PRG 240 - Class #13 Lecture

Quiz on Ch. 6 concepts (classes)

Finish Ch. 8 Lecture & Discussion

• Component Object Model (COM)
  • ActiveX Dll
    • runs in the memory space of the consumer application; this is called in-process
  • ActiveX Exe
    • runs in its own memory space; this is called out-of-process
      
      
• Testing Components (p. 362)
  • For ActiveX Dll's (in-process), you must use the Project Group feature of VB
  • For ActiveX Exe's (out-of-process), you must open two instances of VB where the Exe project is opened with one copy of VB and the client application is opened in the other.
    
    
• Registering components
  • Each component is assigned a unique GUID (globally unique indentifier) which is kept track by the Windows Registry
  • You can use VB to register an ActiveX Dll on your computer. To register a Dll on a different computer, you can use C:\Windows\System\Regsvr32.exe with the DOS command
    
    REGSVR32 C:\MyProjectFolder\MyComponent.dll
    
    
  • ActiveX Exe components are automatically registered on a PC on which they are compiled.
    
    
• Create an ActiveX Dll
  • Follow the steps on pp. 364-370 to create and test Ch08ActiveX.dll
    
    
• Create an ActiveX Exe
  • Follow the steps on pp. 372-374 to create and test Ch08ActiveX.exe
  • Code is available to copy and paste for:
    • Ch08ActiveXExeClient
      • frmDispensary.frm
    • Ch08ActiveXExeServer
      • frmDispensaryItem.frm
      • standard code module (Module1.bas)
      • CDispensaryItem.cls
      • CDispensaryItems.cls
        
        
• (if time) As a class, do Programming Exercise 8.1 on p. 392 by creating an ActiveX Dll that computes simple annual interest.

Ch. 9 Lecture & Discussion

• Besides Dll's & Exe's, there is another type of ActiveX COM component called an ActiveX document.
  
  
• An ActiveX document must execute within a container such as an Internet Explorer browser. It can run in-process (Dll) or out-of-process (Exe). An ActiveX document within a VB project is actually a UserDocument object.
  
  
• UserDocument objects look like and share some similarities with forms. However, a UserDocument does not have Activate or Load events. Rather, a UserDocument does have events such as InitProperties, ReadProperties, and WriteProperties in addition to Initialize.
  
  
• A HyperLink object can be used in conjunction with a UserDocument to allow someone to link to a Web site. Use the NavigateTo method of a HyperLink object such as:
  
  HyperLink.NavigateTo "http://www.minich.com"
  
  
• You can use the MenuEditor to create a menu for a UserDocument although its menu must merge with the menu of its container.
  
  
• A UserDocument object is actually stored in a file with a .dob extension. When a project is compiled as a Dll or Exe, it is stored as a file with a .vbd extension.
  
  
• Preview the ActiveXUserDocuments.dll exercise from the Student CD-ROM.
  
  
• Follow the steps on pp. 398 - 409 to create your own ActiveXUserDocuments.dll
  • docOne.dob,
  • docTwo.dob
  • frmAbout.frm
  • stdCode.bas
  • Discuss the PropertyBag (PropBag).
    

Review Ch. 5 VB Auto Center specs & spend the remaining time working on that assignment.

Homework Assignment:

• Review any notes and/or activities in the above lecture that were not covered in class.
• Read Ch. 10
• Finish Ch. 5 VB Auto Center #1 only on p. 248. That is, make your Ch. 4 VB Auto Center project work with ADO object code rather than a Data Environment.