Add a possibility to set the auto-expand delay on drag-drop in RadTreeView.

Currently we do not support binding to the ToggleState.Indeterminate state automatically because it would require a change in the behavior of the Checked property. If you use the CheckedMember, the ToggleState.Indeterminate state is represent like ToggleState.On. 

Workaround: 
Subscribe to the NodeFormatting and NodeCheckedChanged events: 
void radTreeView1_NodeFormatting(object sender, Telerik.WinControls.UI.TreeNodeFormattingEventArgs e)
{
    Child child = e.Node.DataBoundItem as Child;
    if (child != null)
    {
        e.Node.CheckState = child.Status;
    }
}

void radTreeView1_NodeCheckedChanged(object sender, Telerik.WinControls.UI.TreeNodeCheckedEventArgs e)
{
    Child child = e.Node.DataBoundItem as Child;
    if (child != null)
    {
        child.Status = e.Node.CheckState;
    }
}

Hi all,

RadTreeView is very nice control , For treeline we can give line style, color but we can't set line thickness,

I want to change thickness of Treeline can you guide me how to do it?

At the moment the filter predicate is called only for the root nodes. A possible workaround is to recursively apply the filter logic for the child nodes as well.
Workaround:
private void Button1_Click(object sender, EventArgs e)
{
    this.radTreeView1.TreeViewElement.FilterPredicate = this.FilterNode;
    this.radTreeView1.Filter = "Custom";
}

private bool FilterNode(RadTreeNode node)
{
    Console.WriteLine(node.Text);
    if (node.Text.Contains("Child: 3"))
    {
        return true;
    }

    Stack<RadTreeNode> children = new Stack<RadTreeNode>();
    if (node.Nodes.Count > 0)
    {
        children.Push(node);
        while (children.Count > 0)
        {
            RadTreeNode current = children.Pop();
            foreach (RadTreeNode child in current.Nodes)
            {
                if (child.Text.Contains("Child: 3"))
                {
                    return true;
                }

                children.Push(child);
            }
        }
    }

    return false;
}

Workaround:

        class CustomTreeView : RadTreeView
        {
            //Replace the default element with the custom one
            protected override RadTreeViewElement CreateTreeViewElement()
            {
                return new CustomTreeViewElement();
            }

            //Enable theming for the control
            public override string ThemeClassName
            {
                get
                {
                    return typeof(RadTreeView).FullName;
                }
            }
        }

        class CustomTreeViewElement : RadTreeViewElement
        {
            //Enable themeing for the element
            protected override Type ThemeEffectiveType
            {
                get
                {
                    return typeof(RadTreeViewElement);
                }
            }

            protected override bool ProcessContextMenu(Point location)
            {
                RadTreeNode node = this.GetNodeAt(location);
                if (node == null)
                {
                    RadContextMenu menu = new RadContextMenu();
                    RadMenuItem item = new RadMenuItem();
                    item.Text = "Add a root node";
                    menu.Items.Add(item);
                    item.Click += item_Click;
                    TreeViewContextMenuOpeningEventArgs args = new TreeViewContextMenuOpeningEventArgs(node, menu);
                    OnContextMenuOpening(args);

                    if (!args.Cancel)
                    {
                        menu.Show(this.ElementTree.Control, location);
                        return true;
                    }
                }
                return base.ProcessContextMenu(location);
            }

            private void item_Click(object sender, EventArgs e)
            {
                this.Nodes.Add(new RadTreeNode("New root"));
            }
        }

RadTreeView - export, print content

possible supported file types: pdf, excel, html

drag select nodes. I.e - Left click and drag to highlight / select a bunch of nodes in a treeview. 
Ticket ID: 319445

Improve the drag and drop indicators by giving more clean user friendly design and positioning.

Similar functionality like in KendoUI or WPF

ADD. RadTreeView - when pressing a letter from the keyboard, the node starting with this letter should be selected.

Resolution: 
Added two new properties: KeyboardSearchEnabled and KeyboardSearchResetInterval. When set the KeyboardSearchEnabled property to true, user can navigate to an item by typing when RadTreeView is focused. 
You can set how long the user must wait before searching with the keyboard is reset using the KeyboardSearchResetInterval property. 

ADD. RadTreeView - add support for binding the checkboxes of the nodes to a field in the data

I can type to select a node.  For example, if I click to select the Car node, then type "V", selection jumps to the "Van" node.  I can right-arrow to expand, then type "U" to select the "Useful" node.

Resolution: 
Added two new properties: KeyboardSearchEnabled and KeyboardSearchResetInterval. When set the KeyboardSearchEnabled property to true, user can navigate to an item by typing when RadTreeView is focused. You can set how long the user must wait before searching with the keyboard is reset using the KeyboardSearchResetInterval property. 

Add TreeViewXml property to RadTreeView that allows xml serialization by string type

Add CheckedNodes collection of RadTreeView that contains all checked nodes.

ADD SaveXML and LoadXML method of RadTreeView that allows loading and saving xml via stream

Set separate indent for every node in RadTreeView. Currently we support setting the same indent for every node thorough TreeIndent property.

Add e.Action in SelectedNodeChanging similar to the one in the standard TreeView.BeforeSelect event which indicates what caused the event - mouse click, key pressed, or other