This PR fixes some bugs, and adds some nice-to-have features

.gitignore

@@ -13,6 +13,9 @@ TestResults
 *.user
 *.sln.docstates
 
+# Visual Studio 2015/2017 cache/options directory
+.vs/
+
 # Build results
 [Dd]ebug/
 [Rr]elease/

FastColoredTextBox/AutocompleteMenu.cs

@@ -4,6 +4,8 @@
 using System.Drawing;
 using System.ComponentModel;
 using System.Drawing.Drawing2D;
+using System.Reflection;
+using System.Runtime.InteropServices;
 using System.Text.RegularExpressions;
 
 namespace FastColoredTextBoxNS
@@ -79,7 +81,7 @@ public AutocompleteMenu(FastColoredTextBox tb)
         {
             // create a new popup and add the list view to it 
             AutoClose = false;
-            AutoSize = false;
+            AutoSize = true;
             Margin = Padding.Empty;
             Padding = Padding.Empty;
             BackColor = Color.White;
@@ -223,10 +225,60 @@ private int ItemHeight
         System.Windows.Forms.Timer timer = new System.Windows.Forms.Timer();
 
         internal bool AllowTabKey { get; set; }
+
+        /// <summary>
+        /// Make the menu fit to width of shown items.
+        /// </summary>
+        private bool _autoWidth;
+        public bool AutoWidth
+        {
+            get => _autoWidth;
+            set
+            {
+                _autoWidth = value;
+                MaximumSize = new Size(_autoWidth ? 1000 : Size.Width, MaximumSize.Height);
+            }
+        }
+
+        /// <summary>
+        /// If AutoWidth is true, this property specifies extra padding on the right of menu items. Default is 10. Note: AutoWidth should be true to use this property.
+        /// </summary>
+        public int AutoWidthExtraPadding { get; set; } = 10;
+
+        /// <summary>
+        /// Set to true to remove the padding for icons on the left of the menu
+        /// </summary>
+        public bool NoSpacingForIcons { get; set; }
+        /// <summary>
+        /// Set to true to use solid brush for selected item. Default is a linear gradient from SelectedColor to a transparent.
+        /// </summary>
+        public bool UseSolidBrushForSelected { get; set; }
+        /// <summary>
+        /// Set to true to show menu again after an item is selected.
+        /// </summary>
+        public bool ReShowMenuAfterSelected { get; set; }
+        /// <summary>
+        /// Set to false to disable wrapping up/down navigation. If false, user can't navigate from last item to first and back. Default is true.
+        /// </summary>
+        public bool DisableWrappingUpDownNavigation { get; set; }
         public ImageList ImageList { get; set; }
         internal int AppearInterval { get { return timer.Interval; } set { timer.Interval = value; } }
+        /// <summary>
+        /// The duration of tooltip showing in milliseconds. Set to 0 to show tooltip indefinitely.
+        /// </summary>
         internal int ToolTipDuration { get; set; }
-        internal Size MaxToolTipSize { get; set; }
+
+        private Size maxToolTipSize;
+        internal Size MaxToolTipSize
+        {
+            get => maxToolTipSize;
+            set
+            {
+                maxToolTipSize = value;
+                SetTooltipMaxWidth();
+            }
+        }
+
         internal bool AlwaysShowTooltip
         {
             get { return toolTip.ShowAlways; }
@@ -309,10 +361,23 @@ internal AutocompleteListView(FastColoredTextBox tb)
             };
         }
 
+        private const uint TTM_SETMAXTIPWIDTH = 0x418;
+        [DllImport("user32.dll")]
+        private static extern int SendMessage(IntPtr hwnd, uint msg,
+            int wParam, int lParam);
+        private void SetTooltipMaxWidth()
+        {
+            var o = typeof(ToolTip).InvokeMember("Handle",
+                BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.GetProperty,
+                null, toolTip, null);
+            var hwnd = (IntPtr)o;
+            SendMessage(hwnd, TTM_SETMAXTIPWIDTH, 0, MaxToolTipSize.Width);
+        }
+
         private void ToolTip_Popup(object sender, PopupEventArgs e)
         {
-            if (MaxToolTipSize.Height > 0 && MaxToolTipSize.Width > 0)
-                e.ToolTipSize = MaxToolTipSize;
+            if (MaxToolTipSize.Height > 0)
+                e.ToolTipSize = new Size(e.ToolTipSize.Width, Math.Min(e.ToolTipSize.Height, MaxToolTipSize.Height));
         }
 
         protected override void Dispose(bool disposing)
@@ -387,6 +452,7 @@ internal void DoAutocomplete(bool forced)
             visibleItems.Clear();
             FocussedItemIndex = 0;
             VerticalScroll.Value = 0;
+            biggestTextWidth = 0;
             //some magic for update scrolls
             AutoScrollMinSize -= new Size(1, 0);
             AutoScrollMinSize += new Size(1, 0);
@@ -513,6 +579,8 @@ void AdjustScroll()
             oldItemCount = visibleItems.Count;
         }
 
+        private int biggestTextWidth;
+        private bool widthChanged;
         protected override void OnPaint(PaintEventArgs e)
         {
             AdjustScroll();
@@ -523,34 +591,52 @@ protected override void OnPaint(PaintEventArgs e)
             startI = Math.Max(startI, 0);
             finishI = Math.Min(finishI, visibleItems.Count);
             int y = 0;
-            int leftPadding = 18;
+            int leftPadding = NoSpacingForIcons ? 0 : 18;
             for (int i = startI; i < finishI; i++)
             {
                 y = i * itemHeight - VerticalScroll.Value;
 
                 var item = visibleItems[i];
 
                 if(item.BackColor != Color.Transparent)
-                using (var brush = new SolidBrush(item.BackColor))
-                    e.Graphics.FillRectangle(brush, 1, y, ClientSize.Width - 1 - 1, itemHeight - 1);
+                    using (var brush = new SolidBrush(item.BackColor))
+                        e.Graphics.FillRectangle(brush, 1, y, ClientSize.Width - 1 - 1, itemHeight - 1);
 
                 if (ImageList != null && visibleItems[i].ImageIndex >= 0)
                     e.Graphics.DrawImage(ImageList.Images[item.ImageIndex], 1, y);
 
                 if (i == FocussedItemIndex)
-                using (var selectedBrush = new LinearGradientBrush(new Point(0, y - 3), new Point(0, y + itemHeight), Color.Transparent, SelectedColor))
-                using (var pen = new Pen(SelectedColor))
-                {
-                    e.Graphics.FillRectangle(selectedBrush, leftPadding, y, ClientSize.Width - 1 - leftPadding, itemHeight - 1);
-                    e.Graphics.DrawRectangle(pen, leftPadding, y, ClientSize.Width - 1 - leftPadding, itemHeight - 1);
-                }
+                    using (var selectedBrush = UseSolidBrushForSelected ? (Brush)new SolidBrush(SelectedColor) 
+                               : new LinearGradientBrush(new Point(0, y - 3), new Point(0, y + itemHeight), Color.Transparent, SelectedColor))
+                    using (var pen = new Pen(SelectedColor))
+                    {
+                        e.Graphics.FillRectangle(selectedBrush, leftPadding, y, ClientSize.Width - 1 - leftPadding, itemHeight - 1);
+                        e.Graphics.DrawRectangle(pen, leftPadding, y, ClientSize.Width - 1 - leftPadding, itemHeight - 1);
+                    }
 
                 if (i == hoveredItemIndex)
-                using(var pen = new Pen(HoveredColor))
-                    e.Graphics.DrawRectangle(pen, leftPadding, y, ClientSize.Width - 1 - leftPadding, itemHeight - 1);
+                    using(var pen = new Pen(HoveredColor))
+                        e.Graphics.DrawRectangle(pen, leftPadding, y, ClientSize.Width - 1 - leftPadding, itemHeight - 1);
 
                 using (var brush = new SolidBrush(item.ForeColor != Color.Transparent ? item.ForeColor : ForeColor))
                     e.Graphics.DrawString(item.ToString(), Font, brush, leftPadding, y);
+
+                if (!AutoWidth) continue;
+                var textSize = e.Graphics.MeasureString(item.ToString(), Font, new SizeF(500, 500));
+                if ((int)textSize.Width > biggestTextWidth)
+                {
+                    biggestTextWidth = (int)textSize.Width;
+                    widthChanged = true;
+                }
+            }
+
+            if (!widthChanged) return;
+            widthChanged = false;
+            Width = leftPadding + biggestTextWidth + AutoWidthExtraPadding + (VScroll ? SystemInformation.VerticalScrollBarWidth : 0);
+            if(toBeUsedInOnPaint != null)
+            {
+                SetToolTip(toBeUsedInOnPaint); //Adjust tooltip position after width change
+                toBeUsedInOnPaint = null;
             }
         }
 
@@ -610,6 +696,7 @@ internal virtual void OnSelecting()
                 }
 
                 Menu.Close();
+                if(ReShowMenuAfterSelected) ResetTimer(timer);
                 //
                 SelectedEventArgs args2 = new SelectedEventArgs()
                 {
@@ -701,7 +788,17 @@ private bool ProcessKey(Keys keyData, Keys keyModifiers)
 
         public void SelectNext(int shift)
         {
-            FocussedItemIndex = Math.Max(0, Math.Min(FocussedItemIndex + shift, visibleItems.Count - 1));
+            if (DisableWrappingUpDownNavigation)
+            {
+                FocussedItemIndex = Math.Max(0, Math.Min(FocussedItemIndex + shift, visibleItems.Count - 1));
+            }
+            else
+            {
+                var newIndex = FocussedItemIndex + shift;
+                if (newIndex < 0) newIndex = visibleItems.Count - 1;
+                else if (newIndex >= visibleItems.Count) newIndex = 0;
+                FocussedItemIndex = newIndex;
+            }
             DoSelectedVisible();
             //
             Invalidate();
@@ -722,15 +819,17 @@ private void DoSelectedVisible()
             AutoScrollMinSize += new Size(1, 0);
         }
 
+        private AutocompleteItem toBeUsedInOnPaint;
+
         private void SetToolTip(AutocompleteItem autocompleteItem)
         {
             var title = autocompleteItem.ToolTipTitle;
             var text = autocompleteItem.ToolTipText;
 
             if (string.IsNullOrEmpty(title))
             {
-                toolTip.ToolTipTitle = null;
-                toolTip.SetToolTip(this, null);
+                toolTip.Hide(Parent ?? this);
+                toBeUsedInOnPaint = null;
                 return;
             }
 
@@ -743,16 +842,19 @@ private void SetToolTip(AutocompleteItem autocompleteItem)
                     location = new Point(Right + 5, 0);
                 else
                     location = new Point(Left - 105 - MaximumSize.Width, 0);
+                toBeUsedInOnPaint = autocompleteItem;
 
                 if (string.IsNullOrEmpty(text))
                 {
                     toolTip.ToolTipTitle = null;
-                    toolTip.Show(title, window, location.X, location.Y, ToolTipDuration);
+                    if(ToolTipDuration > 0) toolTip.Show(title, window, location.X, location.Y, ToolTipDuration);
+                    else toolTip.Show(title, window, location.X, location.Y);
                 }
                 else
                 {
                     toolTip.ToolTipTitle = title;
-                    toolTip.Show(text, window, location.X, location.Y, ToolTipDuration);
+                    if(ToolTipDuration > 0) toolTip.Show(text, window, location.X, location.Y, ToolTipDuration);
+                    else toolTip.Show(text, window, location.X, location.Y);
                 }
             }
         }