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I think you may need to show a bit more code for what you're trying to do. There shouldn't be anything noticeably different drawing like that, versus not owner drawing at all; you're basically overriding the default draw and then undoing it in what you posted. It's ugly for no gain... but shouldn't be a perf hit. So switching away from the lack of code and going after your core desire of a custom drawn tree, let me tell you that there is NOT a lot of good information out in the wild right now. I've been doing my own custom treeview work over the past few days and will probably end up writing a tutorial on all that I've learned. In the meantime feel free to take a look at my code and see if it helps you out. Mine was simply a custom drawn explorer treeview. The code that populates the treeview is separate from the TreeView drawing code. You'll probably need to add your own +/- images if you wanted to run my code. Utilities\IconReader.cs <pre><code>using System; using System.Runtime.InteropServices; namespace TreeViewTestProject.Utilities { public class IconReader { public enum IconSize { Large = 0, Small = 1 }; public enum FolderType { Open = 0, Closed = 1 }; /// <summary> /// Returns an icon for a given file - indicated by the name parameter. /// </summary> /// <param name="name">Pathname for file.</param> /// <param name="size">Large or small</param> /// <param name="linkOverlay">Whether to include the link icon</param> /// <returns>System.Drawing.Icon</returns> public static System.Drawing.Icon GetFileIcon(string name, IconSize size, bool linkOverlay) { Shell32.SHFILEINFO shfi = new Shell32.SHFILEINFO(); uint flags = Shell32.SHGFI_ICON | Shell32.SHGFI_USEFILEATTRIBUTES; if(true == linkOverlay) flags |= Shell32.SHGFI_LINKOVERLAY; /* Check the size specified for return. */ if(IconSize.Small == size) { flags |= Shell32.SHGFI_SMALLICON; } else { flags |= Shell32.SHGFI_LARGEICON; } Shell32.SHGetFileInfo(name, Shell32.FILE_ATTRIBUTE_NORMAL, ref shfi, (uint)System.Runtime.InteropServices.Marshal.SizeOf(shfi), flags); // Copy (clone) the returned icon to a new object, thus allowing us to clean-up properly System.Drawing.Icon icon = (System.Drawing.Icon)System.Drawing.Icon.FromHandle(shfi.hIcon).Clone(); User32.DestroyIcon(shfi.hIcon); // Cleanup return icon; } /// <summary> /// Used to access system folder icons. /// </summary> /// <param name="size">Specify large or small icons.</param> /// <param name="folderType">Specify open or closed FolderType.</param> /// <returns>System.Drawing.Icon</returns> public static System.Drawing.Icon GetFolderIcon(string Foldername, IconSize size, FolderType folderType) { // Need to add size check, although errors generated at present! uint flags = Shell32.SHGFI_ICON | Shell32.SHGFI_USEFILEATTRIBUTES; if(FolderType.Open == folderType) { flags |= Shell32.SHGFI_OPENICON; } if(IconSize.Small == size) { flags |= Shell32.SHGFI_SMALLICON; } else { flags |= Shell32.SHGFI_LARGEICON; } // Get the folder icon Shell32.SHFILEINFO shfi = new Shell32.SHFILEINFO(); Shell32.SHGetFileInfo(Foldername, Shell32.FILE_ATTRIBUTE_DIRECTORY, ref shfi, (uint)System.Runtime.InteropServices.Marshal.SizeOf(shfi), flags); System.Drawing.Icon.FromHandle(shfi.hIcon); // Load the icon from an HICON handle // Now clone the icon, so that it can be successfully stored in an ImageList System.Drawing.Icon icon = (System.Drawing.Icon)System.Drawing.Icon.FromHandle(shfi.hIcon).Clone(); User32.DestroyIcon(shfi.hIcon); // Cleanup return icon; } } public class Shell32 { public const int MAX_PATH = 256; [StructLayout(LayoutKind.Sequential)] public struct SHITEMID { public ushort cb; [MarshalAs(UnmanagedType.LPArray)] public byte[] abID; } [StructLayout(LayoutKind.Sequential)] public struct ITEMIDLIST { public SHITEMID mkid; } [StructLayout(LayoutKind.Sequential)] public struct BROWSEINFO { public IntPtr hwndOwner; public IntPtr pidlRoot; public IntPtr pszDisplayName; [MarshalAs(UnmanagedType.LPTStr)] public string lpszTitle; public uint ulFlags; public IntPtr lpfn; public int lParam; public IntPtr iImage; } // Browsing for directory. public const uint BIF_RETURNONLYFSDIRS = 0x0001; public const uint BIF_DONTGOBELOWDOMAIN = 0x0002; public const uint BIF_STATUSTEXT = 0x0004; public const uint BIF_RETURNFSANCESTORS = 0x0008; public const uint BIF_EDITBOX = 0x0010; public const uint BIF_VALIDATE = 0x0020; public const uint BIF_NEWDIALOGSTYLE = 0x0040; public const uint BIF_USENEWUI = (BIF_NEWDIALOGSTYLE | BIF_EDITBOX); public const uint BIF_BROWSEINCLUDEURLS = 0x0080; public const uint BIF_BROWSEFORCOMPUTER = 0x1000; public const uint BIF_BROWSEFORPRINTER = 0x2000; public const uint BIF_BROWSEINCLUDEFILES = 0x4000; public const uint BIF_SHAREABLE = 0x8000; [StructLayout(LayoutKind.Sequential)] public struct SHFILEINFO { public const int NAMESIZE = 80; public IntPtr hIcon; public int iIcon; public uint dwAttributes; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH)] public string szDisplayName; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = NAMESIZE)] public string szTypeName; }; public const uint SHGFI_ICON = 0x000000100; // get icon public const uint SHGFI_DISPLAYNAME = 0x000000200; // get display name public const uint SHGFI_TYPENAME = 0x000000400; // get type name public const uint SHGFI_ATTRIBUTES = 0x000000800; // get attributes public const uint SHGFI_ICONLOCATION = 0x000001000; // get icon location public const uint SHGFI_EXETYPE = 0x000002000; // return exe type public const uint SHGFI_SYSICONINDEX = 0x000004000; // get system icon index public const uint SHGFI_LINKOVERLAY = 0x000008000; // put a link overlay on icon public const uint SHGFI_SELECTED = 0x000010000; // show icon in selected state public const uint SHGFI_ATTR_SPECIFIED = 0x000020000; // get only specified attributes public const uint SHGFI_LARGEICON = 0x000000000; // get large icon public const uint SHGFI_SMALLICON = 0x000000001; // get small icon public const uint SHGFI_OPENICON = 0x000000002; // get open icon public const uint SHGFI_SHELLICONSIZE = 0x000000004; // get shell size icon public const uint SHGFI_PIDL = 0x000000008; // pszPath is a pidl public const uint SHGFI_USEFILEATTRIBUTES = 0x000000010; // use passed dwFileAttribute public const uint SHGFI_ADDOVERLAYS = 0x000000020; // apply the appropriate overlays public const uint SHGFI_OVERLAYINDEX = 0x000000040; // Get the index of the overlay public const uint FILE_ATTRIBUTE_DIRECTORY = 0x00000010; public const uint FILE_ATTRIBUTE_NORMAL = 0x00000080; [DllImport("Shell32.dll")] public static extern IntPtr SHGetFileInfo( string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbFileInfo, uint uFlags ); } public class User32 { /// <summary> /// Provides access to function required to delete handle. This method is used internally /// and is not required to be called separately. /// </summary> /// <param name="hIcon">Pointer to icon handle.</param> /// <returns>N/A</returns> [DllImport("User32.dll")] public static extern int DestroyIcon(IntPtr hIcon); } } </code></pre> ExplorerTreeView.cs : <pre><code>using System; using System.IO; using System.Windows.Forms; using TreeViewTestProject.Utilities; using System.Collections; namespace TreeViewTestProject { public partial class ExplorerTreeView : TreeViewEx { #region ExplorerNodeSorter Class private class ExplorerNodeSorter : IComparer { public int Compare(object x, object y) { TreeNode nx = x as TreeNode; TreeNode ny = y as TreeNode; bool nxDir = (nx.ImageKey == kDirectoryImageKey); bool nyDir = (ny.ImageKey == kDirectoryImageKey); if(nxDir && !nyDir) { return -1; } else if(nyDir && !nxDir) { return 1; } else { return string.Compare(nx.Text, ny.Text); } } } #endregion private const string kDirectoryImageKey = "directory"; private const string kReplacementText = "C43C65D1-D40F-46F0-BC5E-57265322DDFC"; public ExplorerTreeView() { InitializeComponent(); this.BeforeExpand += new TreeViewCancelEventHandler(ExplorerTreeView_BeforeExpand); this.ImageList = m_FileIcons; this.TreeViewNodeSorter = new ExplorerNodeSorter(); this.LabelEdit = true; // Create the root of the tree and populate it PopulateTreeView(@"C:\"); } private void PopulateTreeView(string DirectoryName) { this.BeginUpdate(); string rootDir = DirectoryName; TreeNode rootNode = CreateTreeNode(rootDir); rootNode.Text = rootDir; this.Nodes.Add(rootNode); PopulateDirectory(rootNode); this.EndUpdate(); } private bool PathIsDirectory(string FullPath) { FileAttributes attr = File.GetAttributes(FullPath); return ((attr & FileAttributes.Directory) == FileAttributes.Directory); } private TreeNode CreateTreeNode(string FullPath) { string key = FullPath.ToLower(); string name = ""; object tag = null; if(PathIsDirectory(key)) { DirectoryInfo info = new DirectoryInfo(FullPath); key = kDirectoryImageKey; name = info.Name; tag = info; } else { FileInfo info = new FileInfo(FullPath); name = info.Name; tag = info; } if(!m_FileIcons.Images.ContainsKey(key)) { if(key == "directory") { m_FileIcons.Images.Add(key, IconReader.GetFolderIcon(Environment.CurrentDirectory, IconReader.IconSize.Small, IconReader.FolderType.Open).ToBitmap()); } else { m_FileIcons.Images.Add(key, IconReader.GetFileIcon(FullPath, IconReader.IconSize.Small, false)); } } TreeNode node = new TreeNode(name); node.Tag = tag; node.ImageKey = key; node.SelectedImageKey = key; return node; } private void PopulateDirectory(TreeNode ParentNode) { DirectoryInfo parentInfo = ParentNode.Tag as DirectoryInfo; foreach(DirectoryInfo subDir in parentInfo.GetDirectories()) { TreeNode child = CreateTreeNode(subDir.FullName); PopulateForExpansion(child); ParentNode.Nodes.Add(child); } foreach(FileInfo file in parentInfo.GetFiles()) { ParentNode.Nodes.Add(CreateTreeNode(file.FullName)); } } private void PopulateForExpansion(TreeNode ParentNode) { // We need the +/- to show up if this directory isn't empty... but only want to populate the node on demand DirectoryInfo parentInfo = ParentNode.Tag as DirectoryInfo; try { if((parentInfo.GetDirectories().Length > 0) || (parentInfo.GetFiles().Length > 0)) { ParentNode.Nodes.Add(kReplacementText); } } catch { } } private void ReplacePlaceholderDirectoryNode(TreeNode ParentNode) { if((ParentNode.Nodes.Count == 1) && (ParentNode.Nodes[0].Text == kReplacementText)) { ParentNode.Nodes.Clear(); PopulateDirectory(ParentNode); } } private void ExplorerTreeView_BeforeExpand(object sender, TreeViewCancelEventArgs e) { this.BeginUpdate(); ReplacePlaceholderDirectoryNode(e.Node); this.EndUpdate(); } } } </code></pre> TreeViewEx.cs: <pre><code>using System; using System.Drawing; using System.Drawing.Drawing2D; using System.Runtime.InteropServices; using System.Windows.Forms; namespace TreeViewTestProject { public partial class TreeViewEx : TreeView { // Notes: TextRenderer uses GDI to render the text, whereas Graphics uses GDI+. "TreeView" has existed for a long long time // and thus uses GDI under the covers. For User Drawing TreeNode's, we need to make sure we use the TextRenderer version // of text rendering functions. #region Properties private DashStyle m_SelectionDashStyle = DashStyle.Dot; public DashStyle SelectionDashStyle { get { return m_SelectionDashStyle; } set { m_SelectionDashStyle = value; } } private DashStyle m_LineStyle = DashStyle.Solid; public DashStyle LineStyle { get { return m_LineStyle; } set { m_LineStyle = value; } } private bool m_ShowLines = true; public new bool ShowLines // marked as 'new' to replace base functionality fixing ShowLines/FullRowSelect issues in base. { get { return m_ShowLines; } set { m_ShowLines = value; } } protected override CreateParams CreateParams { get { // Removes all the flickering of repainting node's // This is the only thing I found that works properly for doublebuffering a treeview. CreateParams cp = base.CreateParams; cp.ExStyle |= 0x02000000; // WS_CLIPCHILDREN return cp; } } #endregion [DllImport("user32.dll", ExactSpelling = false, CharSet = CharSet.Auto)] private static extern int GetWindowLong(IntPtr hWnd, int nIndex); [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = false)] private static extern IntPtr SendMessage(HandleRef hWnd, uint Msg, IntPtr wParam, HandleRef lParam); private const int GWL_STYLE = -16; private const int WS_VSCROLL = 0x00200000; private const uint TV_FIRST = 0x1100; private const uint TVM_EDITLABELA = (TV_FIRST + 14); private const uint TVM_EDITLABELW = (TV_FIRST + 65); private bool m_SelectionChanged = false; private bool m_DoubleClicked = false; private bool m_HierarchyChanged = false; public TreeViewEx() { InitializeComponent(); // ShowLines must be "false" for FullRowSelect to work - so we're overriding the variable to correct for that. base.ShowLines = false; this.FullRowSelect = true; this.ItemHeight = 21; this.DrawMode = TreeViewDrawMode.OwnerDrawAll; this.DrawNode += OnDrawNode; } private void OnDrawNode(object sender, DrawTreeNodeEventArgs e) { e.DrawDefault = false; if(e.Node.Bounds.IsEmpty) return; // Clear out the previous contents for the node. If we don't do this, when you mousehover the font will get slightly more bold Rectangle bounds = new Rectangle(0, e.Node.Bounds.Y, this.Width - 1, e.Node.Bounds.Height - 1); e.Graphics.FillRectangle(SystemBrushes.Window, bounds); // Draw everything DrawNodeFocusedHighlight(e); DrawNodeLines(e); DrawPlusMinus(e); DrawNodeIcon(e); DrawNodeText(e); } private void DrawNodeFocusedHighlight(DrawTreeNodeEventArgs e) { if(SelectedNode != e.Node) return; int scrollWidth = 0; if(VScrollVisible()) { scrollWidth = SystemInformation.VerticalScrollBarWidth; } Rectangle bounds = new Rectangle(0, e.Node.Bounds.Y, this.Width - scrollWidth, e.Node.Bounds.Height - 1); if(!e.Node.IsEditing) { e.Graphics.FillRectangle(SystemBrushes.Highlight, bounds); } using(Pen focusPen = new Pen(Color.Black)) { focusPen.DashStyle = SelectionDashStyle; bounds = new Rectangle(0, e.Node.Bounds.Y, this.Width - scrollWidth - 5, e.Node.Bounds.Height - 2); e.Graphics.DrawRectangle(focusPen, bounds); } } private void DrawNodeText(DrawTreeNodeEventArgs e) { if(e.Node.Bounds.IsEmpty) return; if(e.Node.IsEditing) return; Rectangle bounds = e.Node.Bounds; using(Font font = e.Node.NodeFont) { bounds.Width = TextRenderer.MeasureText(e.Node.Text, font).Width; bounds.Y -= 1; bounds.X += 1; if(IsRootNode(e.Node)) { bounds = new Rectangle(this.Margin.Size.Width + Properties.Resources.minus.Width + 9, 0, bounds.Width, bounds.Height); } Color fontColor = SystemColors.InactiveCaptionText; if(this.Focused) { fontColor = e.Node.IsSelected?SystemColors.HighlightText:this.ForeColor; } TextRenderer.DrawText(e.Graphics, e.Node.Text, font, bounds, fontColor); } } private bool IsRootNode(TreeNode Node) { return (Node.Level == 0 && Node.PrevNode == null); } private void DrawNodeLines(DrawTreeNodeEventArgs e) { DrawNodeLineVertical(e); DrawNodeLineHorizontal(e); } private void DrawNodeLineVertical(DrawTreeNodeEventArgs e) { if(IsRootNode(e.Node)) return; if(!ShowLines) return; Pen linePen = new Pen(Color.Black); linePen.DashStyle = LineStyle; for(int x = 0; x < e.Node.Level; x++) { int xLoc = this.Indent + (x * this.Indent) + (Properties.Resources.minus.Width / 2); int height = e.Bounds.Height; if(ShouldDrawVerticalLineForLevel(e.Node, x)) { e.Graphics.DrawLine(linePen, xLoc, e.Bounds.Top, xLoc, e.Bounds.Top + height); } } // Draw the half line for the last node if(e.Node.Parent.LastNode == e.Node) { int halfLoc = (e.Node.Level * this.Indent) + (Properties.Resources.minus.Width / 2); e.Graphics.DrawLine(linePen, halfLoc, e.Bounds.Top, halfLoc, (e.Bounds.Top + e.Bounds.Height / 2) - 1); } } private bool ShouldDrawVerticalLineForLevel(TreeNode Current, int Level) { TreeNode node = Current; TreeNode c = Current; while(node.Level != Level) { c = node; node = node.Parent; } return !(node.LastNode == c); } private void DrawNodeLineHorizontal(DrawTreeNodeEventArgs e) { if(IsRootNode(e.Node)) return; if(!ShowLines) return; Pen linePen = new Pen(Color.Black); int xLoc = (e.Node.Level * this.Indent) + (Properties.Resources.minus.Width / 2); int midY = (e.Bounds.Top + e.Bounds.Bottom) / 2 - 1; e.Graphics.DrawLine(linePen, xLoc, midY, xLoc + 7, midY); } private void DrawNodeIcon(DrawTreeNodeEventArgs e) { if(this.ImageList == null) return; int indent = (e.Node.Level * this.Indent) + this.Margin.Size.Width; int iconLeft = indent + this.Indent; int imgIndex = this.ImageList.Images.IndexOfKey(e.Node.ImageKey); if(!IsRootNode(e.Node)) { if(imgIndex >= 0) { Image img = this.ImageList.Images[imgIndex]; int y = (e.Bounds.Y + e.Bounds.Height / 2) - (img.Height / 2) - 1; e.Graphics.DrawImage(img, new Rectangle(iconLeft, y, img.Width, img.Height), new Rectangle(0, 0, img.Width, img.Height), GraphicsUnit.Pixel); } } } private void DrawPlusMinus(DrawTreeNodeEventArgs e) { if(e.Node.Nodes.Count == 0) return; int indent = (e.Node.Level * this.Indent) + this.Margin.Size.Width; int iconLeft = indent + this.Indent; Image img = Properties.Resources.plus; if(e.Node.IsExpanded) img = Properties.Resources.minus; e.Graphics.DrawImage(img, iconLeft - img.Width - 2, (e.Bounds.Y + e.Bounds.Height / 2) - (img.Height / 2) - 1); } private bool VScrollVisible() { int style = GetWindowLong(this.Handle, GWL_STYLE); return ((style & WS_VSCROLL) != 0); } private void BeginEditNode() { if(this.SelectedNode == null) return; if(!this.LabelEdit) throw new Exception("This TreeView is not configured with LabelEdit=true"); IntPtr result = SendMessage(new HandleRef(this, this.Handle), TVM_EDITLABELA, IntPtr.Zero, new HandleRef(this.SelectedNode, this.SelectedNode.Handle)); if(result == IntPtr.Zero) { throw new Exception("Failed to send EDITLABEL message to TreeView control."); } } private void TreeViewEx_BeforeLabelEdit(object sender, NodeLabelEditEventArgs e) { if(m_DoubleClicked) { m_DoubleClicked = false; return; } if(m_SelectionChanged) { e.CancelEdit = true; m_SelectionChanged = false; } } private void TreeViewEx_MouseDoubleClick(object sender, MouseEventArgs e) { if(m_HierarchyChanged) { m_HierarchyChanged = false; return; } if((e.Button & MouseButtons.Left) > 0) { if(this.LabelEdit && (this.SelectedNode != null)) { m_DoubleClicked = true; BeginInvoke(new MethodInvoker(delegate() { this.SelectedNode.BeginEdit(); })); } } } private void TreeViewEx_AfterCollapse(object sender, TreeViewEventArgs e) { m_HierarchyChanged = true; } private void TreeViewEx_AfterExpand(object sender, TreeViewEventArgs e) { m_HierarchyChanged = true; } } } </code></pre>
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