Workaround:
RadTreeView1.TreeViewElement.TreeNodeProvider.Reset()

To reproduce: Add some nodes to a tree, and then clear them and move them to another tree. The inner nodes expand/collapse does not work correctly: void radButton1_Click(object sender, EventArgs e) { tree1.Nodes.Clear(); tree2.Nodes.AddRange(nodes); } RadTreeView tree1 = new RadTreeView(); RadTreeView tree2 = new RadTreeView(); List<RadTreeNode> nodes = new List<RadTreeNode>(); private void Populate(RadTreeView tree) { RadTreeNode n11 = new RadTreeNode("11"); RadTreeNode n12 = new RadTreeNode("12"); RadTreeNode n13 = new RadTreeNode("13"); RadTreeNode n14 = new RadTreeNode("14"); nodes.Add(n11); nodes.Add(n12); nodes.Add(n13); nodes.Add(n14); RadTreeNode n21 = new RadTreeNode("21"); RadTreeNode n22 = new RadTreeNode("22"); RadTreeNode n23 = new RadTreeNode("23"); RadTreeNode n24 = new RadTreeNode("24"); n11.Nodes.Add(n21); n11.Nodes.Add(n22); n11.Nodes.Add(n23); n11.Nodes.Add(n24); RadTreeNode n31 = new RadTreeNode("31"); RadTreeNode n32 = new RadTreeNode("32"); RadTreeNode n33 = new RadTreeNode("33"); RadTreeNode n34 = new RadTreeNode("34"); n21.Nodes.Add(n31); n21.Nodes.Add(n32); n21.Nodes.Add(n33); n21.Nodes.Add(n34); tree.Nodes.AddRange(nodes); } 1. Run 2. Expand all nodes in tree1 3. Select node 23 4. Press button move right 5. Click at "plus" at node 21. -> expand collapse does not work correctly Workaround - instead of calling the Clear method of the Nodes collection, remove them manually: while (tree1.Nodes.Count > 0) { tree1.Nodes.RemoveAt(0); }

FIX. RadTreeView - the tree should keep its selection, expanded nodes and scroll position when new record is added to its underlying data source

If user move on last node of the tree view and move the mouse downwards then "NodeMouseLeave" event does not get fired and if user move left side of the node then it's working fine.

To reproduce: 
  void radTreeView1_EditorInitialized(object sender, TreeNodeEditorInitializedEventArgs e)
        {
            TreeViewTextBoxEditor editor = e.Editor as TreeViewTextBoxEditor;
            BaseTextBoxEditorElement element = (BaseTextBoxEditorElement)editor.EditorElement;
            element.TextChanging+=new TextChangingEventHandler(element_TextChanging);
        }

        void  element_TextChanging(object sender, TextChangingEventArgs e)
        {
            e.Cancel = true;
        }

When I execute TreeView.SelectedNodes.Clear() during runtime, the SelctedNodeChanged event is not fired letting me know that the current selected node was changed to no selection. Should that qualify for a selection change event? Eessentially, the selected node has changed, but to no selection. The SelectedNodeChanging event does not fire as well.

What event will let me know that a selection has been removed (changed)?

Workaround:
this.radTreeView1.SelectedNode = null;

To reproduce: private void btnFill_Click(object sender, EventArgs e) { radTreeView.BeginUpdate(); radTreeView.Nodes.Add(new RadTreeNode("root 1")); radTreeView.Nodes.Add(new RadTreeNode("root 2")); radTreeView.Nodes.Add(new RadTreeNode("root 3")); radTreeView.Nodes.Add(new RadTreeNode("root 4")); radTreeView.Nodes[radTreeView.Nodes.Count - 1].Expand(); for (int i = 0; i < 30; i++) { radTreeView.Nodes[radTreeView.Nodes.Count - 1].Nodes.Add(new RadTreeNode("text" +i)); } radTreeView.EndUpdate(); } private void radButton1_Click(object sender, EventArgs e) { radTreeView.BeginUpdate(); foreach (var node in radTreeView.Nodes[radTreeView.Nodes.Count - 1].Nodes.ToArray()) { node.Remove(); } for (int i = 0; i < 99; i++) { radTreeView.Nodes[radTreeView.Nodes.Count - 1].Nodes.Add(new RadTreeNode("aasdasd")); } radTreeView.EndUpdate(); } Workaround - reset the traverser and update the scroll value prior removing the nodes radTreeView.TreeViewElement.Scroller.Traverser.Reset(); 

this.treeView.TreeViewElement.Scroller.UpdateScrollValue();

To reproduce: this issue is reproducible under Windows8 OS only
-add RadTreeView from the Toolbox to the Form and add several tree nodes at design time;
-add RadContextMenu from the Toolbox and add several items at design time;
Use the following code:
public Form1()
{
    InitializeComponent();

    this.radTreeView1.RadContextMenu = this.radContextMenu1;
}
-run the application;
-select a tree node;
-right mouse click over the node to show the context menu; As a result the main form looses focus and you are unable to click anywhere outside the RadTreeView.
This issue is inconstant and it is not appearing every time.

Workaround: use ContextMenu property instead:
public Form1()
{
    InitializeComponent();

    ContextMenu menu = new ContextMenu();

    foreach (var item in radContextMenu1.Items)
    {
        menu.MenuItems.Add(new MenuItem(item.Text));
    }

    this.radTreeView1.ContextMenu = menu;
    // this.radTreeView1.RadContextMenu = this.radContextMenu1;
}

To reproduce:
Add a RadTreeView with some nodes and you will notice that the font is different than other controls.

Workaround:
void tree_NodeFormatting(object sender, TreeNodeFormattingEventArgs e)
{
    e.NodeElement.ContentElement.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SystemDefault;
}

The issue is valid for Windows 7 and Windows 8 based devices and related to accessibility objects support in our suite

The event is fired then drag and drop is performed in unbound mode but not when in bound mode

When a tree is bound using object-relational binding the editing does not work for nodes that are on level higher than the first.

NullReferenceException in the UpdateLines method somehow triggered by the OnProcessMouseUp handler, when I'm trying to perform a drag and drop move in my treeview, that is fully managed by an inner model. The DnD events are bound and trigger delete + add actions in the tree.

The RadTreeView does not reset the SelectedNode when the nodes are cleared in unbound mode.

FIX. RadTreeView - CreateNode event is not fired when adding a node from the New menu item in the context menu

Workaround: Use the NodeAdding/NodeAdded events.

To reproduce:
- populate a tree with some nodes in different levels


- set the ShowLines to true
- select a node on the second level
- clear the nodes on a button click => exception is thrown

WORKAROUND:
radTreeView1.ShowLines = false; 
radTreeView1.Nodes.Clear(); 
radTreeView1.ShowLines = true;

bind the tree and try to add a node to the control - error occurs

The following code produces an error when the user attempts to edit the root node:
DataTable dt = new DataTable();
DataColumn column = new DataColumn("ID", typeof(int));
column.AllowDBNull = false;
column.AutoIncrement = true;
dt.Columns.Add(column);
dt.Columns.Add(new DataColumn("ParentID", typeof(int)));
dt.Columns.Add(new DataColumn("Name", typeof(string)));
dt.Columns.Add(new DataColumn("Note", typeof(string)));
dt.Rows.Add(1, DBNull.Value, "Root", "Note1");
dt.Rows.Add(2, 1, "First", "Note1");
dt.Rows.Add(3, 1, "Second", "Note1");
dt.Rows.Add(4, 3, "Third", "Note1");
this.radTreeView1.DisplayMember = "Name";
this.radTreeView1.ParentMember = "ParentID";
this.radTreeView1.ChildMember = "ID";
this.radTreeView1.ValueMember = "ID";
this.radTreeView1.DataSource = dt;
radTreeView1.TreeViewElement.EditMode = TreeNodeEditMode.Text;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Telerik.WinControls.UI;
namespace Lab.Tree
{
public partial class TreeSelfreferenceEditRootNodeForm : Form
{
private RadTreeView treeView = new RadTreeView();
private BindingSource bindingSource = new BindingSource();
public TreeSelfreferenceEditRootNodeForm()
{
InitializeComponent();
treeView.Dock = DockStyle.Fill;
treeView.Parent = this;
treeView.AllowEdit = true;
DataTable dt = new DataTable();
DataColumn column = new DataColumn("ID", typeof(int));
column.AllowDBNull = false;
column.AutoIncrement = true;
dt.Columns.Add(column);
dt.Columns.Add(new DataColumn("ParentID", typeof(int)));
dt.Columns.Add(new DataColumn("Name", typeof(string)));
dt.Columns.Add(new DataColumn("Note", typeof(string)));
dt.Rows.Add(1, DBNull.Value, "Root", "Note1");
dt.Rows.Add(2, 1, "First", "Note1");
dt.Rows.Add(3, 1, "Second", "Note1");
dt.Rows.Add(4, 3, "Third", "Note1");
bindingSource.DataSource = dt;
treeView.DisplayMember = "Name";
treeView.ParentMember = "ParentID";
treeView.ChildMember = "ID";
treeView.ValueMember = "ID";
treeView.DataSource = bindingSource;
treeView.TreeViewElement.EditMode = TreeNodeEditMode.Text;
}
}
}

1. Create a new project and add empty RadTreeView when handling its Form.Load event.
2. Set its AutoSize property to true.
3. Run the project.