Improve & use the new FlagsEditor for all flags

Turns out Scintilla had a custom editor for flags called `FlagsEnumConverter` before. Unaware of the first one, I wrote a new one called `FlagsEditor` for `ChangeHistory` enum. I may be biased but it turned out pretty good so I think it would be cool to use it for all flags.

Scintilla.NET/FlagsConverter.cs

@@ -0,0 +1,75 @@
+using System;
+using System.ComponentModel;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+
+namespace ScintillaNET;
+
+internal class FlagsConverter : TypeConverter
+{
+    public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
+    {
+        return destinationType == typeof(string) || base.CanConvertTo(context, destinationType);
+    }
+
+    public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
+    {
+        return sourceType == typeof(string) || base.CanConvertFrom(context, sourceType);
+    }
+
+    public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
+    {
+        if (value is Enum valueEnum && destinationType == typeof(string))
+        {
+            Type enumType = valueEnum.GetType();
+            ulong valueBits = Convert.ToUInt64(valueEnum);
+            if (valueBits == 0)
+            {
+                return Enum.ToObject(enumType, 0).ToString();
+            }
+            ulong bits = 0;
+            StringBuilder sb = new StringBuilder();
+            void Add(Enum item, ulong itemBits)
+            {
+                if (itemBits != 0 && valueEnum.HasFlag(item))
+                {
+                    bits |= itemBits;
+                    if (sb.Length > 0)
+                        sb.Append(" | ");
+                    sb.Append(item);
+                }
+            }
+            foreach (Enum item in Enum.GetValues(enumType))
+            {
+                ulong itemBits = Convert.ToUInt64(item);
+                if (Helpers.PopCount(itemBits) == 1)
+                    Add(item, itemBits);
+            }
+            foreach (Enum item in Enum.GetValues(enumType))
+            {
+                ulong itemBits = Convert.ToUInt64(item);
+                if (Helpers.PopCount(itemBits) > 1 && (bits & itemBits) != itemBits)
+                    Add(item, itemBits);
+            }
+            return sb.ToString();
+        }
+        return base.ConvertTo(context, culture, value, destinationType);
+    }
+
+    public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
+    {
+        if (value is string str)
+        {
+            Type t = context.PropertyDescriptor.PropertyType;
+            ulong bits = 0;
+            var nameList = str.Split('|').Select(x => x.Trim());
+            foreach (var name in nameList)
+            {
+                bits |= Convert.ToUInt64(Enum.Parse(t, name));
+            }
+            return Enum.ToObject(t, bits);
+        }
+        return base.ConvertFrom(context, culture, value);
+    }
+}

Scintilla.NET/FlagsEditor.cs

@@ -1,156 +1,26 @@
 using System;
-using System.Collections;
-using System.Collections.Generic;
 using System.ComponentModel;
 using System.Drawing.Design;
-using System.Globalization;
 using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-using System.Windows.Forms;
 using System.Windows.Forms.Design;
 
 namespace ScintillaNET;
 
-internal class FlagsConverter : TypeConverter
-{
-    public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
-    {
-        return destinationType == typeof(string) || base.CanConvertTo(context, destinationType);
-    }
-
-    public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
-    {
-        return sourceType == typeof(string) || base.CanConvertFrom(context, sourceType);
-    }
-
-    public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
-    {
-        if (value is Enum e && destinationType == typeof(string))
-        {
-            if (Convert.ToUInt64(e) == 0)
-            {
-                return Enum.ToObject(e.GetType(), 0).ToString();
-            }
-            StringBuilder sb = new StringBuilder();
-            foreach (Enum item in Enum.GetValues(e.GetType()))
-            {
-                if (Convert.ToUInt64(item) != 0 && e.HasFlag(item))
-                {
-                    if (sb.Length > 0)
-                        sb.Append(" | ");
-                    sb.Append(item);
-                }
-            }
-            return sb.ToString();
-        }
-        return base.ConvertTo(context, culture, value, destinationType);
-    }
-
-    public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
-    {
-        if (value is string str)
-        {
-            Type t = context.PropertyDescriptor.PropertyType;
-            ulong bits = 0;
-            var nameList = str.Split('|').Select(x => x.Trim());
-            foreach (var name in nameList)
-            {
-                bits |= Convert.ToUInt64(Enum.Parse(t, name));
-            }
-            return Enum.ToObject(t, bits);
-        }
-        return base.ConvertFrom(context, culture, value);
-    }
-}
-
 internal class FlagsEditor : UITypeEditor
 {
     public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context) => UITypeEditorEditStyle.DropDown;
 
     public override bool IsDropDownResizable => true;
 
-    private int inCheck = 0;
-
-    private static ulong CombineEnumList(IEnumerable checkedList)
-    {
-        ulong bits = 0;
-        foreach (var item in checkedList)
-        {
-            bits |= Convert.ToUInt64(item);
-        }
-        return bits;
-    }
-
     public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
     {
         if (value is Enum e && context.PropertyDescriptor.Attributes.OfType<FlagsAttribute>().Any())
         {
             IWindowsFormsEditorService svc = (IWindowsFormsEditorService)provider.GetService(typeof(IWindowsFormsEditorService));
-            Type enumType = e.GetType();
 
-            CheckedListBox checkedListBox = new() {
-                Dock = DockStyle.Fill,
-                CheckOnClick = true,
-            };
-            checkedListBox.ItemCheck += (object sender, ItemCheckEventArgs e) => {
-                if (inCheck > 0)
-                    return;
-                inCheck++;
-                try
-                {
-                    ulong bits = CombineEnumList(checkedListBox.CheckedItems);
-                    ulong change = Convert.ToUInt64(checkedListBox.Items[e.Index]);
-                    if (e.NewValue == CheckState.Checked)
-                        bits |= change;
-                    else if (e.NewValue == CheckState.Unchecked)
-                        bits &= ~change;
-                    Enum enumFinal = (Enum)Enum.ToObject(enumType, bits);
-                    for (int i = 0; i < checkedListBox.Items.Count; i++)
-                    {
-                        Enum itemValue = (Enum)checkedListBox.Items[i];
-                        checkedListBox.SetItemChecked(i, enumFinal.HasFlag(itemValue));
-                    }
-                }
-                finally
-                {
-                    inCheck--;
-                }
-            };
-            inCheck++;
-            try
-            {
-                foreach (Enum item in Enum.GetValues(enumType))
-                {
-                    if (Convert.ToUInt64(item) != 0)
-                        checkedListBox.Items.Add(item, e.HasFlag(item));
-                }
-            }
-            finally
-            {
-                inCheck--;
-            }
-            Button okBtton = new() {
-                Dock = DockStyle.Bottom,
-                AutoSize = true,
-                AutoSizeMode = AutoSizeMode.GrowAndShrink,
-                UseVisualStyleBackColor = true,
-            };
-            UserControl userControl = new();
-            userControl.Controls.Add(checkedListBox);
-            userControl.Controls.Add(okBtton);
-            okBtton.Text = NativeMethods.GetMessageBoxString(0); // OK
-            okBtton.Click += (object sender, EventArgs e) => {
-                ulong bits = 0;
-                foreach (Enum item in checkedListBox.CheckedItems)
-                {
-                    bits |= Convert.ToUInt64(item);
-                }
-                value = Enum.ToObject(enumType, bits);
-                svc.CloseDropDown();
-            };
-            svc.DropDownControl(userControl);
-            return value;
+            var control = new FlagsEditorControl(svc, e);
+            svc.DropDownControl(control);
+            return control.Value;
         }
         else
             return base.EditValue(context, provider, value);