MSMQ on Pocket PC 2003

Introduction

A few years ago mainstream software development was all about desktopsand servers, both being Personal Computers. This is rapidly changing as moreand more devices emerge. Today's world has Smartphones, Pocket PCs, TabletPCs, Media Centers and many more to emerge. As complex as it is tounderstand all these devices and their differences, Microsoft has made itequally complexit to understand the different Windows brands � Windows Embedded,Windows CE, Windows Mobile, etc. A few years ago it seemed to be cool andbleeding edge to support different devices other then the mainstream PC. Butas more devices emerge and as it becomes easier to develop software forthose devices, the more rapidly consumers and corporations will adopt them.Afew years from now it will be essential to support such devices and fordevelopers to have experience with development on such devices. This articlebuilds on top of the existing article "MSMQ, your reliable asynchronousmessage processing". It will show how MSMQ can be used on Pocket PC 2003 andat the same time provide an introduction to mobile development and theCompact Framework (CF).

Understanding the different Windows brands

Microsoft uses three main Windows brands. Each brand is targeted towards adifferent set of devices. There are gray areas between the different brands,but the device to support will determine which Windows version to use:

• WindowsEmbedded � This encompasses all versions of Windows targeted towardsany device other then the PC (desktop and server). Windows Embeddedconsists of two main brands � Windows XP Embedded and Windows CE.
• WindowsXP Embedded � This is a componentized version of Windows XPProfessional. Thus you select from the existing Windows XP Professionalcomponents which ones you want to include in your OS image. This allows youtocreate smaller OS images for different devices while still supporting anyWindows-based application (as long as the components the applicationrequires are included in the OS image). Windows XP Embedded only supportsIntel x86 hardware and is not a real time OS. Examples would be kiosks,retail devices, ATM's, etc.
• Windows CE � Is a real time operating system which also supportsplatforms other than Intel x86. It is not bound to a specific device butrather contains components to support a wide variety of small devices.
• WindowsMobile � Microsoft created Windows Mobile to provide a richexperience for end users as well as to provide strict guidelines for PocketPCsand Smartphones. Windows Mobile only runs on devices which support theWindows Mobile standard. The three main types of devices supported are:
  • PocketPC � Windows-based PDAs which support WiFi and Bluetooth andprovide mobile Word, mobile Excel, mobile Outlook and more.
  • Smartphones� Mobile phones which also support emailing, text messaging, web browsingand instant messaging.
  • PocketPC phone editions � For devices which combine PDA-type features withyour mobile phone. This supports all features of Pocket PC andSmartphone.

The diagram below visualizes the three brands. This is not a completediagram but rather concentrates on the Windows CE and Windows Mobile brands.It also shows the development tools available to build applications on theseplatforms. This MSDN article answers a number of questions about how to developfor these devices and platforms.

Microsoft also ships a Compact Framework used to build .NET applications forWindows CE and Windows Mobile (both Windows Pocket PC and WindowsSmartphone).

Building your Pocket PC 2003 application

When you create a new project you can select the project type (list on theleft side). Under Visual Basic and under Visual C# you see an entry called"Smart Device". Underneath it you find Pocket PC 2003, Smartphone 2003 andWindows CE. These are the three different devices you can use the CompactFramework on and which VS.NET 2005 allows you to create applications for.Youcan create for each an application (Windows forms), class library or controllibrary (not supported for Smartphones). This by default references theCompact Framework. Under the references you suddenly also see an "mscorlib",which is the "mscorlib" for the Compact Framework. When you add newreferences you see also that the list is smaller. That is because theCompact Framework only supports a subset of the full framework. The CompactFramework 2.0 added the System.Messaging assembly/namespace which providesfull support for MSMQ on Pocket PC and Windows CE but not for Smartphones.

Windows forms is available for all three devices and differs from thetraditional desktop Windows forms in that the screen size available is muchsmaller. The designer shows a fixed-size window which reflects the sizeavailable on selected devices. How to add controls through the toolbox, howto position and resize it, how to set its properties and how to add eventhandlers is the same as for the traditional desktop Windows forms. The listof properties and events will be shorter as not all are supported by theCompact Framework, or more specifically by the devices themselves.

When running the application the VS.NET IDE shows a deployment dialog. Youcan choose where to deploy and run the application. VS.NET providesEmulators so you can run and test the applications without requiring anactual physical device. Emulators are available for Pocket PC 2003,Smartphone 2003 and Windows CE 5.0. You can also choose a form factor,meaning the skin used when showing the device in the emulator. For exampleyou can choose between a "Pocket PC 2003 Portrait" and a "Pocket PC Phone2003 Portrait".

Running on a Pocket PC 2003 Emulator

Choose "Pocket PC 2003 SE Emulator" to deploy and run your application onthe Pocket PC Emulator. This starts a virtual machine and loads the PocketPC 2003 OS into that virtual machine. Devices like Pocket PCs andSmartphones can utilize an Intel x86 processor or an ARM (Advanced RISC Machines) processor. The emulators which come with VS.NET are emulating ARM-baseddevices. All device emulator images are stored in the following location -"C:\Program Files\MicrosoftVisual Studio 8\SmartDevices\Emulators\Images".You find the Pocket PC image under the sub folder "PocketPC\2003\1033" andthe Smartphone image under the sub folder "Smartphone\2003\1033". Keep inmind that because emulators are emulating a Pocket PC or Smartphone it willalways be slower then an actual device itself.

The emulator window shows a Pocket PC booting up, like a r
eal Pocket PC. Itthen asks in the emulator window if the Pocket PC is connected to theInternet or Work – choose "The Internet". Since this is the first time theemulator is started and no Compact Framework is yet loaded, VS.NET firstdeploys the Compact Framework onto the emulator. After that VS.NET showsagain the dialog to choose where to deploy the application (it is unclear tome why this is required, but if you always deploy to the same device oremulator you can unselect the option "Show me this dialog each time I deploythe application"). Now VS.NET starts deploying your application files ontothe Pocket PC emulator. When completed VS.NET will start the application onthe Pocket PC while remotely connecting to it so you can debug theapplication remotely. In our example it will show an exception as soon as aSystem.Messaging type gets loaded and called. This is the case because MSMQis not yet installed and configured on your Pocket PC emulator.

Loading and installing MSMQ on the Pocket PC emulator

You can tell the VS.NET IDE to upload not just the project files but alsoany other files you need to get onto the Emulator. The MSMQ redistributablefiles can be found at the following location – "C:\Program Files\MicrosoftVisual Studio 8\SmartDevices\SDK\SDKRedist\MSMQ".Because the emulator is ARM-based we take them from the ARM sub folder. Addall six files to the project and set "Build Action" in the file properties(in VS.NET) to "Content". All files marked as content will be deployed inthe same folder as your project. To change the location where yourapplication gets deployed to, bring up the Project properties (in VS 2005double click on the item Properties). Go to the "Device" tab and change the"Output file folder". This by default always points to "\Program Files"followed by your project name. Also any files you marked with "Content" inthe build action are deployed into this folder. To deploy your applicationagain, run it again, or choose "Build | Deploy Solution". After redeployingthe application, go to the Pocket PC emulator window so we can setup MSMQ onit.

The basics of using the Pocket PC Emulator

The Emulator shows you Pocket PC as it would be on any real Pocket PCdevice. In the upper left corner you see the "Windows start button". Clickon the start button and it will show the start menu. Select "Programs" tobring up the installed programs, one of them being the "File Explorer". Openthe "File Explorer" by double clicking on it which shows by default the "MyDocuments" folder. Click on the white space at the bottom of the fileexplorer and keep the mouse pressed till the popup menu shows. Select fromthe menu "View All Files" so we see all files. Right under the Windows startbutton in the upper left corner it shows "My Documents" with a down arrow.This is your current location and clicking on the down arrow brings up amenu. Click on it and select "My Device" to jump to the root folder of yourdevice. Next double click on "Program Files". This shows the "Program Files"folder where you see a "NET CF 2.0" folder where VS.NET deployed the CompactFramework as well as an "MSMQ Pocket PC" folder where our application hasbeen deployed. Now we want to copy the MSMQ redistributable files to theWindows folder. Go to the "MSMQ Pocket PC folder" and select the followingsix files (by holding down the CTRL key and clicking on each file) � visadm,msmqrt, msmqd, msmqadmext, mqoa and msmqadm. Click on one of the selectedfiles and hold down the mouse till the popup menu shows, then select "Copy".Next click again on the arrow beside the current folder location (rightunder the Windows start button) and select "My Device" from the menu. Thisshows again the root folder of the device. Double click on the "Windows"folder, press the END key to jump to the end of the file list, click on anempty space and hold the mouse key down till the menu appears and select"Paste". Now all six files have been copied to the Windows folder.

Next we configure MSMQ on this Pocket PC. This requires changing the defaultPocket PC name. Click on the Windows start button and select "Settings" fromthe start menu. Select the "System" tab at the bottom and then double clickon the "About" icon in the list. This shows the Windows "about" screen.Selectthe tab "Device ID" at the bottom which shows the current Device name as"Pocket_PC". Change the name to something like "EnterpriseMinds" and clickthe Ok button in the upper right corner. This brings you back to theSettings screen which you can close with the "X" in the upper right corner.This brings you back to the File Explorer which still shows the files wecopied into the Windows folder. Double click on "visadm" to bring up thevisual MSMQ administrator console. Click on the "Shortcuts" button andselect "Install" from the menu. Click again on the "Shortcuts" button andselect "Register" this time. Next we need to restart the Pocket PC for thechanges to take effect. Click on the "Exit" button to close "visadm" andnext on the Emulator window itself click on the "Power button" (upper rightcorner). This will ask you if you are sure and you say yes which shuts downthe device, shows a black screen and then boots it up again (this may take awhile). Now we have reset the device and we want to check if MSMQ has beenset up properly. Go back to the File Explorer, which now also appears in thestart menu and by default jumps back into the Windows folder. Start "visadm"again, click on the "Shortcut" button and select "Verify". This shows thatMSMQ has been properly installed. Now we can go back and run our sampleapplication. First close "visadm" with the "X" in the upper right corner, aswell as the File Explorer. Run again the sample application from your VS.NETIDE, which will redeploy any changed files, then launch our sampleapplication while still being connected to it remotely so you can debugthrough the VS.NET IDE.

Changes to the MSMQ Pocket PC sample application

This sample application is based on the original desktop applicationattached to the article "MSMQ, your reliable asynchronous messageprocessing". There are five main differences in the MessageQueueManagertype:

• GetMessageQueueProperties() � The MessageQueue type does notsupport the following four properties � Authenticate, Category,EncryptionRequired and MulticastAddress. These four properties have beenremoved.
• GetMessageDetails() � The Message type does not support thefollowing ten properties � AttachSenderId, Authenticated,AuthenticationProviderName, AuthenticationProviderType, ConnectorType,EncryptionAlgorithm, LookupId, TransactionStatusQueue, UseAuthentication andUseEncryption. These ten properties have been removed.
• StartTransaction() � The type MessageQueueTransaction is notsupported at all. Only single message transactions are supported. So wecompletely removed this method. 
• SendMessage() � Insteadof using a MessageQueueTransaction type we use theMessageQueueTransactionType enumeration to specify if this message is sentunder a single-message-transaction or non-transactional.
• GetListOfPrivateMessageQueues() � Used Environment.MachineNamewhich is not supported by the Compact Framework. This is set by default to"." which means local machine.