different levels and at the same
time I don't want to use the namespace in the xaml to define the DataType and the ItemsSource, I want to do the binding programmatically if it is possible.

Thanks in advance.

Answer 6

Any answer?

Answer 7

Will you please explain me how can I create the xaml for this example

For this example I used

<TreeView Name="treeView1" />

You may get better forum results if you start a new thread.


Mark

---

Mark Salsbery Microsoft MVP - Visual C++