Recalculate the node position of the TreeView when DrawMode = TreeViewDrawMode.OwnerDrawText

Author: LeafShi1

src/System.Windows.Forms/src/System/Windows/Forms/Controls/TreeView/TreeView.cs

@@ -7,6 +7,7 @@
 using System.Drawing.Design;
 using System.Runtime.InteropServices;
 using System.Windows.Forms.Layout;
+using System.Windows.Forms.Primitives;
 using System.Windows.Forms.VisualStyles;
 using Windows.Win32.System.Variant;
 using Windows.Win32.UI.Accessibility;
@@ -2734,6 +2735,13 @@ private unsafe void CustomDraw(ref Message m)
                 // as background color.
                 if (_drawMode == TreeViewDrawMode.OwnerDrawText)
                 {
+                    if (node is { IsEditing: true })
+                    {
+                        nmtvcd->clrText = ColorTranslator.ToWin32(BackColor);
+                        nmtvcd->clrTextBk = ColorTranslator.ToWin32(BackColor);
+                        goto default;
+                    }
+
                     nmtvcd->clrText = nmtvcd->clrTextBk;
                     m.ResultInternal = (LRESULT)(nint)(PInvoke.CDRF_NEWFONT | PInvoke.CDRF_NOTIFYPOSTPAINT);
                     return;
@@ -2792,6 +2800,11 @@ private unsafe void CustomDraw(ref Message m)
                     nmtvcd->clrTextBk = ColorTranslator.ToWin32(riBack);
                 }
 
+                if (node is { IsEditing: true })
+                {
+                    nmtvcd->clrTextBk = ColorTranslator.ToWin32(BackColor);
+                }
+
                 if (renderinfo is not null && renderinfo.Font is not null)
                 {
                     // Mess with the DC directly...
@@ -2826,8 +2839,36 @@ private unsafe void CustomDraw(ref Message m)
                     {
                         Rectangle bounds = node.Bounds;
                         Size textSize = TextRenderer.MeasureText(node.Text, node.TreeView!.Font);
-                        Point textLoc = new(AppContextSwitches.MoveTreeViewTextLocationOnePixel ? bounds.X : bounds.X - 1, bounds.Y);
-                        bounds = new Rectangle(textLoc, new Size(textSize.Width, bounds.Height));
+                        Point textLocation = new(AppContextSwitches.MoveTreeViewTextLocationOnePixel ? bounds.X : bounds.X - 1, bounds.Y);
+                        bounds = new Rectangle(textLocation, new Size(textSize.Width, bounds.Height));
+
+                        Rectangle fillRectangle = new Rectangle(textLocation, new(textSize.Width, bounds.Height));
+                        Rectangle focusRectangle = new Rectangle(textLocation, new(textSize.Width, bounds.Height));
+
+                        if (RightToLeft == RightToLeft.Yes && RightToLeftLayout)
+                        {
+                            int borderWidth = BorderStyle switch
+                            {
+                                BorderStyle.FixedSingle => 1,
+                                BorderStyle.Fixed3D => 2,
+                                _ => 0
+                            };
+
+                            // Reverse the X-axis drawing coordinates of the rectangle.
+                            int invertedX = Width - bounds.X - textSize.Width - borderWidth * 2;
+
+                            // Subtract the scroll bar width when the scroll bar appears.
+                            if (Height - borderWidth * 2 < PreferredHeight)
+                            {
+                                float dpiScale = (float)DeviceDpi / (float)ScaleHelper.InitialSystemDpi;
+                                invertedX -= (int)(SystemInformation.VerticalScrollBarWidth * Math.Round(dpiScale, 2));
+                            }
+
+                            // To ensure that the right side of the fillRectangle does not
+                            // touch the left edge of the node prefix symbol, 1 pixel is subtracted here.
+                            fillRectangle = new Rectangle(new Point(invertedX - 1, bounds.Y), new(textSize.Width, bounds.Height));
+                            focusRectangle = new Rectangle(new Point(invertedX, bounds.Y), new(textSize.Width, bounds.Height));
+                        }
 
                         DrawTreeNodeEventArgs e = new(g, node, bounds, (TreeNodeStates)(nmtvcd->nmcd.uItemState));
                         OnDrawNode(e);
@@ -2843,14 +2884,14 @@ private unsafe void CustomDraw(ref Message m)
                             // Draw the actual node.
                             if ((curState & TreeNodeStates.Selected) == TreeNodeStates.Selected)
                             {
-                                g.FillRectangle(SystemBrushes.Highlight, bounds);
-                                ControlPaint.DrawFocusRectangle(g, bounds, color, SystemColors.Highlight);
+                                g.FillRectangle(SystemBrushes.Highlight, fillRectangle);
+                                ControlPaint.DrawFocusRectangle(g, focusRectangle, color, SystemColors.Highlight);
                                 TextRenderer.DrawText(g, node.Text, font, bounds, color, TextFormatFlags.Default);
                             }
                             else
                             {
                                 using var brush = BackColor.GetCachedSolidBrushScope();
-                                g.FillRectangle(brush, bounds);
+                                g.FillRectangle(brush, fillRectangle);
 
                                 TextRenderer.DrawText(g, node.Text, font, bounds, color, TextFormatFlags.Default);
                             }
@@ -2870,6 +2911,35 @@ private unsafe void CustomDraw(ref Message m)
         }
     }
 
+    private int PreferredHeight
+    {
+        get
+        {
+            int height = 0;
+            foreach (TreeNode node in Nodes)
+            {
+                height += GetNodeHeight(node);
+            }
+
+            return height;
+        }
+    }
+
+    private int GetNodeHeight(TreeNode node)
+    {
+        int height = ItemHeight;
+
+        if (node.IsExpanded)
+        {
+            foreach (TreeNode childNode in node.Nodes)
+            {
+                height += GetNodeHeight(childNode);
+            }
+        }
+
+        return height;
+    }
+
     /// <summary>
     ///  Generates colors for each item. This can be overridden to provide colors on a per state/per node
     ///  basis, rather than using the ForeColor/BackColor/NodeFont properties on TreeNode.