PRB: Add Method/Add Property Adds To All Interfaces

ID: Q168528

The information in this article applies to:

Microsoft Visual C++, 32-bit Editions, versions 5.0, 6.0

SYMPTOMS

In a wizard-generated application that supports Automation, you can use the Add Method or Add Property on the popup menu in the ClassView or in the ClassWizard's Automation tab dialog box to add a method or a property to a dispinterface. The method or the property is added to all of the dispinterfaces in the project's .odl file. This is incorrect. It should only be added to one interface.

CAUSE

When a dispinterface is created by either ClassWizard or the New Class from the ClassView, the following code skeleton is added to the project's .ODL file:


  [ uuid(0C4A40A4-9B05-11D0-81EF-00AA00B92AB3) ]
  dispinterface ITesting
  {
    properties:
     // NOTE - ClassWizard will maintain property information here.
     //    Use extreme caution when editing this section.
     //{{AFX_ODL_PROP(CTestingDoc)
     //}}AFX_ODL_PROP

    methods:
     // NOTE - ClassWizard will maintain method information here.
     //    Use extreme caution when editing this section.
     //{{AFX_ODL_METHOD(CTestingDoc)
     //}}AFX_ODL_METHOD
  };

The AFX_ODL_PROP() and AFX_ODL_METHOD() in the comments are used by the ClassWizard to maintain method/property information. They also specify the object type of the dispinterface. For example, in the sample code above, the dispinterface ITesting is associated with CTestingDoc object. If you created a new dispinterface by copying and pasting an existing dispinterface without making any changes, ClassWizard would be confused if you tried to add a new method or a new property using either the ClassWizard or the popup menu's Add Method/Add Property. Hence, the property or the method is added to both interfaces.

RESOLUTION

To work around the problem, you can use any of the following methods:

Use ClassWizard to add a class as follows:
1. Launch the ClassWizard and click the Automation tab.
2. Click "Add Class..." and choose "New...".
3. In the New Class dialog box, type a class name and make sure its base class is a CCmdTarget class or its derived classes.
4. In the Automation group, select "Createable by type ID:".
5. This creates a new class and its disinterface. The interface is appended to the end of the existing .ODL file.

Use the New Class option on the popup menu in the ClassView to add a class as follows:
1. In the ClassView popup menu, click "New Class".
2. Follow steps c, d and e above to create a new class and its dispinterface.

Remove the comments you copied over from an existing dispinterface. Notice if the ClassWizard-required comments are deleted, you cannot add methods or properties to the interface using the ClassWizard or the popup menu.

STATUS

MORE INFORMATION

Steps to Reproduce Behavior

Create an AppWizard-generated application with Automation support.

Open project's .odl file and copy the existing dispinterface, including the uuid portion.

Paste the dispinterface at the end of the .odl file.

Change the uuid to a new unique number.

Go to the ClassView and right-click the wizard-generated interface. This should bring up the popup menu.

Choose Add Method to add a method to the existing interface.

Notice that the method was added to both interfaces.

Additional query words: Wizard all kbvc500 kbvc600

Keywords : kbtool kbwizard kbMFC kbVC kbVC500 kbVC600 kbGrpDSTools
Version : 5.0 6.0
Platform : NT WINDOWS
Issue type : kbprb