A Practical Use of the MVC Pattern

using System;
using System.ComponentModel;
using System.Data;
using System.Windows.Forms;
using MvcExample.Models;

namespace MvcExample.Views
{
	public class BaseView : Form
	{
		public event EventHandler ViewClosed;

		#region Windows Form Designer generated code
		protected System.Windows.Forms.Button butClose;
		protected System.Windows.Forms.ProgressBar progressBar;

		private Container components = null;

		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose(bool disposing)
		{
			if (disposing)
			{
				if (components != null)
				{
					components.Dispose();
				}
			}
			base.Dispose(disposing);
		}


		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			this.butClose = new System.Windows.Forms.Button();
			this.progressBar = new System.Windows.Forms.ProgressBar();
			this.SuspendLayout();
			// 
			// butClose
			// 
			this.butClose.Anchor = ((System.Windows.Forms.AnchorStyles) ((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
			this.butClose.Location = new System.Drawing.Point(200, 240);
			this.butClose.Name = "butClose";
			this.butClose.Size = new System.Drawing.Size(80, 24);
			this.butClose.TabIndex = 2;
			this.butClose.Text = "&Close";
			this.butClose.Click += new System.EventHandler(this.butClose_Click);
			// 
			// progressBar
			// 
			this.progressBar.Location = new System.Drawing.Point(8, 248);
			this.progressBar.Name = "progressBar";
			this.progressBar.Size = new System.Drawing.Size(184, 16);
			this.progressBar.TabIndex = 3;
			// 
			// BaseView
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
			this.ClientSize = new System.Drawing.Size(292, 271);
			this.Controls.Add(this.progressBar);
			this.Controls.Add(this.butClose);
			this.Name = "BaseView";
			this.Text = "BaseView";
			this.ResumeLayout(false);

		}
		#endregion

		#region constructor
		public BaseView()
		{
			InitializeComponent();
			this.Closed += new EventHandler(OnViewClosed);
		}
		#endregion constructor

		#region form eventhandlers
		private void OnViewClosed(object sender, EventArgs ea)
		{
			if (ViewClosed != null)
			{
				ViewClosed(this, ea);
			}
		}

		private void butClose_Click(object sender, EventArgs e)
		{
			this.Close();
		}
		#endregion form eventhandlers

		#region public methods 
		/// <summary>
		/// Called from the controller to update the View when the Model 
		/// is finished loading the data.
		/// </summary>
		public void UpdateView(object sender, EventArgs ea)
		{
			BaseModel model = sender as BaseModel;
			if (model == null)
				return;

			DataSet ds = model.QueryModel();
			ContinueUpdateView(ref ds);

			progressBar.Visible = false;
		}

		/// <summary>
		/// Called from the controller to update the View's progressbar when
		/// the Model is reporting some progress.
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="percent"></param>
		public void UpdateProgress(object sender, int percent)
		{
			progressBar.Visible = true;

			if (percent >= 0 && percent <= 100)
			{
				progressBar.Value = percent;
			}
			else
			{
				progressBar.Value = 0;
			}
		}
		#endregion public methods

		#region virtual methods
		/// <summary>
		/// This method could be declared as abstract (and then the whole 
		/// BaseView class as an abstract class) but then we lose the ability to edit the
		/// form in the form editor.
		/// </summary>
		/// <param name="ds"></param>
		protected virtual void ContinueUpdateView(ref DataSet ds)
		{
		}
		#endregion virtual methods
	}
}