If you're using the sample code from Alex Feinman's MSDN article on hosting ActiveX controls, then you might be interested to know that we've found and fixed a bug in it.  The original code doesn't properly clean up and destroy the native control instances, so the native destructor is never called and you leak objects.  For many things like Media Player, where you create one control and use it for the life of your app it's not much of a problem, but if you're creating and disposing a lot of controls in your app, it is a problem.

The fixed file is available here [AxHost.zip (7.89 KB)]

Today I saw two separate posts on pretty much the same question.  How can you determine if the foreground window changes in a WinMo application?  Moreover, how can you determine if the new foreground window is your own, or in some other process?  My initial thoughts were to do some work in the Form's Deactivate event, but that would lead to having to plumb it into every Form, and then you'd still need special case handlers for MessageBoxes and Dialogs and it would be an unmaintainable pain in the ass. I decided to put some time aside this afternoon and see if I could come up with a better solution, and what I came up with is outlined in a new article entitled 'Determining Form and Process Changes in Windows CE'.

We've been getting a lot of inquiries lately about our plans for releasing the SDF built for Visual Studio 2008 and against CF 3.5, so I'll lay out our current status and short-term plan.

I realize we're a bit late in releasing a version for Studio '08.  Now you might say to yourself "how hard can it be?  Just open the solution in Studio '08, let it upgrade, recompile and release."  Sure, it could be that simple if we wer content with just tossing it out there, but we're not.  With the move to Studio '08 we decided to take advantage of some of the new tools we have.  First we migrated the entire SDF source tree from Vault to TFS.  Vault worked just fine, but we wanted to take advantage of TFS and integrate both continuous integration, automated testing and test-driven development into the product. 

That mean rearchitecting the solution and projecy layouts and then writing tests.  Lots of tests.  Of course writing tests leads to finding bugs, which then leads to fixing bugs.  We started by looking at reported bugs but also looking at some use cases and testing classes we know get the most use.  We have no delusion that we're going to have even close to full code coverage (or even 50%) by our next release, but we want to get off on the right foot and at least have some coverage for the next release.

Of course we've also added some new features like the OpenNETCF.Net.Mail namespace and all of this takes time.  As of right now we have less than 40 hours of test writing left to hit our release milestone.  Once we hit that, we then have to build the Help and installation package and release.  My hope is to have something ready in early September, but that's not a guarantee.  We know you want the release - we do - we just want to make sure it's right.

An ancillary question that also comes up is "when will we be releasing a version compiled for CF 3.5?"  As of right now we have no plans to release a CF 3.5-targeted version of the SDF.  Yes, you read that right.  We have no plan for a CF 3.5 release.  "Why is that?" you might ask, after all CF 3.5 is the latest and greatest, right?  Sure, it is, and we think that when possible you should use it.  However the SDF has historically been used by developers using older versions of the CF and is already rolled out in a *lot* of CF 2.0 projects.  If we moved to 3.5, none of those 2.0 project would be able to use the SDF without recompiling themselves.  If we moved to 3.5, then we'd also be tempted to use 3.5 features, which would then even make the source incompatible with 2.0 and a recompile wouldn't even be an option. I, for one, don't really want to leave all of those CF 2.0 developer's high and dry. 

Since CF 3.5 assemblies are unusable in CF 2.0 projects, but CF 2.0 assemblies can be used without a problem in CF 3.5 applications it makes the decision pretty simple.  If we stay with CF 2.0 as a target, then far more people can use the library.  If you absolutely must have it built targeting CF 3.5, you can always recompile the source yourself.

    Microsoft has released SQL Server Compact 3.5 SP1, providing support for the ADO.NET Entity Framework and 64-bit desktops.

It seems that every time I work on a project I get near the end and have to deal with actual deployment of the application and things go south.  Let's face it, Microsoft's wceload application sucks - and that's being generous. It's limited, it's got no object model, and it's behavior has changed over time without any of those changes being documented.

In a recent project I was trying to silently install an application to a directory that would change depending on the target hardware becasue different devices have their storage media named differently.  I wanted to do this without changing or having multiple CAB files, since the application was no different. Achieving this with wceload, I am convinced, is utterly impossible so I put on my reverse-engineering hat, downloaded the CAB spec (cabfmt.doc), and went to work.  Now, a few month later, and with the help of Alex Feinman, we've created a new product called the Windows CE CAB Installer SDK.  In addition to a new product, we went with a new pricing model as well.

The SDK comes with full source,  unit and integration tests designed for running under mstest, samples for generating compressed and uncompressed CAB (the SDK supports both), a template for creating custom installer DLLs and both VB and C# examples of using the SDK.

The main workhorse of the SDK is the WinCEInstallerFIle class, which looks like this:

An example of a custom installer looks like this (just to give you a flavor of how it works):

using System;

using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using OpenNETCF.Compression.CAB;

namespace System.Runtime.CompilerServices
{
  public class ExtensionAttribute : Attribute
  {
  }
}

namespace ONCFInstall
{
  public delegate void FileProgressHandler(int progressPercent);

  public static class Extensions
  {
    public static string Find(this List list, string findString)
    {
      foreach (string file in list)
      {
        if (string.Compare(file, findString, true) == 0)
        {
          return file;
        }
      }
      return null;
    }
  }

  public class CustomCABInstaller : WinCEInstallerFile
  {
    private int m_fileCount = 0;
    private CommandLineArgs m_args;

    public event FileProgressHandler FileProgress;

    public CustomCABInstaller(string cabFileName, CommandLineArgs args)
      : base(cabFileName)
    {
      m_args = args;
      SkipFileNames = m_args.SkipFiles ?? new List();
      PathStringReplacements = m_args.PathStringReplacements ?? new Dictionary();
      SkipOSVersionCheck = m_args.SkipOSVersionCheck;
    }

    /// 

    /// List of file names to skip during installation
    /// 
    public List SkipFileNames { get; set; }

    /// 

    /// List of path replacement strings
    /// 
    public Dictionary PathStringReplacements { get; set; }

    /// 

    /// If true, the installer will not check to ensure the target meets the installer's version requirements
    /// 
    public bool SkipOSVersionCheck { get; set; }

    public override void OnInstallBegin()
    {
      m_fileCount = 0;
    }

    public override void OnTargetOSVersionCheck()
    {
      // check to see if we should skip the OS version check
      if (!SkipOSVersionCheck)
      {
        base.OnTargetOSVersionCheck();
      }
    }

    public override void OnInstallFile(ref FileInstallInfo fileInfo, out bool skipped)
    {
      // check to see if it's a name we should skip
      if (SkipFileNames.Find(fileInfo.FileName) != null)
      {
        Utility.Output(string.Format("Skipping file '{0}'", fileInfo.FileName));
        skipped = true;
        return;
      }

      // do any path replacements
      foreach (KeyValuePair val in PathStringReplacements)
      {
        fileInfo.DestinationFolder = fileInfo.DestinationFolder.Replace(val.Key, val.Value);
      }

      Utility.Output(string.Format("Installing '{0}' to '{1}'", fileInfo.FileName, fileInfo.DestinationFolder));

      base.OnInstallFile(ref fileInfo, out skipped);

      if (FileProgress != null)
      {
        FileProgress((++m_fileCount * 100) / FileCount);
      }
    }
  }
}

Today OpenNETCF announces a new pricing model that is going to be somewhat of a social experiment.  Our latest product - the Windows CE CAB Installer SDK - is being released under a "value-based" pricing (VBP) model.  In this model we're letting the customer determine how much they pay for a product based on how much value they feel it provides them.

The general idea is that we believe that most developers are honest, understand the value of time and have varying perceptions on the value of a software package.  For example a college student writing some quick utility for her personal use might find that the product saved a little time, but that she doesn't have a whole lot of expendable cash.  To her, $10 may be a reasonable representation of the value that our product brought to the solution.  On the other hand a developer working on an enterprise solution might find that the product saved his team several days of internal development and testing.  He knows the cost of his developers' time and the opportunity cost of letting them work on other product features instead of implementing what our product does.  For him $1,000 is a reasonable value.

In both cases we agree.  Software certainly doesn't always hold the same value to everyone.  We've all purchased software that we use a lot, and we feel that it was a great deal for what we paid for it.  We've all also bought software that maybe got used once or twice and that we know wasn't worth what we paid for it. Since the only person that can reasonably determine the value of the software is the customer themself, we've decided to let them pay based on their perceived value of the software.  Instead of purchasing the product, or some quantity of the product, customers will instead purchase a quantity of $5 "value units."  The number of units they purchase is completely up to them.

So now the college student can pay $10 for the exact same software that some company might pay $1,000 or more for.  If you're unsure if the software will meet your needs you can pay a small amount to give it a try - after all there is value in the effort alone.  If you determine that it does solve a problem for you and indeed does have value, you can always come back and purchase more value units.  What about bug fixes and upgrades?  New features and fixes are added value, so simply come back and purchase the number of value units that you feel represent the feature or fix.

Sure, I suspect that there will be a few people who take advantage of the model.  People who know that it saved them days of work but decide to pay in only $5.  The hope, however, is that those people will be the exception.  Software is never complete - there are always more features to add and bugs to fix.  What drives our ability to add those features and make those fixes is cash flow. We feel that if most people pay what they truly feel is the value of the product, then it will provide us enough revenue to continue working on it, and if the model works for this product, it may well spread and be applied to some of our other products as well.