Added a custom colour picker

LibSidWiz/Channel.cs

@@ -268,6 +268,8 @@ public int TriggerLookaheadOnFailureFrames
 
         [Category("Appearance")]
         [Description("The line colour")]
+        [Editor(typeof(MyColorEditor), typeof(UITypeEditor))]
+        [TypeConverter(typeof(MyColorConverter))]
         public Color LineColor
         {
             get => _lineColor;
@@ -292,6 +294,8 @@ public float LineWidth
 
         [Category("Appearance")]
         [Description("The fill colour. Set to transparent to have no fill.")]
+        [Editor(typeof(MyColorEditor), typeof(UITypeEditor))]
+        [TypeConverter(typeof(MyColorConverter))]
         public Color FillColor
         {
             get => _fillColor;
@@ -340,6 +344,8 @@ public float ZeroLineWidth
 
         [Category("Appearance")]
         [Description("The color of the zero line")]
+        [Editor(typeof(MyColorEditor), typeof(UITypeEditor))]
+        [TypeConverter(typeof(MyColorConverter))]
         public Color ZeroLineColor
         {
             get => _zeroLineColor;
@@ -352,6 +358,8 @@ public Color ZeroLineColor
 
         [Category("Appearance")]
         [Description("The color of the border")]
+        [Editor(typeof(MyColorEditor), typeof(UITypeEditor))]
+        [TypeConverter(typeof(MyColorConverter))]
         public Color BorderColor
         {
             get => _borderColor;
@@ -388,6 +396,8 @@ public bool BorderEdges
 
         [Category("Appearance")]
         [Description("A background colour for the channel. This is layered above any background image, and can be transparent.")]
+        [Editor(typeof(MyColorEditor), typeof(UITypeEditor))]
+        [TypeConverter(typeof(MyColorConverter))]
         public Color BackgroundColor
         {
             get => _backgroundColor;
@@ -425,6 +435,8 @@ public Font LabelFont
 
         [Category("Appearance")]
         [Description("The color for the channel label")]
+        [Editor(typeof(MyColorEditor), typeof(UITypeEditor))]
+        [TypeConverter(typeof(MyColorConverter))]
         public Color LabelColor
         {
             get => _labelColor;

LibSidWiz/LibSidWiz.csproj

@@ -14,6 +14,7 @@
     <Reference Include="System.Design" />
   </ItemGroup>
   <ItemGroup>
+    <PackageReference Include="Cyotek.Windows.Forms.ColorPicker" Version="1.7.2" />
     <PackageReference Include="NAudio" Version="2.2.1" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
     <PackageReference Include="SkiaSharp" Version="2.88.8" />

LibSidWiz/MyColorConverter.cs

@@ -0,0 +1,15 @@
+using System.ComponentModel;
+using System.Drawing;
+
+namespace LibSidWiz;
+
+/// <summary>
+/// This overrides ColorConverter which interferes with the colour editor.
+/// </summary>
+public class MyColorConverter : ColorConverter
+{
+    public override bool GetStandardValuesSupported(ITypeDescriptorContext context)
+    {
+        return false;
+    }
+}

LibSidWiz/MyColorEditor.cs

@@ -0,0 +1,68 @@
+using System;
+using System.ComponentModel;
+using System.Drawing;
+using System.Drawing.Design;
+using System.Windows.Forms;
+using System.Windows.Forms.Design;
+
+namespace LibSidWiz;
+
+/// <summary>
+/// This allows us to implement a custom colour picker
+/// </summary>
+public class MyColorEditor : UITypeEditor
+{
+    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
+    {
+        return UITypeEditorEditStyle.Modal;
+    }
+
+    public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
+    {
+        if (value is not Color c || provider == null)
+        {
+            return value;
+        }
+
+        var svc = (IWindowsFormsEditorService)provider.GetService(typeof(IWindowsFormsEditorService));
+
+        if (svc == null)
+        {
+            return c;
+        }
+
+        using var form = new Cyotek.Windows.Forms.ColorPickerDialog();
+        form.Color = c;
+        form.ShowAlphaChannel = true;
+        return svc.ShowDialog(form) == DialogResult.OK ? form.Color : c;
+    }
+
+    public override bool GetPaintValueSupported(ITypeDescriptorContext context)
+    {
+        return true;
+    }
+
+    public override void PaintValue(PaintValueEventArgs e)
+    {
+        // This is just for the little rectangle on the left
+        // TODO: indicate transparency?
+        var color = (Color)e.Value;
+        if (color.A < 255)
+        {
+            // Draw a checkerboard of 4x4 using the system colours
+            e.Graphics.FillRectangle(SystemBrushes.Window, e.Bounds);
+            for (var x = 0; x < e.Bounds.Width; x += 4)
+            for (var y = 0; y < e.Bounds.Height; y += 4)
+                if (((x/4 ^ y/4) & 1) == 0)
+                {
+                    e.Graphics.FillRectangle(SystemBrushes.WindowText, x, y, 4, 4);
+                }
+        }
+        using (var brush = new SolidBrush(color))
+        {
+            e.Graphics.FillRectangle(brush, e.Bounds);
+        }
+
+        e.Graphics.DrawRectangle(SystemPens.WindowText, e.Bounds);
+    }
+}