C#

[System.Runtime.InteropServices.DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool IsIconic(IntPtr hWnd);

using System.Collections;
 
private ArrayList ProcessesWithMainWindow = new ArrayList();
private ArrayList ProcessesIconic = new ArrayList();

private void SearchRunningProcesses()
{
	Process[] allRunningProcesses= Process.GetProcesses();
	foreach(Process actProcess in allRunningProcesses)
	{
		if(actProcess.MainWindowHandle!=IntPtr.Zero)
		{
			if(!ProcessesWithMainWindow.Contains(actProcess))
			{
				ProcessesWithMainWindow.Add(actProcess);
				actProcess.EnableRaisingEvents = true;
				actProcess.Exited+=new EventHandler(actProcess_Exited);
			}
		}
		else
		{
			actProcess.Dispose();
		}
	}
}

private void ValidateProcesses()
{
	foreach(object actObject in ProcessesWithMainWindow)
	{
		Process actProcess = actObject as Process;
		if(actProcess.MainWindowHandle!=IntPtr.Zero)
		{
			if(IsIconic(actProcess.MainWindowHandle))
			{
				if(!ProcessesIconic.Contains(actProcess))
				{
					ProcessesIconic.Add(actProcess);
				}
			}
			else
			{
				if(ProcessesIconic.Contains(actProcess))
				{
					ProcessesIconic.Remove(actProcess);
					//Process was Iconic and is now on an other state
					//You can now show your messagebox here
					//actProcess.ProcessName will give you the Info
				}
			}
		}
	}
}

private void actProcess_Exited(object sender, EventArgs e)
{
	Process actProcess = sender as Process;
 
	ProcessesWithMainWindow.Remove(actProcess);
 
	if(ProcessesIconic.Contains(actProcess))
	{
		ProcessesIconic.Remove(actProcess);
	}
	actProcess.Exited-=new EventHandler(actProcess_Exited);
	actProcess.Dispose();
}

SearchRunningProcesses();
ValidateProcesses();

JoZ CaVaLLo wrote:

and is concerned about the use of SortedLists because of memory performances.

JoZ CaVaLLo wrote:

Can somebody tell me when the Garbage Collector is called to clean sorted lists that are not used anymore?

private void YourMethod()
{
    using(SortedList yourSL = new SortedList())
    {
        yourSL.Add(....
    }
    //The dispose method will automatically be called at the end of the "using"-block
    //A "using"-block can be used for all classes, which implement "IDisposable".
}

protected override void Dispose( bool disposing )
{
    if( disposing )
    {
        if(yourSL != null)
            yourSL.Dispose();
    }
    base.Dispose( disposing );
}

Martin# wrote:

But, he is only able if there are no references left, which hold the instance of the sorted List.
Therefor you have to call the Dispose() method.

Martin# wrote:

using(SortedList yourSL = new SortedList())