Declarative Programming Of The MVC Pattern Within The Context Of DataBinding

/*
 * Copyright (c) 2004 Marc Clifton
 * All Rights Reserved
 * 
 * License: GNU General Public License, see doc\license.txt
 * http://www.gnu.org/licenses/licenses.html#GPL
 * Owner: Marc Clifton email: webmaster@knowledgeautomation.com
 * First release published:
 * http://www.codeproject.com/cs/miscctrl/xmlGuiGenerator.asp
 * 2/25/04
*/

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Reflection;
using System.Windows.Forms;
using System.Xml;

namespace MyXaml.Extensions
{
	public class ItemInfo
	{
		protected Control style;
		protected int height;

		public Control Style
		{
			get {return style;}
		}

		public int Height
		{
			get {return height;}
			set {height=value;}
		}

		public ItemInfo(Control style, int height)
		{
			this.style=style;
			this.height=height;
		}
	}

	public class StyledListBox : ListBox
	{
		protected string visualStyle;
		protected Hashtable itemCollection;
		protected int margin;
		protected Control style;

		public string VisualStyle
		{
			get {return visualStyle;}
			set
			{
				visualStyle=value;
				style=(Control)Parser.CurrentInstance.CreateForm(visualStyle, null, null);
			}
		}

		public int Margin
		{
			get {return margin;}
			set {margin=value;}
		}

		public StyledListBox()
		{
			itemCollection=new Hashtable();
			DrawMode=DrawMode.OwnerDrawVariable;
		}

		public string SubItem(int n)
		{
			Control style=((ItemInfo)itemCollection[SelectedIndex]).Style;
			string text=GetText(style.Controls[n], SelectedIndex);
			return text;
		}

		protected override void OnSizeChanged(EventArgs e)
		{
			foreach(DictionaryEntry entry in itemCollection)
			{
				int index=(int)entry.Key;
				ItemInfo info=(ItemInfo)entry.Value;
				info.Height=GetItemHeight(info.Style, index);
				RefreshItem(index);
			}
		}

		protected override void OnMeasureItem(MeasureItemEventArgs e)
		{
			int height=0;
			if (itemCollection.Contains(e.Index))
			{
				height=((ItemInfo)itemCollection[e.Index]).Height;
			}
			else
			{
				if (visualStyle != null)
				{
					height=GetItemHeight(style, e.Index);
					itemCollection.Add(e.Index, new ItemInfo(style, height));
				}
			}
			e.ItemHeight=height+margin;
		}


		protected override void OnDrawItem(DrawItemEventArgs e)
		{
			if (e.Index != -1)
			{
				if ((e.State & DrawItemState.Selected)==0)
				{
					e.Graphics.FillRectangle(new SolidBrush(SystemColors.Window), e.Bounds);
				}
				else
				{
					Color colorStart=Color.FromArgb(255, 245, 200);
					Color colorEnd=Color.FromArgb(255, 210, 128);
					e.Graphics.FillRectangle(new LinearGradientBrush(e.Bounds, colorStart, colorEnd, 90), e.Bounds);

					// for some reason, there is a solid line going across the top of the selection!
					Rectangle r2=e.Bounds;
					r2.Height=2;
					e.Graphics.FillRectangle(new SolidBrush(colorStart), r2);
				}

				string text;
				Rectangle r=e.Bounds;
				Control style=((ItemInfo)itemCollection[e.Index]).Style;
				foreach(Control ctrl in style.Controls)
				{
					int height;
					GetText(e.Graphics, ctrl, e.Index, out text, out height);
				
					r.Height=height;
					e.Graphics.DrawString(text, ctrl.Font, new SolidBrush(ctrl.ForeColor), r);
					r.Y=r.Y+height;

				}
			}
		}

		protected int GetItemHeight(Control style, int index)
		{
			int totalHeight=0;
			Graphics gr=Graphics.FromHwnd(style.Handle);
			foreach(Control ctrl in style.Controls)
			{
				string text;
				int height;
				GetText(gr, ctrl, index, out text, out height);
				totalHeight+=height;
			}
			return totalHeight;
		}

		protected void GetText(Graphics gr, Control ctrl, int index, out string text, out int height)
		{
			text=ctrl.Text;
			height=0;
			try
			{
				bool wordWrap=false;
				wordWrap=((TextBox)ctrl).WordWrap;
				string dataSourceName=StringHelpers.LeftOf(text, ';').Trim();
				string field=StringHelpers.RightOf(text, '=').Trim();
				Parser parser=Parser.CurrentInstance;
				object ds=parser.GetReference(dataSourceName);
				DataTable dt=null;
				TypeConverter targetTypeConverter=TypeDescriptor.GetConverter(ds.GetType());
				if (targetTypeConverter.CanConvertTo(typeof(DataTable)))
				{
					dt=(DataTable)targetTypeConverter.ConvertTo(ds, typeof(DataTable));
				}
				if (dt != null)
				{
					if (index < dt.Rows.Count)
					{
						text=dt.Rows[index][field].ToString();
						SizeF sf;
						if (wordWrap)
						{
							sf=gr.MeasureString(text, ctrl.Font, Width-20);
						}
						else
						{
							sf=gr.MeasureString(text, ctrl.Font);
						}
						height=(int)sf.Height+1;
					}
					else
					{
						text=String.Empty;
					}
				}
			}
			catch(Exception e)
			{
				Trace.WriteLine(e.Message);
			}
		}

		protected string GetText(Control ctrl, int index)
		{
			string text=ctrl.Text;
			try
			{
				string dataSourceName=StringHelpers.LeftOf(text, ';').Trim();
				string field=StringHelpers.RightOf(text, '=').Trim();
				Parser parser=Parser.CurrentInstance;
				object ds=parser.GetReference(dataSourceName);
				DataTable dt=new DataTable();
				TypeConverter targetTypeConverter=TypeDescriptor.GetConverter(ds.GetType());
				Type t=dt.GetType();
				if (targetTypeConverter.CanConvertTo(t))
				{
					dt=(DataTable)targetTypeConverter.ConvertTo(ds, t);
				}
				text=(string)dt.Rows[index][field];
			}
			catch(Exception e)
			{
				Trace.WriteLine(e.Message);
			}
			return text;
		}
	}
}