mainform.cs

Windows Mobile用户签名程序

/*
	MainForm class
	--
	Application's main window. Contains four sections:

	1) Collects signature in custom control.
	2) Displays signature info (segments and coordinates).
	3) Action buttons.
	4) Status bar at bottom.
	
	User draw signature in custom control and presses the Send button
	to send the signature to the server over TCP sockets. The signature
	is flattened to a stream of bytes and encrypted using the crypto APIs.
*/

using System;
using System.Drawing;
using System.Windows.Forms;
using System.Text;
using Common;


namespace PocketSignature
{
	/// <summary>
	/// Main form.
	/// </summary>
	public class MainForm : System.Windows.Forms.Form
	{
		// socket communications
		ClientSocket _client = new ClientSocket();
		
		// custom signature control
		SignatureControl _signature = new SignatureControl();

		// handle updates from socket
		EventHandler _processCommand;

		// hold socket notification arguments
		NotifyCommand _notifyCommand;
		object _notifyData;

		private System.Windows.Forms.Panel areaSignature;
		private System.Windows.Forms.Button butNew;
		private System.Windows.Forms.Button butConnect;
		private System.Windows.Forms.Button butSend;
		private System.Windows.Forms.TextBox textDetails;
		private System.Windows.Forms.StatusBar statusBar;
		private System.Windows.Forms.Button butOptions;

		public MainForm()
		{
			//
			// Required for Windows Form Designer support
			//
			InitializeComponent();

			// add signature control to form
			_signature.Location = areaSignature.Location;
			_signature.Size = areaSignature.Size;
			this.Controls.Add(_signature);
		}
		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			base.Dispose( disposing );
		}
		#region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			System.Resources.ResourceManager resources = new System.Resources.ResourceManager(typeof(MainForm));
			this.statusBar = new System.Windows.Forms.StatusBar();
			this.butConnect = new System.Windows.Forms.Button();
			this.butSend = new System.Windows.Forms.Button();
			this.areaSignature = new System.Windows.Forms.Panel();
			this.butOptions = new System.Windows.Forms.Button();
			this.butNew = new System.Windows.Forms.Button();
			this.textDetails = new System.Windows.Forms.TextBox();
			// 
			// statusBar
			// 
			this.statusBar.Location = new System.Drawing.Point(0, 272);
			this.statusBar.Size = new System.Drawing.Size(240, 24);
			this.statusBar.Text = "Offline";
			// 
			// butConnect
			// 
			this.butConnect.Font = new System.Drawing.Font("Tahoma", 8F, System.Drawing.FontStyle.Regular);
			this.butConnect.Location = new System.Drawing.Point(120, 248);
			this.butConnect.Size = new System.Drawing.Size(54, 20);
			this.butConnect.Text = "Connect";
			this.butConnect.Click += new System.EventHandler(this.butConnect_Click);
			// 
			// butSend
			// 
			this.butSend.Font = new System.Drawing.Font("Tahoma", 8F, System.Drawing.FontStyle.Regular);
			this.butSend.Location = new System.Drawing.Point(64, 248);
			this.butSend.Size = new System.Drawing.Size(54, 20);
			this.butSend.Text = "Send";
			this.butSend.Click += new System.EventHandler(this.butSend_Click);
			// 
			// areaSignature
			// 
			this.areaSignature.BackColor = System.Drawing.Color.Gainsboro;
			this.areaSignature.Location = new System.Drawing.Point(8, 8);
			this.areaSignature.Size = new System.Drawing.Size(224, 120);
			this.areaSignature.Visible = false;
			// 
			// butOptions
			// 
			this.butOptions.Font = new System.Drawing.Font("Tahoma", 8F, System.Drawing.FontStyle.Regular);
			this.butOptions.Location = new System.Drawing.Point(176, 248);
			this.butOptions.Size = new System.Drawing.Size(54, 20);
			this.butOptions.Text = "Options";
			this.butOptions.Click += new System.EventHandler(this.butOptions_Click);
			// 
			// butNew
			// 
			this.butNew.Font = new System.Drawing.Font("Tahoma", 8F, System.Drawing.FontStyle.Regular);
			this.butNew.Location = new System.Drawing.Point(8, 248);
			this.butNew.Size = new System.Drawing.Size(54, 20);
			this.butNew.Text = "New";
			this.butNew.Click += new System.EventHandler(this.butNew_Click);
			// 
			// textDetails
			// 
			this.textDetails.BackColor = System.Drawing.SystemColors.Info;
			this.textDetails.Location = new System.Drawing.Point(8, 136);
			this.textDetails.Multiline = true;
			this.textDetails.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;
			this.textDetails.Size = new System.Drawing.Size(224, 104);
			this.textDetails.Text = "";
			// 
			// MainForm
			// 
			this.ClientSize = new System.Drawing.Size(240, 296);
			this.Controls.Add(this.textDetails);
			this.Controls.Add(this.areaSignature);
			this.Controls.Add(this.butConnect);
			this.Controls.Add(this.butSend);
			this.Controls.Add(this.statusBar);
			this.Controls.Add(this.butOptions);
			this.Controls.Add(this.butNew);
			this.Icon = ((System.Drawing.Icon)(resources.GetObject("$this.Icon")));
			this.MinimizeBox = false;
			this.Text = "Pocket Signature";
			this.Closing += new System.ComponentModel.CancelEventHandler(this.MainForm_Closing);
			this.Load += new System.EventHandler(this.MainForm_Load);

		}
		#endregion

		/// <summary>
		/// The main entry point for the application.
		/// </summary>

		static void Main() 
		{
			Application.Run(new MainForm());
		}

		//
		// events
		//

		private void MainForm_Load(object sender, System.EventArgs e)
		{
			// prompt user if have not set the server ip address
			if (Global.Settings.GetString(SettingKeys.IpAddress) ==
				Global.Const.EmptyAddress)
			{
				if (MessageBox.Show(
					"Would you like to set the server IP address now?",
					this.Text, MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1) ==
					DialogResult.Yes)
				{
					ShowOptionsForm();
				}
			}
			
			// setup callbacks
			_signature.SignatureUpdate += new EventHandler(SignatureUpdate);
			_client.Notify += new ClientSocket.NotifyEventHandler(NotifyCallback);
			_processCommand = new EventHandler(ProcessSocketCommand);
			
			// enable command buttons
			UpdateButtons();
			
			// connect to server when first startup
			ConnectToServer();
		}

		private void MainForm_Closing(object sender, System.ComponentModel.CancelEventArgs e)
		{
			// disconnect from server when app closes
			DisconnectFromServer();
		}

		private void butConnect_Click(object sender, System.EventArgs e)
		{
			ConnectToServer();
		}
		
		private void butNew_Click(object sender, System.EventArgs e)
		{
			// clear current signature
			_signature.Clear();
			textDetails.Text = "";
		}

		private void butSend_Click(object sender, System.EventArgs e)
		{
			try
			{
				statusBar.Text = "Sending signature...";

				// encrypt the signature data
				byte[] encryptData = Crypto.Encrypt(
					Global.Settings.GetString(SettingKeys.CryptPassphrase),
					_signature.SignatureBits);

				UpdateSignatureDetails();
					
				// send to server
				_client.Send(encryptData);
			}
			catch (Exception ex)
			{
				statusBar.Text = "Error";
				textDetails.Text = ex.Message;
			}
		}

		private void butOptions_Click(object sender, System.EventArgs e)
		{
			// display the options form
			ShowOptionsForm();
		}

		// notification from signature control
		private void SignatureUpdate(object sender, EventArgs args)
		{
			// a new segment was added to the signature
			UpdateSignatureDetails();
		}
		
		// notification from socket
		private void NotifyCallback(NotifyCommand command, object data)
		{
			try
			{
				// The .Net Compact Framework does not support Control.Invoke
				// that allows you to pass arguments to the delegate. So save
				// arguments to class fields and then invoke the delegate.
				lock(this)
				{
					// save arguments to class fields				
					_notifyCommand = command;
					_notifyData = data;
					
					// execute the method on the GUI's thread, this method
					// uses the _notifyCommand and _notifyData fields
					Invoke(_processCommand);
				}
			}
			catch
			{
			}
		}

		
		// 
		// helper methods
		//
		
		private void UpdateSignatureDetails()
		{
			// display info on line segments
			StringBuilder sb = new StringBuilder();
			sb.AppendFormat(null, "Signature details\r\nNumber of segments : {0}", _signature.Lines.Count);
			
			// loop through all line segments
			for (int i=0; i < _signature.Lines.Count; i++)
			{
				// get points for this line segment
				Point[] points = (Point[])_signature.Lines[i];
				sb.AppendFormat(null, "\r\n\r\nSegment {0} ({1} points)\r\n", i+1, points.Length);
				foreach (Point pt in points)
				{
					sb.AppendFormat(null, "({0},{1}) ", pt.X, pt.Y);
				}
			}

			textDetails.Text = sb.ToString();
		}


		private void ConnectToServer()
		{
			// only connect if user has set the server IP address
			if (Global.Settings.GetString(SettingKeys.IpAddress) == Global.Const.EmptyAddress)
			{						
				textDetails.Text = "Need to set the server IP address.";
				return;
			}
			
			statusBar.Text = "Connecting to server...";

			_client.Connect(
				Global.Settings.GetString(SettingKeys.IpAddress),
				Global.Settings.GetInt(SettingKeys.PortNumber));
		}
		
		private void DisconnectFromServer()
		{
			statusBar.Text = "Offline";
			_client.Disconnect();
		}
		
		private void ShowOptionsForm()
		{
			OptionsForm form = new OptionsForm();
			form.ShowDialog();
		}

		// process socket notification, executes on GUI's thread
		private void ProcessSocketCommand(object sender, EventArgs args)
		{
			string status = "";
			switch (_notifyCommand)
			{
				case NotifyCommand.Connected:
					bool connected = (bool)_notifyData;
					status = connected ? 
						"Connected to server" : 
						"Offline"; 
					break;
					
				case NotifyCommand.SentData:
					status = "Sent signature";
					_client.Receive();
					break;

				case NotifyCommand.ReceivedData:
					bool success = (bool)_notifyData;
					status = success ? 
						"Server received signature" :
						"Server did not receive signature";
					break;
					
				case NotifyCommand.Error:
					textDetails.Text = "Socket error\r\n" + (string)_notifyData;
					DisconnectFromServer();
					break;
			}
			
			// enable action buttons
			UpdateButtons();
			
			// update the status bar
			statusBar.Text = status;
		}

		// enable actions buttons				
		private void UpdateButtons()
		{
			butSend.Enabled = _client.Connected;
			butConnect.Enabled = !butSend.Enabled;
		}
	}
}