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The new embedded VB 3.0 for Win CE – First Glance

  (NOTE: While this is still relevant to some Developers, DOT NET or Visual Studio . Net now comes with the enhanced embedded technologies for VB and C embedded . net and related SDK's)

At first glance the product is a very cut down version of Visual Basic, but there are more than enough tools to get the job done, just think back to your early days in VB when you did not know how to call the API or use some of the more advanced controls when you were limited using the basic controls provided on the IDE tool bar.

 Previously one needed to have Visual Basic and then purchase the SDK for ce. Now from Microsoft you can purchase the full Embedded tools which includes the Visual C++ and Visual Basic IDE, as well as emulators for hand helds and palm tops and their SDK's. This new development tool set is great if you only want to develop for CE and do not want to purchase Visual Basic. One draw back is that to use the emulators you will need to be in an NT environment. IN fact I recommend full Windows 2000 Professional with as much ram, and video as possible.

I downloaded the tools set from Microsoft as well as order the software on disk and it cost US$10

Follow this link to the Microsoft page

Microsoft® eMbedded Visual Basic 3.0

Components included.

  • Microsoft CE Comm Control 3.0
  • Microsoft CE Commandbar Control 3.0
  • Microsoft CE Commondialog Control 3.0
  • Microsoft CE File System Control 3.0
  • Microsoft CE Grid Control 3.0
  • Microsoft CE Image Control 3.0
  • Microsoft CE Imagelist Control 3.0
  • Microsoft CE Listview Control 3.0
  • Microsoft CE Picturebox Control 3.0
  • Microsoft CE TabStrip Control 3.0
  • Microsoft CE Treeview Control 3.0
  • Microsoft CE WinSock Control 3.0

 

References:

  • Microsoft CE ADO Control (ADOCE) 2.0
  • Microsoft CE Comm Control 3.0
  • Microsoft CE File system control 3.0
  • Microsoft CE Financial Functions 3.0
  • Microsoft CE WinSock Control 3.0

 

When starting a new project you have the choice of three wizards a general , a hand held and a palm size. The hand and palm size options automatically provide you with a form of the correct size to fit on your device. – Very handy.

 

There is a comprehensive help, with language reference, samples, notes on using the debugger tool as well as a section on databases on hand held devices. The following table from the help outlines some of the missing items in the cut down eVB

 

Unsupported Properties, Events, and Methods

The following table shows the properties, events, and methods that are unsupported in Microsoft® eMbedded Visual Basic 3.0.

Property

Method

Event

Container

Drag

DragDrop

DataChanged

OLEDrag

DragOver

DataField

ShowWhatsThisMethod

LinkClose

DataSource

WhatsThisMode

LinkError

DisabledPicture

 

LinkNotify  

DownPicture

 

LinkEvent

DragIcon

 

LogEvent

DragMode

 

MouseDown*

HasDC

 

MouseMove*

Icon

 

MouseUp*

LastDLLError

 

OLECompleteDrag

LinkItem

 

OLEDragDrop

LinkMode

 

OLEDragOver

LinkTimeout

 

OLEDragOver (ActiveX controls)

LinkTopic

 

OLEGiveFeedBack

MaxButton

 

OLESetData

MDIChild

 

OLEStartDrag

MinButton

 

StartLogging

MouseIcon

 

 

MousePointer

 

 

NegotiateMenus

 

 

OLEDrag

 

 

OLEDragMode

 

 

OLEDropMode

 

 

OLEDropMode

 

 

Palette

 

 

PaletteMode

 

 

Picture

 

 

PrevInstance

 

 

RightToLeft

 

 

WhatsThisButton

 

 

WhatsThisHelpID

 

 

 

* Unsupported for the TabStrip control
 

Tips, Tricks and Pit Falls in EVB. (Embedded Visual Basic)

SDK's:

When it comes time to start developing it is important to know what your target audience is. My version of EVB (both the CD and the Download) came with SDk's for the "Windows CE Palm Size 2_1", the "Windows CE for the Pocket PC" and "Windows CE HPC Pro". I assumed that the HPC Pro would be the one I needed to create some great applications for my Jornada 720c. No! it is for the Win CE2.11!

All of the provided SDK's run in Windows Ce 2.11. Some applications, but mainly for the Pocket Pc will run on later versions of the CE. For the Jornada I needed to download another SDK. This one gave me the "Windows CE HPC 2000".

Remember Windows CE 3.0 is the 2000 flavour and the latest version is 2002. So if you want to develop for the latest crop of devices you need to download the new SDKs.

Having the device you want to develop for in front of you connected to the machine is ideal, as you will quickly find if you have chosen the correct SDk to develop in.

Pit Falls of EVB:

  • Remember EVB is very much like VBScript. There are only Variants. Use option Explicit and use a systematic naming convention, such as Hungarian, so you know what your variables should contain. This should help reduce errors.
  • Very Very Limited error trapping. Use of "On error resume" is recommended! - there is no goto
  • Memory Leakage. Microsoft KB article Q286504 - "eVB CreateObject Function Causes memory Leak" I do not think Microsoft has fixed this problem yet. When you create an object, the space is allocated. However the space is not given back until the application is closed. Not even on assigning the object to "Nothing" or if the object goes out of scope.

To Compile or Not to Compile:

Projects are not compiled in eVB. This means that an interpreter and about 4 other files must be present on a device to run an eVB project. So space and a largish setup file is required. Where the upside is, is that you do not have to program specifically for a processor, as Each processor has it's own interpreter.

So all projects will appear with the standard Icon. If you want to change the Icon you will need to write an application (in C) that calls your program and launches the interpolator. The application can have any icon.

 

 

 

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