A Managed C++ Wrapper Around the Windows XP Theme API

//  � Copyright 2002, Pierre ARNAUD, OPaC bright ideas, Switzerland.
//    All rights reserved.
using System.Drawing;

using System.Windows.Forms.Themes;

namespace OPaC.Themed.Forms
{
	public class CheckBox : System.Windows.Forms.CheckBox
	{
		private WindowTheme m_WindowTheme = null;

		public CheckBox()
		{
			this.BackColor = System.Drawing.Color.Transparent;
			this.FlatStyle = System.Windows.Forms.FlatStyle.Standard;

			ThemeInfo t = new ThemeInfo();
			if ( t.Count > 0 )
			{
				m_WindowTheme = t["BUTTON"];
			}
		}
		
		public bool									UseTheme
		{
			get
			{
				return UxTheme.IsAppThemed () && !this.DesignMode;
			}
		}

		protected string							ModeName
		{
			get
			{
				if (this.Enabled)
				{
					if (this.is_pressed && this.is_hot)
					{
						switch (this.CheckState)
						{
							case System.Windows.Forms.CheckState.Checked:
								return "CHECKEDPRESSED";
							case System.Windows.Forms.CheckState.Unchecked:
								return "UNCHECKEDPRESSED";
							default:
								return "MIXEDPRESSED";
						}
					}
					else if (this.is_hot || this.is_pressed)
					{
						switch (this.CheckState)
						{
							case System.Windows.Forms.CheckState.Checked:
								return "CHECKEDHOT";
							case System.Windows.Forms.CheckState.Unchecked:
								return "UNCHECKEDHOT";
							default:
								return "MIXEDHOT";
						}
					}
					else
					{
						switch (this.CheckState)
						{
							case System.Windows.Forms.CheckState.Checked:
								return "CHECKEDNORMAL";
							case System.Windows.Forms.CheckState.Unchecked:
								return "UNCHECKEDNORMAL";
							default:
								return "MIXEDNORMAL";
						}
					}
				}
				else
				{
					switch (this.CheckState)
					{
						case System.Windows.Forms.CheckState.Checked:
							return "CHECKEDDISABLED";
						case System.Windows.Forms.CheckState.Unchecked:
							return "UNCHECKEDDISABLED";
						default:
							return "MIXEDDISABLED";
					}
				}
			}
		}
		
		public System.Drawing.Color					TextColor
		{
			get
			{
//				int r, g, b;
//
//				UxTheme theme = UxTheme.OpenTheme( this, "CHECKBOX" );
//				ThemeInfo
//
//				if (GetTextColor ("BUTTON", "CHECKBOX", this.ModeName, out r, out g, out b))
//				{
//					return System.Drawing.Color.FromArgb (r, g, b);
//				}
			
				return System.Drawing.Color.Black;
			}
		}
		
		protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
		{
			if (this.UseTheme)
			{
				int ox = (int) e.Graphics.VisibleClipBounds.Left;
				int oy = (int) e.Graphics.VisibleClipBounds.Top;
				int dx = (int) e.Graphics.VisibleClipBounds.Width;
				int dy = (int) e.Graphics.VisibleClipBounds.Height;
				
				if (((ox != 0) || (oy != 0) || (dx != this.Width) || (dy != this.Height)) &&
					(this.PaintChildrenBackground (e.Graphics, this, new System.Drawing.Rectangle (ox, oy, dx, dy))))
				{
				}
				else
				{
					this.ThemedPaintBackground (e.Graphics, 0, 0, this.Width, this.Height);
				}
			}
			else
			{
				base.OnPaint (e);
			}
		}

		protected override void OnTextChanged(System.EventArgs e)
		{
			base.OnTextChanged (e);
			this.string_width = -1;
		}

		protected override void OnFontChanged(System.EventArgs e)
		{
			base.OnFontChanged (e);
			this.string_width = -1;
		}
		
		protected override void OnMouseDown(System.Windows.Forms.MouseEventArgs e)
		{
			base.OnMouseDown (e);
			this.is_pressed = true;
			this.Invalidate ();
		}

		protected override void OnMouseUp(System.Windows.Forms.MouseEventArgs e)
		{
			base.OnMouseUp (e);
			this.is_pressed = false;
			this.Invalidate ();
		}

		protected override void OnMouseMove(System.Windows.Forms.MouseEventArgs e)
		{
			base.OnMouseMove (e);
			
			int x = e.X;
			int y = e.Y;
			
			bool hot;
			
			if ((x >= 0) && (x < this.Width) && (y >= 0) && (y < this.Height))
			{
				hot = true;
			}
			else
			{
				hot = false;
			}
			
			if (this.is_hot != hot)
			{
				this.is_hot = hot;
				this.Invalidate ();
			}
		}
		
		protected override void OnMouseEnter(System.EventArgs e)
		{
			base.OnMouseEnter (e);
			this.is_hot = true;
			this.Invalidate ();
		}

		protected override void OnMouseLeave(System.EventArgs e)
		{
			base.OnMouseLeave (e);
			this.is_hot = false;
			this.Invalidate ();
		}
		
		private bool PaintChildrenBackground(System.Drawing.Graphics graphics, System.Windows.Forms.Control control, System.Drawing.Rectangle rect)
		{
			foreach (System.Windows.Forms.Control child in control.Controls)
			{
				System.Drawing.Rectangle find = new System.Drawing.Rectangle (child.Location, child.Size);
						
				if (find.Contains (rect))
				{
					System.Drawing.Rectangle child_rect = rect;
					child_rect.Offset (- child.Left, - child.Top);
					if (this.PaintChildrenBackground (graphics, child, child_rect))
					{
						return true;
					}
					
					this.ThemedPaintBackground (graphics, child.Left, child.Top, child.Width, child.Height);
					return true;
				}
			}
			
			return false;
		}
		
		private void ThemedPaintBackground(System.Drawing.Graphics graphics, int ox, int oy, int dx, int dy)
		{
			int h = this.Font.Height;
			int w = this.GetCaptionWidth (graphics);
			
			//System.IntPtr hdc = graphics.GetHdc ();
			
			try
			{
				Rectangle rect = new Rectangle( ox, oy, dx, dy );
				UxTheme.DrawThemeParentBackground( this, graphics, rect );
				ThemePart p = m_WindowTheme.Parts["CHECKBOX"];
				ThemePartState s = p.States[ModeName];

				Rectangle rect1 = new Rectangle( 0, 0, 14, this.Height );
				s.DrawBackground( graphics, rect1, rect );
//				OPaC.uxTheme.Wrapper.DrawThemeParentBackground (this.Handle, hdc, ox, oy, dx, dy);
//				OPaC.uxTheme.Wrapper.DrawBackground ("BUTTON", "CHECKBOX", this.ModeName, hdc, 0, 0, 14, this.Height, ox, oy, dx, dy);
			}
			catch
			{
			}
//			finally
//			{
//				//graphics.ReleaseHdc (hdc);
//			}
			
			graphics.DrawString (this.Text, this.Font, new System.Drawing.SolidBrush (this.TextColor), 14.0f, 0.0f);
			if (this.Focused)
			{
				System.Drawing.Rectangle rectangle = new System.Drawing.Rectangle (15, 0, w, h+2);
				System.Windows.Forms.ControlPaint.DrawFocusRectangle (graphics, rectangle);
			}
		}
		
		private int GetCaptionWidth(System.Drawing.Graphics graphics)
		{
			if (this.string_width == -1)
			{
				this.string_width = OPaC.Themed.Forms.HelperTools.MeasureDisplayStringWidth (graphics, this.Text, this.Font);
			}
			
			return this.string_width;
		}
		
		private int	string_width = -1;
		private bool is_hot = false;
		private bool is_pressed = false;
	}
}