ready for testing

ObservatoryCore/UI/PluginListView.cs

@@ -0,0 +1,113 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Security.Permissions;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Observatory.UI
+{
+    internal class PluginListView : ListView
+    {
+        [DllImport("user32.dll")]
+        private static extern int SendMessage(IntPtr hWnd, int wMsg, bool wParam, int lParam);
+        
+        private const int WM_SETREDRAW = 11;
+
+        public PluginListView()
+        {
+            OwnerDraw = true;
+            GridLines = false;
+            DrawItem += PluginListView_DrawItem;
+            DrawSubItem += PluginListView_DrawSubItem;
+            DrawColumnHeader += PluginListView_DrawColumnHeader;
+            
+            
+            DoubleBuffered = true;
+            base.GridLines = false;//We should prevent the default drawing of gridlines.
+        }
+
+        private static void DrawBorder(Graphics graphics, Pen pen, Rectangle bounds, bool header = false)
+        {
+            
+            Point topRight = new(bounds.Right, bounds.Top);
+            Point bottomRight = new(bounds.Right, bounds.Bottom);
+            
+            graphics.DrawLine(pen, topRight, bottomRight);
+            
+            if (header)
+            {
+                Point bottomLeft = new(bounds.Left, bounds.Bottom);
+                // Point topLeft = new(bounds.Left, bounds.Top);
+                // graphics.DrawLine(pen, topLeft, topRight);
+                // graphics.DrawLine(pen, topLeft, bottomLeft);
+                graphics.DrawLine(pen, bottomLeft, bottomRight);
+            }
+        }
+
+        private void PluginListView_DrawColumnHeader(object? sender, DrawListViewColumnHeaderEventArgs e)
+        {
+            using (var g = e.Graphics)
+                if (g != null)
+                {
+                    g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
+                    Pen pen = new(new SolidBrush(Color.LightGray));
+                    DrawBorder(g, pen, e.Bounds);
+                    using (var font = new Font(this.Font, FontStyle.Bold))
+                    {
+                        Brush textBrush = new SolidBrush(ForeColor);
+                        g.DrawString(e.Header?.Text, font, textBrush, e.Bounds);
+                    }
+                }
+        }
+
+        private void PluginListView_DrawSubItem(object? sender, DrawListViewSubItemEventArgs e)
+        {
+            using (var g = e.Graphics)
+                if (g != null)
+                {
+                    g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
+                    Pen pen = new(new SolidBrush(Color.LightGray));
+                    DrawBorder(g, pen, e.Bounds, false);
+                    
+                    e.DrawText();
+                }
+        }
+
+        private void PluginListView_DrawItem(object? sender, DrawListViewItemEventArgs e)
+        {
+            var offsetColor = (int value) =>
+            {
+                if (value > 127)
+                {
+                    return value - 20;
+                }
+                else
+                {
+                    return value + 20;
+                }
+            };
+
+            using (var g = e.Graphics)
+            {
+                if (e.ItemIndex % 2 == 0)
+                {
+                    e.Item.BackColor = BackColor;
+                }
+                else
+                {
+                    e.Item.BackColor = Color.FromArgb(offsetColor(BackColor.R), offsetColor(BackColor.G), offsetColor(BackColor.B));
+                }
+
+                if (g != null)
+                {
+                    g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
+                    Pen pen = new(new SolidBrush(Color.LightGray));
+                    e.DrawBackground();
+                }
+            }
+   
+        }
+    }
+}