License error with ActiveX control added at run-time


If you create an application that uses an ActiveX control that you add at run-time with syntax similar to the following:

Then you build this application into an executable file, create a distribution with the Setup Wizard or InstallShield Express for Visual FoxPro Edition, and install your application on other computers, when you attempt to run code similar to the preceding code you receive an error like the following:

   Program Error
OLE error code 0x80040112: Appropriate license for this class not found.


A distribution created with the Visual FoxPro Setup Wizard or InstallShield Express only allows a run-time license, while the AddObject method requires a design time license.


Add the control you want to use into a class that is saved in a Visual Class library or into a class created with the DEFINE CLASS command. Next, add an instance of the class at run-time instead of adding the control. Please see the "More Information" section for details.

In Visual FoxPro 7.0 and later see the “AddObject” Help file topic for a workaround in those products.

More Information

Steps to reproduce the behavior

The following example demonstrates using the DEFINE CLASS command to create a subclassed OleControl, then adds the subclassed OleControl at run-time.
  1. Paste the following code into a program (.prg) file:
          PUBLIC oform1

    DEFINE CLASS form1 AS form
    AutoCenter = .T.
    cNextKey = "1_"
    Name = "Form1"
    Caption = "Treeview Demo Form"

    ADD OBJECT cmdExit AS commandbutton WITH ;
    Top = 204, ;
    Left = 276, ;
    Height = 27, ;
    Width = 84, ;
    Caption = "E\<xit"

    ADD OBJECT cmdAddLV AS commandbutton WITH ;
    Top = 204, ;
    Left = 10, ;
    Height = 27, ;
    Width = 106, ;
    Caption = "Add Listview"

    ADD OBJECT cmdAddLVClass AS commandbutton WITH ;
    Top = 204, ;
    Left = 130, ;
    Height = 27, ;
    Width = 136, ;
    Caption = "Add Listview Subclass"

    PROCEDURE Destroy

    PROCEDURE cmdExit.Click

    PROCEDURE cmdAddLV.Click

    * The following AddObject causes the error.


    PROCEDURE cmdAddLVClass.Click
    * The following code shows the workaround. The class OC1 is
    * defined in the last 3 lines of this program.
    * Alternanely, you could use an object stored in a Visual Class
    * library (.vcx) file.



    thisform.setall('enabled', .F.,'commandbutton')
    WITH thisform.LV1
    .visible = .t.
    .height = 190
    .left = 75
    .width = 250
    .view = 2
    .listitems.add(,,"List Item 1",,)
    .listitems.add(,,"List Item 2",,)
    thisform.cmdExit.enabled = .t.

    DEFINE class OC1 as olecontrol
    OleClass = 'mscomctllib.listviewctrl.2'
  2. Add the program to a project and build the project into an executable (.exe) file. Name the file lvtest.exe.
  3. Create a directory called TestDir and place a copy of the executable file from the preceding Step 2 into the directory.
  4. Run the Visual FoxPro Setup Wizard.
  5. In the Setup Wizard dialog box, "Step 1 Locate Files" is displayed in the list box. In the Distribution Files text box select the TestDir directory you created in Step 3, click Select and then click Next.
  6. In the Setup Wizard dialog box, "Step 2 Specify Components" is displayed in the text box. In the Application Components option group, select the "Visual FoxPro runtime" check box.
  7. Next, select the ActiveX controls check box. The Add ActiveX Controls dialog box appears.
  8. Scroll through the "Select ActiveX controls to install" list box, select "Microsoft ListView Control, version 6.0", click the Close button to exit the dialog box and then click Next.
  9. In the "Step 3 Create Disk Image Directory" step of the Setup Wizard, select or type in the directory name you want to use for the creation of your disk images, and then click Next.
  10. In "Step 4 Specify Setup Options", of the Setup Wizard dialog box, type "ListView Test App" in the "Setup dialog box caption" text box and type "None" in the Copyright information text box and then click Next.

    NOTE: In each case, type in the text without the quotation marks.
  11. In the "Step 5 Specify Default Destination" step of the Setup Wizard dialog box, click Next.
  12. In the "Step 6 Change File Settings" text box, in the Setup Wizard dialog box, select the PM Item check box in the grid next to Lvtest.exe (the executable file name).
  13. In the "Program Group Menu Item" dialog box, type "ListView Test App" in the Description text box, and "%s\lvtest.exe" in the Command Line text box.

    Note Omit the quotation marks.

    Click OK to close the Program Group Menu Item Dialog box, click Next and then click Finish to complete running the Setup Wizard.
  14. In the "Setup Wizard Disk Statistics" dialog box, click Done.
  15. The distribution files will be in a subdirectory of the directory you listed in "Step 3 - Create Disk Image Directory". The subdirectory is named disk144. You can install the distribution you have created by copying the contents of the Disk1, Disk2, Disk3 and Disk4 directories to diskettes and then run the Setup.exe program from the first diskette. You can also connect to the computer that contains the distribution through a network to run the setup. The installation should be on a computer that does not already have Visual FoxPro 6.0 or Visual Studio 6.0 installed.
  16. On the installation computer, from the Windows Taskbar, select Start, point to Programs, and then point to Visual FoxPro Applications. Click the ListView Test App program item.
  17. When the application starts, click the Add Listview button. An error that is similar to the one that is listed in the "Symptoms" section occurs.
  18. Select Cancel, and repeat Step 16. This time, click the Add Listview Subclass button, and the error does not occur.
The preceding example uses a subclass of the OleControl class called OC1. This subclass is programmatically created with the DEFINE CLASS command contained in the last three lines of code in the program example.

Alternately, you could create a subclass of the OleControl class with the Visual Class Designer. Here are the steps to accomplish this task:

  1. Type the following in the Command window:
          CREATE CLASS
  2. In the New Class dialog box, type a class name. You could use OC1 to be consistent with the preceding example.
  3. Select OleControl in the Based On list box.
  4. In the Store In text box, type the name of a .vcx file in which to store the class, or select an existing .vcx file after pressing the ellipse [...] button. Use OCTest for the purposes of this example.
  5. Click the OK button to create the class.
  6. In the Insert Object dialog box, select the Create Control option button. From the Object Type list, select the ActiveX control you want to use. In order to be consistent with the preceding example, select the "Microsoft ListView Control, version 6.0" and then click OK. The new class displays in the Class Designer. You may now save the class.
  7. The following code would add an instance of the object at run-time in the preceding example:
          Thisform.NewObject('LV1','OC1', 'OCTest.vcx')
You need to be sure that the .vcx file was added to your project before building your .exe so that the NewObject command works correctly.

Id. de artículo: 192693 - Última revisión: 06/20/2008 - Revisión: 1