[Mono-bugs] [Bug 76326][Nor] Changed - Sometimes Windows Forms get a Null Reference Exception

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Changed by carlos at applianz.com.

http://bugzilla.ximian.com/show_bug.cgi?id=76326

--- shadow/76326	2005-10-04 22:10:06.000000000 -0400
+++ shadow/76326.tmp.4260	2005-10-05 15:04:25.000000000 -0400
@@ -79,6 +79,142 @@
 Sorry can't give you the code that reproduces it, work related, and
 strangely enough it only happens on one of my many .net apps I am
 trying out under mono, I will keep trying to write some code I can
 submit to reproduce the problem.
 If its any help I am pretty sure it always worked on 1.1.8 although I
 did much less testing before 1.1.9 was already out.
+
+------- Additional Comments From carlos at applianz.com  2005-10-05 15:04 -------
+I have some simple code that reproduces the problem most of the time
+on Gentoo 64bit, the code was compiled on Windows 32bit. I think it
+has to do with the using of the Listbox from a separate thread maybe
+even before the Form is ran by Application.Run
+
+using System;
+using System.Drawing;
+using System.Collections;
+using System.ComponentModel;
+using System.Windows.Forms;
+using System.Data;
+
+namespace Test
+{
+	/// <summary>
+	/// Summary description for Form1.
+	/// </summary>
+	public class Form1 : System.Windows.Forms.Form
+	{
+		private System.Windows.Forms.TextBox textBox1;
+		private System.Windows.Forms.ListBox listBox1;
+		private System.Windows.Forms.Button button1;
+		/// <summary>
+		/// Required designer variable.
+		/// </summary>
+		private System.ComponentModel.Container components = null;
+
+		public Form1()
+		{
+			//
+			// Required for Windows Form Designer support
+			//
+			InitializeComponent();
+
+			//
+			// TODO: Add any constructor code after InitializeComponent call
+			//
+		}
+
+		/// <summary>
+		/// Clean up any resources being used.
+		/// </summary>
+		protected override void Dispose( bool disposing )
+		{
+			if( disposing )
+			{
+				if (components != null) 
+				{
+					components.Dispose();
+				}
+			}
+			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()
+		{
+			this.textBox1 = new System.Windows.Forms.TextBox();
+			this.listBox1 = new System.Windows.Forms.ListBox();
+			this.button1 = new System.Windows.Forms.Button();
+			this.SuspendLayout();
+			// 
+			// textBox1
+			// 
+			this.textBox1.Location = new System.Drawing.Point(40, 40);
+			this.textBox1.Name = "textBox1";
+			this.textBox1.Size = new System.Drawing.Size(88, 20);
+			this.textBox1.TabIndex = 0;
+			this.textBox1.Text = "textBox1";
+			// 
+			// listBox1
+			// 
+			this.listBox1.Location = new System.Drawing.Point(32, 88);
+			this.listBox1.Name = "listBox1";
+			this.listBox1.Size = new System.Drawing.Size(88, 95);
+			this.listBox1.TabIndex = 1;
+			// 
+			// button1
+			// 
+			this.button1.Location = new System.Drawing.Point(184, 176);
+			this.button1.Name = "button1";
+			this.button1.Size = new System.Drawing.Size(88, 64);
+			this.button1.TabIndex = 2;
+			this.button1.Text = "button1";
+			// 
+			// Form1
+			// 
+			this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
+			this.ClientSize = new System.Drawing.Size(292, 273);
+			this.Controls.Add(this.button1);
+			this.Controls.Add(this.listBox1);
+			this.Controls.Add(this.textBox1);
+			this.Name = "Form1";
+			this.Text = "Form1";
+			this.Load += new System.EventHandler(this.Form1_Load);
+			this.ResumeLayout(false);
+
+		}
+		#endregion
+
+		/// <summary>
+		/// The main entry point for the application.
+		/// </summary>
+		[STAThread]
+		static void Main() 
+		{
+			Form1 f = new Form1();
+			System.Threading.Thread thread = new System.Threading.Thread(new
+System.Threading.ThreadStart(f.Start));
+			thread.IsBackground = true;
+			thread.Start();
+			Application.Run(f);
+		}
+
+		private void Form1_Load(object sender, System.EventArgs e)
+		{
+			
+		}
+		private void Start()
+		{
+			while(true)
+			{
+				this.listBox1.Items.Add("test");
+				System.Threading.Thread.Sleep(100);
+
+			}
+		}
+	}
+}
+